Pressed Into Mud, Preserved For Twenty Thousand Years<\/p>\n
They are not large footprints.<\/p>\n
Most of them belong to people who would not have stood out in a modern crowd \u2014 adults of average build, children running alongside them, teenagers whose stride length falls somewhere between the two.<\/p>\n
They pressed into wet mud on the shore of a lake that no longer exists, in a basin that is now one of the driest places in North America, at a moment in human prehistory that most scientists, until very recently, believed was simply too early for people to have been here at all.<\/p>\n
The footprints at White Sands are real.<\/p>\n
They are physical impressions left in ancient lakebed sediment that hardened over millennia and eventually eroded to the surface in the gypsum-rich terrain of southern New Mexico.<\/p>\n
A person who knew what to look for, walking the right part of White Sands National Park at the right time of day when low-angle light throws surface texture into sharp relief, can look down and see the actual shape of a human foot from the distant past \u2014 heel, arch, toes, the slight lateral roll of a walking stride.<\/p>\n
They were identified formally by researchers in 2009, studied for years, and then dated.<\/p>\n
When the dating results came back, they did not suggest a modest revision to the existing timeline for human presence in North America.<\/p>\n
They suggested a rewrite.<\/p>\n
The footprints were approximately 21,000 to 23,000 years old.<\/p>\n
If that number is correct \u2014 and subsequent independent research has provided substantial support for the general age range, while the specific figures continue to be refined \u2014 then people were walking beside Lake Otero in what is now New Mexico during the Last Glacial Maximum, the coldest and most glaciated phase of the most recent Ice Age.<\/p>\n
They were here when the Laurentide Ice Sheet covered most of Canada and reached deep into the northern United States.<\/p>\n
They were here at a time when the most widely taught model for the peopling of the Americas said that the migration from Asia into North America had not yet begun, or had barely started.<\/p>\n
A single set of footprints in a dry New Mexico lake basin has become one of the most consequential pieces of evidence in one of the oldest and most contested debates in American science: who were the first people to reach the Western Hemisphere, how did they get here, and how long ago did they arrive?<\/p>\n
The answer has been changing, decade by decade.<\/p>\n
White Sands changed it again \u2014 and changed it in ways that are still being worked through by scientists, by legal scholars, and by Indigenous communities whose oral histories have always described a presence in the Americas that predates the timelines Western science has assigned them.<\/p>\n
The Landscape That Disappeared<\/p>\n
<\/p>\n
To understand what the footprints preserve, you have to understand the landscape they were pressed into \u2014 because that landscape is gone, and what replaced it is almost the opposite of what was there.<\/p>\n
White Sands National Park sits in the Tularosa Basin of southern New Mexico, a broad valley between the San Andres Mountains to the west and the Sacramento Mountains to the east.<\/p>\n
Today, the basin contains the largest gypsum dune field in the world \u2014 approximately 275 square miles of white gypsum sand that shifts and flows in the desert wind, covering the basin floor in a landscape that looks, from above, like a frozen white sea.<\/p>\n
It is one of the most striking landscapes in North America, and one of the most inhospitable.<\/p>\n
Rainfall is minimal.<\/p>\n
Temperatures reach extremes.<\/p>\n
The white gypsum reflects sunlight with punishing intensity.<\/p>\n
Water, apart from occasional monsoon rains, is absent.<\/p>\n
Twenty-three thousand years ago, none of that was true.<\/p>\n
The Tularosa Basin in the Last Glacial Maximum was a fundamentally different environment.<\/p>\n
The glaciers that covered the northern part of the continent altered weather patterns across the entire hemisphere.<\/p>\n
The Southwest was not glaciated \u2014 the ice sheets never reached this far south \u2014 but the climate was significantly cooler and wetter than it is today.<\/p>\n
Rainfall was higher.<\/p>\n
Evaporation was lower.<\/p>\n
<\/p>\n
The basin, which has no outlet to the sea (it is what geologists call a closed basin, where water that flows in has nowhere to go except evaporation), accumulated water over time into a substantial lake.<\/p>\n
That lake is called Lake Otero by geologists and researchers.<\/p>\n
At its maximum extent, it covered much of the central Tularosa Basin \u2014 a body of water potentially hundreds of square miles in area, relatively shallow but persistent, fed by runoff from the surrounding mountains and maintained by the cooler, wetter conditions of the glacial period.<\/p>\n
It supported aquatic plants, fish, and the kinds of ecological communities that productive shallow lakes in arid regions develop when conditions allow.<\/p>\n
Around its margins grew the vegetation that shallow lake shores produce: reeds, aquatic grasses, the bushy aquatic plant called Ruppia cirrhosa \u2014 sometimes called widgeon grass \u2014 that grows in brackish and saline water and would later become centrally important to the dating controversy.<\/p>\n
The lake margins were also, by every indication that has emerged from decades of research in the basin, a place where people lived, traveled, and left behind the marks of their passing.<\/p>\n
<\/p>\n
Among those marks: footprints.<\/p>\n
When the climate shifted at the end of the Ice Age \u2014 a process that took thousands of years and was not linear or smooth \u2014 Lake Otero contracted.<\/p>\n
The water receded.<\/p>\n
The lakebed sediments dried, hardened, and were eventually buried under accumulating layers of gypsum-rich material.<\/p>\n
The footprints, pressed into the wet lakebed mud when people and animals walked the shore, were sealed into those sediments and preserved in the dark, under increasing layers of overburden, for thousands of years.<\/p>\n
The gypsum dune field that covers much of the basin today formed from the minerals left behind as Lake Otero evaporated \u2014 gypsum dissolved from the surrounding rock, concentrated in the lake water, and deposited in massive quantities on the lakebed as the water disappeared.<\/p>\n
<\/p>\n
Wind picks up that gypsum and moves it across the basin in the dune field that tourists visit today.<\/p>\n
But beneath the dunes, and exposed in areas where erosion has stripped away the overlying material, the old lakebed remains.<\/p>\n
And in places where the old lakebed is exposed, the footprints come to the surface.<\/p>\n
What A Footprint Survives By<\/p>\n
The preservation of human footprints from 23,000 years ago is not, on its face, something that seems possible.<\/p>\n
Most organic material from that period is gone \u2014 eaten by bacteria, dissolved by groundwater, broken down by freeze-thaw cycles, scattered by wind and animals.<\/p>\n
<\/p>\n
Bone survives better than soft tissue.<\/p>\n
Stone tools survive better than bone.<\/p>\n
Most traces of human activity at that age have simply vanished.<\/p>\n
Footprints are, in some senses, the opposite of what you would expect to survive.<\/p>\n
They are impressions in soft material \u2014 by definition, material that was not hard when the impression was made.<\/p>\n
They require a specific sequence of events to persist: the material must be soft enough to take an impression, then must dry and harden without being disturbed, then must be buried quickly enough to avoid weathering, then must remain undisturbed underground long enough for the sediment to lithify or at least become stable, and then must be exposed in a controlled enough manner that the impressions survive the re-exposure process.<\/p>\n
<\/p>\n
At White Sands, all of those conditions were met.<\/p>\n
The lakebed sediments along the ancient shore of Lake Otero were fine-grained and cohesive \u2014 the kind of material that takes a crisp impression and retains it.<\/p>\n
The footprints were pressed deep enough to survive the initial drying process.<\/p>\n
The overlying sediments that accumulated after the lake level dropped buried them quickly enough to prevent weathering.<\/p>\n
And the erosion that has brought them back to the surface in the modern period is gentle enough \u2014 driven by wind removing soft gypsum rather than by water carving channels \u2014 to expose the impressions without destroying them.<\/p>\n
The result is that the footprint surfaces at White Sands are, in places, extraordinarily well preserved.<\/p>\n
<\/p>\n
Individual toes are visible.<\/p>\n
The ball of the foot leaves a distinct rounded impression.<\/p>\n
The heel strikes the sediment at an angle that reflects the normal human walking gait.<\/p>\n
In some trackways \u2014 sequences of connected footprints from a single individual walking in a consistent direction \u2014 researchers can measure stride length, step width, and the slight lateral tracking that characterizes different individuals.<\/p>\n
These are not abstract data points.<\/p>\n
They are the frozen, mineralized record of actual human movement.<\/p>\n
<\/p>\n
The people who made these impressions were walking, not running, in most of the preserved trackways.<\/p>\n
Some appear to have been carrying things \u2014 the depth and distribution of pressure in the footprints changes in ways consistent with added weight on one side of the body.<\/p>\n
Children ran alongside adults, their smaller footprints crossing and recrossing the larger ones in patterns that are recognizable to anyone who has walked a muddy path with a child in tow.<\/p>\n
The white-tailed deer, the mammoth, the giant ground sloth, and other Ice Age megafauna also left impressions in the same sediments.<\/p>\n
In some remarkable cases, human and animal trackways intersect \u2014 not because researchers placed them in proximity for dramatic effect, but because the same lakeshore that attracted people also attracted the animals they shared the landscape with, and the mud recorded all of them.<\/p>\n
Those intersecting trackways became one of the most discussed features of the White Sands site \u2014 not just because of what they implied about the age of human presence, but because of what they preserved about behavior.<\/p>\n
<\/p>\n
People and mammoths were using the same shoreline.<\/p>\n
Giant sloths left footprints that human footprints occasionally cross or circle.<\/p>\n
The evidence suggests, cautiously and with appropriate uncertainty, that the people walking this lakeshore were aware of the large animals around them and may have been observing, tracking, or interacting with them.<\/p>\n
This is the human center of the White Sands story.<\/p>\n
Not just a date \u2014 a date attached to actual people doing actual things in an actual landscape, preserved in extraordinary physical detail in a way that no number of stone tools or bone fragments could quite replicate.<\/p>\n
How The Footprints Were Found<\/p>\n
<\/p>\n
The formal scientific engagement with the White Sands footprints began with David Bustos, the resource program manager at White Sands National Monument (it became a National Park in 2019).<\/p>\n
Bustos had been working at White Sands for years and was deeply familiar with the landscape and its paleontological and geological features.<\/p>\n
He began noticing what appeared to be trackways in the exposed lakebed sediments \u2014 impressions that suggested animal and possibly human passage across the ancient surface.<\/p>\n
The site was remote enough and the exposures sufficiently limited that systematic investigation took time to develop.<\/p>\n
Bustos connected with researchers from the United States Geological Survey and from universities in the United States and United Kingdom, assembling a team capable of analyzing what the exposures might contain.<\/p>\n
Among those researchers was Matthew Bennett of Bournemouth University in the United Kingdom, a specialist in fossil footprint analysis with extensive experience in African sites preserving ancient hominin trackways.<\/p>\n
<\/p>\n
The team worked systematically across the exposed surfaces, mapping and documenting trackways, identifying individual impressions, and beginning the process of trying to establish what they had found and, crucially, when the footprints had been made.<\/p>\n
Dating the footprints directly \u2014 dating the actual sediment in which they were pressed \u2014 is technically challenging.<\/p>\n
The footprints themselves are not organic material; they are impressions in mineral sediment.<\/p>\n
What can be dated is the organic material found within the same sediment layers: seeds, plant fragments, organic carbon incorporated into the mud when it was fresh.<\/p>\n
If the organic material can be dated reliably, and if it can be shown to be contemporaneous with the sediment that preserves the footprints, then the footprints can be dated indirectly.<\/p>\n
The team focused on seeds of Ruppia cirrhosa \u2014 the aquatic plant that grew in and around Lake Otero \u2014 found within the sediment layers immediately above and below the footprint horizon.<\/p>\n
<\/p>\n
Ruppia seeds are small, identifiable, and widespread in lakebed sediments from this kind of environment.<\/p>\n
They are also organic, meaning they contain carbon that can be analyzed using accelerator mass spectrometry radiocarbon dating \u2014 the most precise available method for dating organic material up to about 50,000 years old.<\/p>\n
The radiocarbon dates from the Ruppia seeds returned ages in the range of approximately 21,000 to 23,000 years before the present.<\/p>\n
The team published their findings in the journal Science in September 2021.<\/p>\n
The title of the paper was understated in the manner of scientific publishing: “Evidence of humans in North America during the Last Glacial Maximum.” The findings were not understated at all.<\/p>\n
Why 23,000 Years Was Explosive<\/p>\n
<\/p>\n
To understand why the White Sands dates were so significant \u2014 why they were described in the press as potentially the most important archaeological discovery in a generation \u2014 requires understanding the intellectual framework they were disrupting.<\/p>\n
The conventional model for the peopling of the Americas had, for most of the twentieth century, centered on what is called the Clovis-first hypothesis.<\/p>\n
The Clovis culture is named after a site near Clovis, New Mexico, where distinctive fluted stone spear points were first identified in the 1930s in association with the bones of extinct Ice Age animals.<\/p>\n
Clovis points \u2014 large, beautifully made, with characteristic channels flaked into both faces of the point \u2014 have been found at sites across North America.<\/p>\n
They represent the most widespread and recognizable early stone tool technology in the New World.<\/p>\n
The oldest well-dated Clovis sites were approximately 13,000 years old.<\/p>\n
<\/p>\n
For decades, the Clovis-first hypothesis held that Clovis people were the first Americans \u2014 that they had crossed from northeastern Asia into Alaska via the Bering land bridge when low sea levels connected the two continents during the Ice Age, then moved south through a corridor between the retreating Laurentide and Cordilleran ice sheets as the glaciers began to retreat around 14,000 to 15,000 years ago.<\/p>\n
The model was elegant and had genuine evidential support.<\/p>\n
The Bering land bridge was real \u2014 it is documented by geology.<\/p>\n
The ice-free corridor was real \u2014 it opened as the glaciers retreated.<\/p>\n
Clovis technology spread across the continent rapidly and appeared at broadly similar times across a wide geographic range, which was consistent with a relatively rapid southward expansion of the first arrivals.<\/p>\n
And for much of the twentieth century, no site with convincing evidence of pre-Clovis human occupation had been accepted by the archaeological mainstream.<\/p>\n
<\/p>\n
But the consensus was already under serious pressure before White Sands.<\/p>\n
Monte Verde, a site in southern Chile excavated by archaeologist Tom Dillehay and his colleagues beginning in the 1970s, preserved organic material \u2014 wooden structures, plant foods, animal remains \u2014 that was dated to approximately 14,500 to 15,000 years ago.<\/p>\n
The site eventually received mainstream acceptance in the late 1990s, after years of skepticism and debate, as evidence of pre-Clovis human presence.<\/p>\n
But its location was the problem it created, not solved: Monte Verde is in southern South America, more than 10,000 miles from the Bering Strait.<\/p>\n
If people were there 15,000 years ago, they had to have been somewhere farther north considerably earlier \u2014 but where was the evidence of that earlier northern presence?<\/p>\n
The Paisley Caves in Oregon contained human coprolites \u2014 preserved ancient feces \u2014 that yielded DNA and radiocarbon dates suggesting human presence approximately 14,000 to 14,500 years ago, slightly predating or contemporaneous with the earliest Clovis sites and again suggesting people were in the interior of the continent earlier than the standard model comfortably accommodated.<\/p>\n
<\/p>\n
Other sites contributed to an accumulating picture.<\/p>\n
Debra L.<\/p>\n
Friedkin in Texas produced pre-Clovis tools dated to approximately 15,000 to 16,000 years ago.<\/p>\n
The Meadowcroft Rockshelter in Pennsylvania had been controversial since the 1970s, with claimed dates in the range of 14,000 to 19,000 years \u2014 dates that were contested for decades before some researchers concluded the evidence was genuine.<\/p>\n
Bluefish Caves in Yukon, Canada, produced cut-marked animal bones tentatively dated to approximately 24,000 years ago, though the evidence remains debated.<\/p>\n
Each of these sites pushed the timeline back in ways that the Clovis-first model struggled to accommodate.<\/p>\n
<\/p>\n
But none of them came from the Last Glacial Maximum \u2014 the period roughly 26,000 to 19,000 years ago when the ice sheets were at their maximum extent and the Bering land bridge itself was at its widest.<\/p>\n
White Sands did.<\/p>\n
A date of 23,000 years placed human presence in New Mexico at the height of the Last Glacial Maximum.<\/p>\n
Not after the glaciers began to retreat.<\/p>\n
Not in the period when an ice-free corridor might have been opening.<\/p>\n
During the coldest, most glaciated phase of the entire Ice Age \u2014 a period when the standard model would have said that not only were people not in New Mexico, they had not yet completed the transition from northeastern Asia into Alaska at all.<\/p>\n
<\/p>\n
This was not a modest revision.<\/p>\n
It was, if the dates held up, a fundamental challenge to the entire framework.<\/p>\n
It implied that people had been in the Americas for far longer than the Clovis-first model allowed, that the timing and route of the initial peopling had to be reconsidered, and that the archaeological record of the first Americans was either far older than existing evidence had shown or that large portions of it had been missed, lost, or not yet found.<\/p>\n
The Question That Followed The Discovery<\/p>\n
The 2021 Science paper was received with a mixture of excitement and caution that reflected both the significance of the claim and the standard scientific practice of scrutinizing extraordinary findings before accepting them.<\/p>\n
The excitement was genuine.<\/p>\n
<\/p>\n
The footprints were real physical evidence \u2014 not stone tools that could potentially be misidentified as human-made, not pollen samples or sediment chemistry that required multiple steps of interpretation, but the actual impressions of human feet in ancient mud.<\/p>\n
The anatomical details visible in the better-preserved tracks were consistent with modern human foot morphology.<\/p>\n
The trackways showed recognizable human walking behavior.<\/p>\n
The site was not someone’s imaginative interpretation of ambiguous evidence; it was relatively straightforward in its identification of human presence.<\/p>\n
The caution focused on the dating, and the concern was technically specific.<\/p>\n
The seeds of Ruppia cirrhosa used for radiocarbon dating are aquatic plant material.<\/p>\n
<\/p>\n
Aquatic plants are known to be susceptible to what is called the reservoir effect \u2014 a phenomenon in which organisms that live in or draw carbon from lake or river water can incorporate carbon that is older than the organism itself.<\/p>\n
Here is why that matters.<\/p>\n
Radiocarbon dating works by measuring the ratio of radioactive carbon-14 to stable carbon-12 in an organic sample.<\/p>\n
Living organisms incorporate carbon from the atmosphere (or, for aquatic organisms, from the water) continuously throughout their lives.<\/p>\n
When an organism dies, it stops incorporating new carbon, and the carbon-14 it contains begins to decay at a known rate.<\/p>\n
By measuring how much carbon-14 remains, laboratories can calculate how long ago the organism died.<\/p>\n
<\/p>\n
The problem with aquatic plants is that lake and river water can contain dissolved carbon that is significantly older than the water itself \u2014 old carbon derived from ancient limestone or other geological sources that dissolved into the water over long periods.<\/p>\n
If an aquatic plant is drawing some of its carbon from this old dissolved carbon rather than entirely from the atmosphere, the radiocarbon date of the plant will make it appear older than it actually is.<\/p>\n
The organism looks ancient because some of its carbon is ancient, not because it is.<\/p>\n
Skeptics raised this possibility explicitly after the 2021 publication.<\/p>\n
The Ruppia seeds used for dating were aquatic plant material from a closed basin with a complex geological history.<\/p>\n
The Tularosa Basin has abundant gypsum and other dissolved minerals.<\/p>\n
<\/p>\n
It is exactly the kind of environment where a reservoir effect might be expected to occur.<\/p>\n
If the Ruppia seeds had incorporated a significant amount of old dissolved carbon, the dates could be artificially inflated \u2014 and the actual age of the footprints could be substantially younger than 23,000 years.<\/p>\n
This was not a fringe objection.<\/p>\n
It was a mainstream scientific concern raised by legitimate researchers using standard analytical frameworks.<\/p>\n
And it was serious enough that it required a serious answer.<\/p>\n
The question was: could researchers find a way to test the dates using different materials that were not subject to the same potential contamination?<\/p>\n
<\/p>\n
The Follow-Up Evidence<\/p>\n
The scientific team that had published the original 2021 findings was aware of the reservoir effect concern and was already working to address it.<\/p>\n
In 2023, they published a follow-up paper in the journal Science that presented independent dating evidence using materials not susceptible to the aquatic reservoir effect.<\/p>\n
The 2023 study used two independent approaches.<\/p>\n
The first was the dating of conifer pollen extracted from the same sediment layers that contained the footprints.<\/p>\n
Pollen from terrestrial plants \u2014 plants that draw their carbon from the atmosphere rather than from lake water \u2014 is not subject to the aquatic reservoir effect.<\/p>\n
<\/p>\n
Conifer pollen is identifiable to a high degree of specificity and is commonly found in lake sediment cores, blown into the lake from surrounding terrestrial vegetation.<\/p>\n
If conifer pollen from the same layers as the footprints gave dates consistent with the Ruppia seed dates, it would suggest the earlier dates were not the product of a reservoir effect.<\/p>\n
The second approach used optically stimulated luminescence (OSL) dating of quartz grains from the sediment.<\/p>\n
OSL dating works on an entirely different physical principle from radiocarbon dating \u2014 it measures the amount of energy stored in the crystal structure of mineral grains by exposure to natural background radiation, which accumulates at a known rate after the grains were last exposed to sunlight.<\/p>\n
OSL dating is not subject to the carbon reservoir effect because it does not involve carbon at all.<\/p>\n
Both independent approaches returned dates consistent with the original Ruppia seed dates.<\/p>\n
<\/p>\n
The conifer pollen and the quartz grains both supported an age in the range of approximately 21,000 to 23,000 years for the footprint horizons.<\/p>\n
The dates were not identical \u2014 different methods applied to different materials in different parts of the site will always produce some variation \u2014 but they were broadly concordant, and they were concordant in a way that specifically addressed the reservoir effect concern.<\/p>\n
The 2023 results did not silence all skepticism.<\/p>\n
Scientific debates about something this significant rarely end with a single publication, however well-designed.<\/p>\n
Some researchers continued to note uncertainties in the luminescence dates and called for additional lines of evidence.<\/p>\n
The conversation in the scientific literature has continued.<\/p>\n
<\/p>\n
But the balance of evidence shifted substantially with the 2023 paper.<\/p>\n
The original finding was not a methodological artifact of the aquatic reservoir effect.<\/p>\n
The independent dating approaches supported the extraordinary conclusion: people were at White Sands during the Last Glacial Maximum, approximately 21,000 to 23,000 years ago, and the footprints they left in the mud of Lake Otero’s shore have survived long enough for modern scientists to read them.<\/p>\n
What The Numbers Actually Mean<\/p>\n
It is worth slowing down here, because the significance of this age range is easy to state and hard to fully absorb.<\/p>\n
Twenty-three thousand years ago, the Northern Hemisphere was in the grip of the Last Glacial Maximum.<\/p>\n
<\/p>\n
The Laurentide Ice Sheet \u2014 the massive continental glacier that covered most of Canada and reached into the northern United States \u2014 was at or near its greatest extent.<\/p>\n
Ice was miles thick over what is now Montreal, Chicago, and Boston.<\/p>\n
The Great Lakes did not exist as lakes \u2014 the basins they occupy were filled with glacial ice.<\/p>\n
Sea levels worldwide were substantially lower than today, because so much of the world’s water was locked in ice.<\/p>\n
The Bering land bridge was exposed \u2014 a broad, grassy plain connecting northeastern Asia to western Alaska, through which animals and people could move without crossing open water.<\/p>\n
The question of whether people were moving through that land bridge at 23,000 years ago is exactly what the White Sands dates complicate.<\/p>\n
<\/p>\n
The traditional Clovis-first model held that the movement of people from Asia into North America was constrained by the ice \u2014 that the glaciers blocked southward passage until an ice-free corridor opened around 14,000 to 15,000 years ago.<\/p>\n
But 23,000 years ago, that corridor did not exist.<\/p>\n
The glaciers were expanding, not retreating.<\/p>\n
The path that would eventually open through the interior of the continent was not available.<\/p>\n
If people were in New Mexico 23,000 years ago, they could not have arrived via an ice-free interior corridor that did not yet exist.<\/p>\n
They must have arrived earlier, by a different route, or both.<\/p>\n
<\/p>\n
The most commonly discussed alternative is a coastal route.<\/p>\n
The Pacific Coast of North America, during the Last Glacial Maximum, was partially glaciated in the north but may have had ice-free refugia \u2014 areas where the coast was accessible \u2014 that could have allowed people to move southward by boat or along the shore.<\/p>\n
This coastal migration hypothesis has been gaining support from multiple lines of evidence over the past two decades.<\/p>\n
The White Sands dates are consistent with it, though they do not prove it specifically.<\/p>\n
There is another possibility that some researchers have been reluctant to entertain: that people arrived in the Americas far earlier than either the Clovis timeline or the coastal migration timeline suggests \u2014 not 15,000 years ago, not 23,000 years ago, but perhaps 30,000 or even 40,000 years ago.<\/p>\n
A handful of sites have produced evidence that proponents argue supports this possibility, though most of these claims remain contentious.<\/p>\n
<\/p>\n
The White Sands dates, if they hold, make such earlier arrivals more plausible by demonstrating that people were in the interior of North America during the Last Glacial Maximum \u2014 which implies they had arrived before the LGM began.<\/p>\n
What the White Sands dates do not prove: they do not prove that the people who made these footprints were the first humans in the Americas.<\/p>\n
They prove that humans were present at this specific location at this specific time.<\/p>\n
Other sites might eventually demonstrate earlier presence elsewhere.<\/p>\n
The White Sands footprints mark a moment in the deep human occupation of this hemisphere, not necessarily its beginning.<\/p>\n
This distinction matters for how we understand the finding.<\/p>\n
<\/p>\n
It is not that a single set of footprints revealed who the first Americans were and when they arrived.<\/p>\n
It is that a single set of footprints demonstrated \u2014 with physical, tangible, immediately legible evidence \u2014 that people were in North America at a time when the standard model said they were not.<\/p>\n
The model had to change.<\/p>\n
The footprints did not need to answer every remaining question to make that change necessary.<\/p>\n
Tracks Of The Living And The Dying<\/p>\n
The human footprints at White Sands are extraordinary.<\/p>\n
<\/p>\n
The context in which they are found makes them more extraordinary still.<\/p>\n
The same sediment surfaces that preserve human trackways also preserve the tracks of animals that no longer exist \u2014 members of the Pleistocene megafauna that went extinct at the end of the Ice Age, between roughly 12,000 and 10,000 years ago, in a pattern that affected large mammals across the globe and for which the causes are still debated.<\/p>\n
In North America, this extinction event eliminated the mammoths, mastodons, giant ground sloths, American horses, American camels, short-faced bears, saber-toothed cats, and dozens of other species.<\/p>\n
At White Sands, some of those animals left their traces in the same mud that human feet pressed into.<\/p>\n
Giant ground sloths \u2014 megatheria, some of which reached the size of modern elephants \u2014 left footprints at White Sands that are remarkable in their own right.<\/p>\n
The sloth’s foot was wide and plantigrade, leaving a large, distinctive impression quite different from any modern North American animal.<\/p>\n
<\/p>\n
In several documented cases, human footprints appear within sloth tracks \u2014 people stepping into the depressions made by the enormous animal’s feet.<\/p>\n
This could indicate that people were following or tracking sloths, using the animal’s already-pressed impressions as convenient footholds in soft mud, or simply that both species were using the same path at different times.<\/p>\n
Columbian mammoths also left tracks at White Sands, some preserved in the same general sediment exposures as human footprints, though the precise stratigraphic relationship between mammoth and human trackways at this site is an active area of research.<\/p>\n
The presence of mammoth tracks in the same landscape as human tracks does not prove human-mammoth interaction at White Sands specifically, but it documents that people and mammoths shared this landscape \u2014 a fact with obvious implications for questions about whether human hunting pressure contributed to the megafauna extinctions, a debate that has continued for decades.<\/p>\n
The trackways also reveal more intimate details of the people who made them.<\/p>\n
One of the most discussed individual trackway sequences at White Sands \u2014 sometimes called the “mother and child” trackway, though that identification is interpretive rather than proven \u2014 appears to preserve an adult and a small child walking together.<\/p>\n
<\/p>\n
The adult’s stride changes in ways consistent with carrying a child part of the way, and the child’s tracks appear and disappear in patterns that could indicate the child was sometimes carried and sometimes walking independently.<\/p>\n
Researchers have been appropriately cautious about overstating this interpretation, but the physical evidence is striking and the pattern is recognizable.<\/p>\n
These are not abstract chronological data points.<\/p>\n
They are the traces of human lives \u2014 of people walking muddy shores, following or avoiding large animals, carrying children through difficult terrain, doing the ordinary and extraordinary things that humans do when they move through a landscape.<\/p>\n
The preservation of that behavior in physical form, at an age when such preservation seemed impossible, is what makes White Sands genuinely unprecedented in the North American archaeological record.<\/p>\n
The Ice Age World They Inhabited<\/p>\n
<\/p>\n
The world that the White Sands people inhabited was different from today’s New Mexico in almost every measurable dimension.<\/p>\n
The climate was cooler \u2014 estimates vary by region and time period, but temperatures in the American Southwest during the Last Glacial Maximum were perhaps 10 to 15 degrees Fahrenheit cooler than the modern average, with some estimates higher in some seasons.<\/p>\n
This cooler regime, combined with changed atmospheric circulation patterns driven by the ice sheets, produced significantly higher precipitation in what is now the arid Southwest.<\/p>\n
The evidence for this is abundant: ancient lake levels, pollen records from lake sediments, the geochemistry of cave formations called speleothems, and the distribution of plant species whose modern ranges are limited to cooler or wetter areas than the LGM Southwest.<\/p>\n
Lake Otero, at its maximum, may have been one of the largest lakes in the Tularosa Basin during this period.<\/p>\n
The exact extent of the lake during the human occupation represented by the footprints is not fully resolved \u2014 lake levels fluctuated over time, and the footprint horizons represent specific moments in a long and variable hydrological history.<\/p>\n
<\/p>\n
But the general picture is of a landscape substantially wetter, greener, and more ecologically productive than the modern desert.<\/p>\n
The vegetation around the lake was different from today’s desert scrub.<\/p>\n
Grasses grew more abundantly.<\/p>\n
Wetland vegetation \u2014 reeds, sedges, aquatic plants \u2014 fringed the lake margin.<\/p>\n
Trees that today grow at higher elevations may have extended into the valley floor in areas where water was available.<\/p>\n
The ecological community supported by this wetter, cooler landscape was richer than today’s, both in diversity and in total biomass.<\/p>\n
<\/p>\n
Into this landscape came, or more accurately, had already arrived into this landscape, the people whose footprints survived.<\/p>\n
We do not know how many people were in the Tularosa Basin at any given time during the Last Glacial Maximum.<\/p>\n
The footprints represent specific events \u2014 specific occasions when people walked specific sections of the lakeshore \u2014 not a census.<\/p>\n
A handful of individuals, walking over days or seasons, could have produced the trackway evidence that has been identified.<\/p>\n
Alternatively, the lake margin may have been a place of regular use by a larger regional population.<\/p>\n
The footprints cannot tell us which, though researchers continue to work on questions about site extent and intensity of use.<\/p>\n
<\/p>\n
What the footprints do tell us is that people were present here during a specific climatic and environmental phase \u2014 the Last Glacial Maximum and its immediate aftermath \u2014 and that they were engaging with the landscape in ways consistent with people who understood it.<\/p>\n
They were moving efficiently along the shore.<\/p>\n
They were in the company of children, which implies a level of environmental security inconsistent with purely exploratory travel through an unknown and dangerous landscape.<\/p>\n
The presence of children in these trackways is, in its own understated way, one of the most powerful pieces of evidence for established human presence: you do not bring children on first contact with a new and hostile environment.<\/p>\n
You bring them when the landscape is known and reasonably safe.<\/p>\n
What The Migration Models Must Now Account For<\/p>\n
<\/p>\n
The White Sands dates, taken together with the body of pre-Clovis evidence that had been accumulating over the preceding decades, force a reckoning with the existing frameworks for understanding how people arrived in the Americas.<\/p>\n
The Clovis-first model, already weakened by Monte Verde, the Paisley Caves, and other pre-Clovis sites, cannot accommodate a Last Glacial Maximum presence in New Mexico.<\/p>\n
The timeline is simply incompatible.<\/p>\n
If people were at White Sands 23,000 years ago, and if the ice-free interior corridor did not open until approximately 14,000 to 15,000 years ago, then the route through the ice that the Clovis-first model proposed is ruled out as the primary pathway for the people who made those footprints.<\/p>\n
The coastal migration model \u2014 the hypothesis that early Americans moved southward along the Pacific Coast, using boats or coastal terrain to move around the edge of the ice \u2014 becomes more attractive in light of White Sands, though it is not definitively proven by it.<\/p>\n
The Pacific Coast at 23,000 years ago was partially glaciated in the far north but may have had ice-free stretches in what is now British Columbia, Washington, and Oregon.<\/p>\n
<\/p>\n
People capable of maritime or coastal travel could potentially have moved along those stretches and into the continental interior.<\/p>\n
The challenge with the coastal route is evidence.<\/p>\n
Most of the coastline of 23,000 years ago is now underwater, submerged beneath the sea level rise that accompanied the melting of the glaciers.<\/p>\n
Sites that would have been on the coast at that time \u2014 exactly the sites that would provide the most direct evidence of coastal migration \u2014 are largely inaccessible to standard archaeological survey.<\/p>\n
Underwater archaeology in the relevant depth ranges is technically demanding and expensive, and has so far produced limited evidence, though the search continues.<\/p>\n
An alternative framework, sometimes called the “early entry” model, suggests that people may have arrived in the Americas well before 23,000 years ago \u2014 during a period when the glaciers were less extensive and the Bering land bridge was more accessible.<\/p>\n
<\/p>\n
Under this model, people may have been in Beringia or even in North America for tens of thousands of years before the Last Glacial Maximum, potentially surviving in refugia during the coldest phase and expanding southward and eastward as conditions improved.<\/p>\n
The White Sands dates are consistent with this model, though again they do not prove it.<\/p>\n
What all of these models must now account for is the physical fact of people in New Mexico 23,000 years ago.<\/p>\n
That fact is on the ground.<\/p>\n
It is in the sediment.<\/p>\n
It is visible to anyone who walks the exposed surfaces of the ancient Lake Otero lakebed under the right light conditions.<\/p>\n
<\/p>\n
The models can argue about how those people got there.<\/p>\n
They cannot argue that those people were not there.<\/p>\n
A Second Opening: The Question The Footprints Cannot Answer<\/p>\n
Around the time that the scientific community was processing the implications of the White Sands findings, a different kind of question was gaining attention \u2014 one that the footprints, however extraordinary, are not equipped to answer.<\/p>\n
Who were these people?<\/p>\n
Not in the genetic or tribal sense alone \u2014 though that is part of the question \u2014 but in the fuller sense.<\/p>\n
<\/p>\n
What did they know?<\/p>\n
What did they carry with them?<\/p>\n
What languages did they speak?<\/p>\n
What did they believe about the landscape they were moving through?<\/p>\n
What did they call Lake Otero, if they called it anything, in the language or languages they used?<\/p>\n
These questions have no answers.<\/p>\n
<\/p>\n
The footprints preserve behavior, not identity.<\/p>\n
The sediments preserve organic material that can be dated, not stories or names or songs.<\/p>\n
The ancient lakeshore of the Tularosa Basin gives up the impressions of feet but nothing more intimate than that.<\/p>\n
The scientific literature on White Sands has been appropriately cautious about attempting to link the ancient people of the footprints to any specific modern Native nation or community.<\/p>\n
The evidence is too old, the genetic record too sparse, and the complexity of fifteen to twenty thousand years of population history too great to support confident specific identifications.<\/p>\n
People moved, mixed, diverged, and merged across the millennia between 23,000 years ago and the historical period.<\/p>\n
<\/p>\n
The people who made footprints at White Sands during the Last Glacial Maximum are likely ancestral, in some general sense, to many of the peoples who were living in the Americas at the time of European contact \u2014 but the specific lines of descent are not knowable from the evidence currently available.<\/p>\n
What can be said, and what is important to say clearly, is this: Indigenous nations whose traditional territories and oral histories are connected to the American Southwest have their own understanding of deep human presence in this landscape that does not depend on the approval of Western archaeology.<\/p>\n
The Pueblo peoples, the Navajo Nation, the Apache nations, the Tohono O’odham, and other communities of the broader Southwest region have maintained continuous or near-continuous presence in the region for as long as their histories record, and their histories record a very long time.<\/p>\n
When researchers discover and publicize evidence of human presence at 23,000 years before the present, they are not discovering that people were here.<\/p>\n
Indigenous communities have never been under any illusion that people arrived recently.<\/p>\n
What the scientific findings provide, for those communities, is sometimes useful \u2014 evidence that can be cited in legal and political contexts, corroboration of traditional histories that Western institutions have systematically doubted \u2014 and sometimes beside the point.<\/p>\n
<\/p>\n
The antiquity of Indigenous presence in the Americas is not, from the perspective of Indigenous communities, a scientific question awaiting resolution.<\/p>\n
It is a known fact, preserved in oral traditions and ceremonies and ecological knowledge and the very physical landscape of a landscape that has been known and named and loved for as long as anyone can remember.<\/p>\n
The footprints at White Sands did not reveal a human presence that was unknown to Indigenous peoples of the Southwest.<\/p>\n
They revealed it to a scientific and public audience that had been operating with an incomplete model of that presence.<\/p>\n
That distinction matters for how we tell this story.<\/p>\n
The Archaeology That The Ice Swallowed<\/p>\n
<\/p>\n
One of the most consequential implications of the White Sands dates \u2014 and of the pre-Clovis evidence more broadly \u2014 is the recognition that the archaeological record of the earliest Americans is probably far more incomplete than previously assumed.<\/p>\n
If people were in New Mexico during the Last Glacial Maximum, they were presumably also in many other places.<\/p>\n
They would have camped, hunted, processed food, made and abandoned tools, died and been buried or otherwise left their remains behind.<\/p>\n
All of that material evidence from 23,000 years ago should, in principle, be findable.<\/p>\n
But much of it is not findable, for a fundamental geological reason: the rise in sea level that accompanied the melting of the glaciers submerged enormous areas of what was once dry land.<\/p>\n
The continental shelf of North America \u2014 the broad, shallow underwater platform that extends from the current coastline into the ocean before dropping off into deep water \u2014 was largely dry land during the Last Glacial Maximum.<\/p>\n
<\/p>\n
Sea levels worldwide were approximately 300 to 400 feet lower than today.<\/p>\n
The coastline of North America was many miles farther out than the current shoreline.<\/p>\n
If people were living along the coasts of North America 23,000 years ago \u2014 and the coastal migration model suggests they were \u2014 their camps and settlements were on land that is now under hundreds of feet of ocean water.<\/p>\n
Finding those sites is not impossible, but it requires deep-water archaeology, sophisticated search methods, and significant resources.<\/p>\n
Relatively little such work has been done, because the logistics and costs are daunting.<\/p>\n
The same logic applies to the interior.<\/p>\n
<\/p>\n
Site preservation at this age is poor in most environments \u2014 most organic material has decomposed, most surface sites have been buried or eroded away, and the specific conditions that allowed the White Sands footprints to survive simply did not apply to most of the landscape.<\/p>\n
The scarcity of sites from the Last Glacial Maximum may reflect a genuine scarcity of people, but it may also reflect the destruction of the evidence by time and geology.<\/p>\n
White Sands survived because of a specific combination of circumstances \u2014 fine-grained lakebed sediment, rapid burial, low-energy erosion re-exposing the surfaces \u2014 that allowed traces from this period to persist.<\/p>\n
Most comparable traces are gone.<\/p>\n
The absence of evidence is not, in this case, evidence of absence.<\/p>\n
It is evidence of the specific processes of preservation and destruction that operate over twenty thousand years.<\/p>\n
<\/p>\n
The recognition of this gap has changed how some researchers approach the question of ancient American populations.<\/p>\n
Rather than assuming that the current archaeological record represents a reasonably complete picture of early human presence, archaeologists are increasingly working to identify environments and site types where older material might have survived \u2014 underwater sites, cave deposits, lake sediments \u2014 and applying new methods to extract older records from those contexts.<\/p>\n
White Sands is, in this sense, a proof of concept.<\/p>\n
It demonstrated that evidence from the Last Glacial Maximum can survive in the right geological context.<\/p>\n
It raises the question of where other such contexts might exist, and what they might contain.<\/p>\n
The Park That Holds The Evidence<\/p>\n
<\/p>\n
White Sands National Park encompasses approximately 146,000 acres in the Tularosa Basin of Otero County, New Mexico.<\/p>\n
The park was originally designated as a National Monument in 1933, under the administration of Herbert Hoover, and was upgraded to National Park status in December 2019.<\/p>\n
Its primary claim to public attention has historically been the spectacular gypsum dune field \u2014 the largest in the world \u2014 that draws hundreds of thousands of visitors annually to sled down the white dunes and experience one of the most visually striking landscapes in the American Southwest.<\/p>\n
The paleontological and geological dimensions of the park have been studied for decades.<\/p>\n
The same geological processes that formed the dunes \u2014 the dissolution of gypsum from surrounding mountains, its transport in lake water, its deposition on the lakebed, and the subsequent wind transport of the dried gypsum across the basin \u2014 also preserved the fossil record that has been the focus of increasing scientific attention.<\/p>\n
Bear tracks, mammoth tracks, ground sloth tracks, and other Pleistocene megafauna traces were known from the park long before the human footprints became a focus of intensive study.<\/p>\n
<\/p>\n
The preservation of the footprint exposures is ongoing and requires management.<\/p>\n
The surfaces erode.<\/p>\n
New exposures develop as wind moves overlying material.<\/p>\n
The park service has worked with researchers to monitor and document the trackway surfaces, and the investigation of the site continues to expand in geographic scope as more surfaces are identified and studied.<\/p>\n
The total number of individual human footprints that have been documented at White Sands is now in the thousands, representing multiple trackway episodes across what appears to be a significant area of the ancient lakebed.<\/p>\n
The park faces the same challenge that all sites containing fragile and irreplaceable prehistoric evidence face: how to allow scientific study and public appreciation while protecting the material from damage.<\/p>\n
<\/p>\n
Human footprints in exposed sediment surfaces are, by definition, on the surface \u2014 visible, accessible, but also vulnerable to weathering, to the feet of visitors who might not recognize what they are seeing, and to the ordinary processes of erosion that will eventually destroy every exposure.<\/p>\n
The National Park Service has implemented visitor management protocols designed to balance access and protection.<\/p>\n
Some areas with documented trackways are closed to general visitor access.<\/p>\n
Interpretive programs explain the significance of the site and help visitors understand what they are seeing when they encounter preserved surfaces.<\/p>\n
The ongoing tension between preservation and access \u2014 a tension familiar to every national park \u2014 is particularly acute at a site where the evidence is both irreplaceable and, in the exposed form in which it has survived, impermanent.<\/p>\n
What The 2023 Results Changed And What They Did Not<\/p>\n
<\/p>\n
The 2023 follow-up study \u2014 using conifer pollen and quartz grain luminescence dating to provide independent confirmation of the Ruppia seed dates \u2014 substantially strengthened the case for the 21,000 to 23,000-year age range.<\/p>\n
But it is worth being precise about what changed and what did not.<\/p>\n
What changed: the primary methodological objection to the 2021 findings \u2014 that the Ruppia seed dates might be artificially old due to the aquatic reservoir effect \u2014 was addressed by independent dating approaches not subject to that effect.<\/p>\n
The concordance of multiple dating methods using different materials and different physical principles is the standard by which geochronological claims are evaluated, and the 2023 study brought White Sands significantly closer to meeting that standard.<\/p>\n
What did not change: the interpretation of the footprints as human remains well-established.<\/p>\n
What the 2023 study addressed was specifically the age question, not the identification question.<\/p>\n
<\/p>\n
Researchers had been confident from early in the analysis that the trackways were made by people \u2014 the anatomical details of the impressions, the biomechanical evidence of human gait, and the absence of any alternative explanation for the evidence were convincing well before the dating controversy arose.<\/p>\n
What remains in ongoing discussion: the precise age of the footprint horizons, which depends on the accuracy of the dating methods and their application to the specific sedimentary context of the White Sands site.<\/p>\n
Geochronology is a field in which precision improves with additional data, and additional data continues to be collected.<\/p>\n
The general age range \u2014 a human presence during the Last Glacial Maximum, broadly in the range of 21,000 to 23,000 years \u2014 has substantial support, but the specific figures will likely be refined as research continues.<\/p>\n
What the scientific community is watching: other sites that might provide additional evidence of human presence during the Last Glacial Maximum or earlier.<\/p>\n
If White Sands represents a population that was already established in the American interior at this time, that population had to have come from somewhere and had to have left traces in other places.<\/p>\n
<\/p>\n
Finding those traces \u2014 in underwater sites, in unexplored caves, in lake sediment records \u2014 is now a priority for researchers working on the earliest Americans.<\/p>\n
And what White Sands has definitively demonstrated, regardless of where the precise dating ultimately settles: that physical evidence from the Last Glacial Maximum can survive in specific geological contexts, that such evidence can be recognized and dated by modern methods, and that the story of when people first arrived in the Americas is more complex, more ancient, and more interesting than the Clovis-first model allowed.<\/p>\n
The Peopling That Never Stopped<\/p>\n
There is a way of telling the story of human arrival in the Americas that treats it as a single event \u2014 a migration, a crossing, a founding moment \u2014 and then moves on to what came after.<\/p>\n
The White Sands footprints complicate that narrative in ways that go beyond the specific age of the evidence.<\/p>\n
People did not arrive in the Americas once.<\/p>\n
<\/p>\n
The process of populating an entire hemisphere \u2014 two enormous continents with every kind of terrain and climate and ecological community \u2014 was not a single event or even a series of discrete events but a continuous process of movement, adaptation, and diversification that played out over thousands of years.<\/p>\n
The people who walked the shores of Lake Otero 23,000 years ago were not the end of a story about migration.<\/p>\n
They were part of a story about how people live and move and adapt that has no single beginning and no single endpoint.<\/p>\n
The genetic evidence from Indigenous peoples of the Americas, compiled over the past two decades through studies of both ancient and modern DNA, supports a picture of complex history.<\/p>\n
There appear to have been multiple founding populations \u2014 groups with distinct genetic signatures that diverged from each other at different points in the process of spreading through the hemisphere.<\/p>\n
The relationships between those founding populations and the specific times and routes of their movements are still being worked out, and the publication of each new ancient genome contributes something to the picture while usually complicating the picture at the same time.<\/p>\n
<\/p>\n
What the genetics agree on, and what the White Sands dates corroborate, is that the story is old.<\/p>\n
Considerably older than Clovis.<\/p>\n
Old enough to encompass the Last Glacial Maximum.<\/p>\n
Old enough to leave traces in the sediment of an ancient lake in New Mexico that twenty thousand years of geological change have not entirely erased.<\/p>\n
The footprints are not the first chapter of the American human story.<\/p>\n
They are one preserved page of a book that is mostly missing, documenting a moment in a process that had already been underway for some time and would continue for many thousands of years more.<\/p>\n
<\/p>\n
The people of the trackways \u2014 whoever they were, however they had arrived, whatever languages they spoke and beliefs they held \u2014 were part of a larger human history of this hemisphere that is still being recovered and still being understood.<\/p>\n
What Survives When Everything Else Is Gone<\/p>\n
There is something in the White Sands footprints that resists purely analytical treatment \u2014 something that is apparent when you read the descriptions of researchers first recognizing what the exposed surfaces contained.<\/p>\n
Twenty thousand years of geological history had passed between the moment when a person pressed their foot into wet mud on the shore of Lake Otero and the moment when a researcher at White Sands National Monument bent down to look more carefully at an irregular surface in the exposed lakebed and recognized it for what it was.<\/p>\n
In that interval, empires rose and fell and were forgotten.<\/p>\n
Languages that were once spoken by millions went extinct without leaving a record.<\/p>\n
<\/p>\n
Every person who had lived during that period had died, as had their children, and their children’s children, through hundreds of generations.<\/p>\n
The world had passed through the end of the Ice Age, the extinction of most of the large animals that had shared the Americas with these early people, the development of agriculture, the rise of cities, the invention of writing, the entirety of recorded human history, and the industrial transformation of the modern world.<\/p>\n
And the footprints were still there.<\/p>\n
Not because anything about them was specially protected.<\/p>\n
Not because someone had decided they were worth preserving.<\/p>\n
But because the specific combination of geological circumstances that surrounded them \u2014 the fine-grained sediment, the rapid burial, the low-energy erosion \u2014 had conspired to keep them intact through everything that had happened in the twenty thousand years since they were made.<\/p>\n
<\/p>\n
This kind of survival is not common.<\/p>\n
It is, in geological terms, extraordinarily rare.<\/p>\n
Most of the evidence of most of the people who lived on this planet before the development of durable material culture \u2014 stone tools, ceramics \u2014 is simply gone.<\/p>\n
The people of the Last Glacial Maximum left traces, but most of those traces did not survive the intervening twenty thousand years in any form we can read.<\/p>\n
What White Sands has given us is a window through which we can see, briefly and specifically, a moment from a period we would otherwise know only in the most general terms.<\/p>\n
A person walked across wet mud beside a lake in New Mexico twenty-three thousand years ago.<\/p>\n
<\/p>\n
Their foot pressed into the sediment.<\/p>\n
The mud dried.<\/p>\n
It hardened.<\/p>\n
It was buried.<\/p>\n
It stayed buried for twenty thousand years.<\/p>\n
And then the wind uncovered it, and someone was there to recognize what it was.<\/p>\n
<\/p>\n
That chain of contingency \u2014 the specific conditions that had to be met, the specific choices and accidents that led to the discovery \u2014 makes the White Sands footprints both extraordinarily precious and appropriately humbling.<\/p>\n
We know this much about these people: where they walked, roughly when they walked, that they walked with children, that they shared their landscape with animals that no longer exist.<\/p>\n
We know that they were here during a period when the standard model of American prehistory said they could not have been.<\/p>\n
We know almost nothing else.<\/p>\n
The footprints are a reminder of what is always true about archaeological evidence at this depth of time: the record is fragmentary, the silences are enormous, and what we know is always less than what happened.<\/p>\n
The people of White Sands had lives as complex and full and particular as any human lives.<\/p>\n
<\/p>\n
They had languages and stories and relationships and knowledge of the landscape they lived in that dwarfs anything the sediment record can preserve.<\/p>\n
They were not primitives or shadowy ancestors.<\/p>\n
They were people.<\/p>\n
The footprints in the mud of Lake Otero are the most direct evidence we have of that humanity.<\/p>\n
The heel, the arch, the toes, pressed into sediment twenty-three thousand years ago, surviving against every probability, finally seen.<\/p>\n
The Story That Isn’t Finished<\/p>\n
<\/p>\n
The research at White Sands continues.<\/p>\n
Each field season produces new data \u2014 new trackway surfaces identified and documented, new samples collected for dating, new analyses of the relationship between human and animal tracks in the same sediment horizons.<\/p>\n
The picture that emerges from this ongoing work becomes more detailed and more complex with each study.<\/p>\n
The broader pre-Clovis debate continues as well.<\/p>\n
Other sites are being investigated, other ancient genomes are being sequenced, other geological archives are being examined for evidence of human presence earlier than the Clovis horizon.<\/p>\n
The combination of improved ancient DNA methods, expanded application of luminescence and other non-radiocarbon dating approaches, and increased attention to site types and environments that might preserve earlier evidence is producing a steady stream of new findings that continue to revise the timeline and the migration models.<\/p>\n
<\/p>\n
What seems increasingly clear from this body of work is that the first Americans \u2014 whoever they were, however many founding populations contributed to the eventual diversity of the hemisphere’s people, however they navigated the routes that brought them to a new continent \u2014 were here considerably earlier than twentieth-century archaeology assumed.<\/p>\n
The Clovis horizon marks not the arrival of people in the Americas but a specific technological and cultural florescence whose relationship to what came before is still being worked out.<\/p>\n
People were here before Clovis, and White Sands proves they were here much earlier than anyone had previously demonstrated with such direct, physical, unambiguous evidence.<\/p>\n
The Indigenous peoples of the Americas have maintained, in their oral traditions and their relationships to the land, a sense of presence that is far older than anything Western archaeology initially credited.<\/p>\n
The Pueblo peoples of New Mexico live in a landscape they have occupied, in recognizable cultural form, for at least a thousand years, and their own histories extend the occupation considerably further.<\/p>\n
When they speak of their relationship to the land of the Southwest as ancient and fundamental, they are not using metaphor.<\/p>\n
<\/p>\n
They are describing something that the geological record of White Sands, however fragmentarily, now corroborates.<\/p>\n
The footprints are not the beginning of the story of human presence in the Americas.<\/p>\n
They are a window into a middle chapter of that story \u2014 the chapter we know the least about, the period that the ice and the sea and the ordinary destructive processes of geological time have done the most to obscure.<\/p>\n
Finding a window into that chapter, in the specific, physical, intimate form of human footprints in hardened lakebed mud, is a remarkable thing.<\/p>\n
It is also a reminder that the story is not finished.<\/p>\n
The landscape of the Tularosa Basin still holds secrets.<\/p>\n
<\/p>\n
The underwater archaeology of the submerged coastlines of the Last Glacial Maximum has barely begun.<\/p>\n
The ancient DNA record of early Americans continues to expand with each new ancient genome successfully extracted and sequenced.<\/p>\n
The pre-Clovis debate will continue to evolve as new evidence is found and new methods are applied.<\/p>\n
What White Sands established is that the debate should be about when people arrived and how they got here \u2014 not about whether they were here.<\/p>\n
They were here.<\/p>\n
The footprints prove it.<\/p>\n
<\/p>\n
They pressed into the mud of a lake that no longer exists, on a shore in a desert that was not yet a desert, at a time when the world was locked in ice and the models that would eventually try to explain their presence had not yet been dreamed of.<\/p>\n
They walked across the ancient shore of Lake Otero.<\/p>\n
They left their marks.<\/p>\n
The marks survived.<\/p>\n
We are only beginning to read what they say.<\/p>\n
The Science Of Reading Ancient Ground<\/p>\n
<\/p>\n
The study of fossil footprints \u2014 ichnology, from the Greek word for track \u2014 is a discipline that has developed far more rapidly than most people outside the sciences realize.<\/p>\n
Traditionally associated with dinosaur tracks, the field has expanded in recent decades to include the footprints of ancient humans and their close relatives, drawing on advances in three-dimensional surface scanning, photogrammetry, digital modeling, and the kind of biomechanical analysis that sports medicine and gait laboratories have developed for modern clinical purposes.<\/p>\n
At White Sands, these methods have been applied systematically to the trackway surfaces.<\/p>\n
Three-dimensional laser scanning captures the precise topography of individual footprints, recording depth, outline, and pressure distribution with a millimeter-scale precision that no hand measurement could match.<\/p>\n
Photogrammetric methods \u2014 in which multiple overlapping photographs are processed by software to generate three-dimensional models \u2014 can document large trackway surfaces quickly and with high fidelity.<\/p>\n
These digital records allow researchers to analyze the tracks at their leisure in the laboratory, to share data with collaborators around the world, and to preserve a record of surfaces that may degrade or be destroyed by continued weathering.<\/p>\n
<\/p>\n
The biomechanical analysis of the White Sands tracks has produced some of the most interesting behavioral inferences from the site.<\/p>\n
Human walking gait leaves characteristic signatures in the pressure distribution of a footprint \u2014 the heel strikes first, then weight rolls forward along the lateral edge of the foot toward the ball, then transfers to the toes for the push-off that propels the next step.<\/p>\n
This pattern is preserved in the depth and shape of well-preserved footprints in a way that allows researchers to distinguish normal walking from running, uphill from downhill movement, loaded from unloaded carrying, and even to estimate walking speed.<\/p>\n
Stride length \u2014 the distance between successive footprints of the same foot \u2014 is a function of both leg length and walking speed.<\/p>\n
For individuals of known stature and walking at a comfortable pace, stride length falls within predictable ranges.<\/p>\n
The stride length measurements from White Sands trackways have been used to estimate the general body size of the people who made them, with results consistent with anatomically modern humans of the size range common in the late Pleistocene.<\/p>\n
<\/p>\n
The analysis of trackways rather than individual footprints adds another dimension.<\/p>\n
When a single individual walks across soft ground in a consistent direction, the sequence of footprints reveals not just foot shape but the pattern of movement \u2014 whether the person paused, changed direction, or maintained a steady pace.<\/p>\n
At White Sands, some trackways appear to show individuals moving purposefully and in a consistent direction, suggesting travel across the landscape rather than activity at a fixed location.<\/p>\n
The intersection of multiple trackways \u2014 different individuals, possibly at different times, whose paths crossed on the same surface \u2014 adds information about group movement and landscape use.<\/p>\n
In some sections of the White Sands site, trackways from multiple individuals, including adults and children of different sizes, converge or parallel each other in ways that suggest group travel rather than solitary movement.<\/p>\n
The details are inferential \u2014 the sediment cannot tell us whether the people whose tracks intersect were traveling together or were at the location at different times \u2014 but the patterns are suggestive and have been carefully described by researchers.<\/p>\n
<\/p>\n
The intersection of human and megafauna trackways is particularly significant from a behavioral standpoint.<\/p>\n
At several documented locations within the White Sands site, human and ground sloth tracks appear on the same surface, in some cases with human tracks falling within the impressions left by the large animal’s feet.<\/p>\n
The interpretation of these intersections has been cautious: it could indicate that people were following or tracking the sloth, using its pre-pressed footsteps as convenient stepping places in soft mud.<\/p>\n
It could indicate that both species were using the same path at different times, so that the intersection of their tracks reflects independent use of the same route rather than direct interaction.<\/p>\n
Researchers have described one sequence \u2014 in which human tracks appear to circle the trackway of a large ground sloth, then converge on a location where the sloth’s track shows irregular pressure distribution consistent with the animal turning or stumbling \u2014 as potentially consistent with a hunting encounter.<\/p>\n
This interpretation has been stated carefully and with appropriate uncertainty, and it has not been presented as a definitive conclusion.<\/p>\n
<\/p>\n
But the possibility that what survives in the White Sands sediment includes actual frozen moments of human-megafauna interaction is one of the reasons the site has attracted such intense scientific interest.<\/p>\n
The same careful methodological approach has been applied to the dating question.<\/p>\n
Geochronology \u2014 the dating of geological materials and the events they record \u2014 is a field in which methodological rigor is paramount, because the stakes of getting the date wrong are high.<\/p>\n
At White Sands, the combination of radiocarbon dating of organic material and luminescence dating of mineral grains represents exactly the kind of multi-method approach that the field considers most reliable.<\/p>\n
When different methods, applied to different materials using different physical principles, converge on similar age estimates, the confidence in those estimates increases substantially.<\/p>\n
The White Sands geochronology is not yet final \u2014 no geochronological study ever truly is, because additional data always has the potential to refine or revise earlier results.<\/p>\n
<\/p>\n
But the convergent evidence from multiple dating approaches gives the research team and the broader scientific community good reason to take the Last Glacial Maximum ages seriously and to build additional research on the foundation that those ages provide.<\/p>\n
The Long Argument About Who Was First<\/p>\n
The debate about who the first Americans were and when they arrived is not new.<\/p>\n
It has been running, in various forms, for as long as Western scientists have been aware of the remarkable diversity and antiquity of Indigenous cultures in the Americas \u2014 which is to say, since at least the late eighteenth century.<\/p>\n
The earliest serious discussions of the antiquity of human presence in the Americas grappled with the fundamental question of how people could have reached two continents that appeared to be surrounded by ocean.<\/p>\n
The Bering Strait connection \u2014 the land bridge that geological evidence would eventually confirm as real \u2014 was proposed as a possible route in the eighteenth century, decades before the geological evidence for it had been assembled.<\/p>\n
<\/p>\n
The hypothesis was partly driven by physical similarity between northeastern Asian and some North American Indigenous populations that early observers noted, and partly by the logical requirement that people had to have gotten here somehow.<\/p>\n
In the nineteenth and early twentieth centuries, American anthropologists and archaeologists developed increasingly systematic approaches to the question, while also operating within the racial and cultural assumptions of their era \u2014 assumptions that often led them to underestimate the antiquity and complexity of Indigenous cultures.<\/p>\n
The search for evidence of an American Paleolithic \u2014 a stone tool culture comparable to the ancient stone tool traditions of Europe \u2014 was shaped by those assumptions in ways that sometimes led researchers to reject genuine evidence of great antiquity because it did not fit the expected pattern.<\/p>\n
The discovery of Clovis technology and its association with extinct Ice Age animals in the 1930s provided what seemed like a clean answer to the question of earliest Americans: the Clovis people, arriving approximately 13,000 years ago, were the first.<\/p>\n
The answer was accepted with varying degrees of enthusiasm, but it held the field for several decades, partly because it was supported by genuine evidence and partly because it was simpler than the alternatives.<\/p>\n
The gradual erosion of the Clovis-first consensus was not a dramatic overthrow but a slow accumulation of evidence that the model could not accommodate.<\/p>\n
<\/p>\n
Monte Verde in the 1970s and 1980s, Meadowcroft Rockshelter and its controversial dates, the Paisley Caves, the Friedkin site in Texas, and numerous other sites each contributed a piece of evidence that pointed in the same direction: people had been in the Americas before Clovis, and they had been there for considerably longer than the standard model allowed.<\/p>\n
But the pre-Clovis claims were often met with skepticism \u2014 sometimes legitimate methodological skepticism, sometimes what critics characterized as a systematic reluctance to abandon the Clovis-first framework.<\/p>\n
The bar for evidence of pre-Clovis occupation was set very high, and different researchers set it at different levels.<\/p>\n
What one group of researchers considered compelling evidence of pre-Clovis presence, another dismissed as ambiguous or contaminated.<\/p>\n
White Sands entered this debate with several advantages over many previous pre-Clovis claims.<\/p>\n
The evidence was not stone tools, which can be ambiguous \u2014 human-made or naturally fractured, the debates over some claimed pre-Clovis tools have lasted decades.<\/p>\n
<\/p>\n
The evidence was not pollen or phytoliths or sediment chemistry \u2014 material that is real but requires multiple steps of interpretation to connect to human presence.<\/p>\n
The evidence was footprints \u2014 the direct, physical, anatomically specific trace of human bodies moving across an ancient surface.<\/p>\n
You cannot misidentify a well-preserved human footprint as a natural geological feature.<\/p>\n
The anatomy is too specific: the characteristic elongation, the narrowing at the arch, the widening at the ball, the individual toe impressions in the better-preserved examples.<\/p>\n
Natural geological processes do not create these features in soft sediment.<\/p>\n
The identification of the White Sands trackways as human was, unlike many pre-Clovis claims, not a matter of serious dispute.<\/p>\n
<\/p>\n
The dispute was about the age.<\/p>\n
And that dispute, as described earlier, has now been substantially addressed by independent dating methods.<\/p>\n
The result is that White Sands has brought the pre-Clovis debate to a different kind of resolution than any previous site achieved.<\/p>\n
Not a final answer \u2014 archaeology does not work that way \u2014 but a convergent conclusion supported by multiple independent lines of evidence that is considerably more robust than most previous pre-Clovis claims could muster.<\/p>\n
What The Dunes Are Hiding<\/p>\n
The gypsum dune field at White Sands is one of the most visually spectacular features of the park, and it is also, in a very literal sense, hiding things.<\/p>\n
<\/p>\n
The dunes move.<\/p>\n
They are not static geological features but dynamic bodies of material in constant slow motion, driven by the prevailing winds of the Tularosa Basin from the southwest.<\/p>\n
The dunes advance across the basin floor at rates that have been measured and tracked over decades, burying terrain ahead of them and exposing terrain behind them as they pass.<\/p>\n
In the wake of the advancing dunes, deflation surfaces \u2014 areas where the wind has removed loose material and exposed underlying, more consolidated layers \u2014 develop and evolve over time.<\/p>\n
It is on these deflation surfaces, in the areas where the dunes have moved and the lakebed sediments beneath them have been exposed, that the footprint surfaces are found.<\/p>\n
The same process that created the dunes \u2014 the evaporation of Lake Otero and the wind transport of the resulting gypsum \u2014 also contributed to the conditions that preserved the footprints, and it is the ongoing movement of the dunes that is slowly re-exposing them.<\/p>\n
<\/p>\n
This means that the exposures are temporary.<\/p>\n
A surface that is visible this year may be covered again by advancing dune sand next year, or it may be further deflated and eventually destroyed by erosion over the following decade.<\/p>\n
The pace of new exposure and the pace of destruction are both continuing processes, and the management of the scientific resource at White Sands requires ongoing monitoring and rapid response when new surfaces appear.<\/p>\n
It also means that substantial portions of the ancient lakebed surface \u2014 including sections that may contain extensive additional trackways \u2014 are currently under the dunes, inaccessible to surface investigation.<\/p>\n
Ground-penetrating radar and other subsurface sensing methods have been used to begin characterizing what lies beneath the current surface, but the scale of the buried landscape is enormous relative to the resources available for its investigation.<\/p>\n
The implication is that what has been found so far at White Sands is almost certainly a fraction of what is there to be found.<\/p>\n
<\/p>\n
The exposures that have been documented represent those sections of the ancient lakebed that the specific pattern of dune movement has brought to the surface.<\/p>\n
Additional trackway surfaces, additional dating horizons, additional evidence of human and animal presence during the Last Glacial Maximum and adjacent periods, may exist in abundance beneath the dunes that have not yet been uncovered.<\/p>\n
This is not speculation \u2014 it is the straightforward implication of the geology.<\/p>\n
The dune field is a storage system as much as it is a covering system, and what it has stored from the thousands of years during which it was accumulating over the lakebed sediments may include far more evidence of the ancient occupation than has yet been seen.<\/p>\n
The future of research at White Sands will involve both continuing work on the surfaces that are currently accessible and developing methods to investigate the buried landscape more systematically.<\/p>\n
Non-invasive subsurface sensing, improved dating methods that require smaller sample sizes and can be applied to a wider range of materials, and the development of research partnerships between the park service, university researchers, and Indigenous communities are all part of how the investigation is likely to develop over the coming decades.<\/p>\n
<\/p>\n
The Question Of Continuity<\/p>\n
When scientists discuss the people whose footprints are preserved at White Sands, they are appropriately careful about connecting those ancient people to specific modern communities.<\/p>\n
The genetic and cultural diversity of Indigenous peoples in the Americas today is immense, the result of thousands of years of migration, divergence, mixing, adaptation, and historical contingency.<\/p>\n
Drawing a direct line from a group of people who walked a lakeshore 23,000 years ago to any specific modern nation or people requires evidence that does not currently exist.<\/p>\n
But the question of continuity \u2014 of the relationship between the ancient people of White Sands and the Indigenous peoples who have lived in the Southwest in historical and contemporary times \u2014 is not simply an academic question.<\/p>\n
It is a question with legal, political, and cultural dimensions that matter in real and immediate ways.<\/p>\n
<\/p>\n
The legal framework of the Native American Graves Protection and Repatriation Act, which governs the treatment of ancient human remains and cultural items found on federal land, requires assessments of cultural affiliation between ancient materials and modern tribes.<\/p>\n
The older the remains, the harder those assessments are to make with confidence \u2014 but the difficulty of making them does not eliminate the ethical and legal obligations involved.<\/p>\n
The footprints at White Sands are not human remains in the sense that NAGPRA primarily addresses \u2014 they are impressions, not bones or objects.<\/p>\n
But the people who made them are part of the human history of the American Southwest, and the Indigenous peoples of that region have legitimate interests in how that history is told, investigated, and interpreted.<\/p>\n
Several Native nations with traditional territories and cultural connections to the broader region of southern New Mexico have engaged with the White Sands research at various levels.<\/p>\n
The park service has conducted consultation with tribal nations in accordance with its federal obligations.<\/p>\n
<\/p>\n
The nature and extent of those consultations, and the specific concerns and perspectives that tribal representatives have brought to them, have not been published in detail \u2014 consultation processes often involve confidential communications that are not appropriate for public disclosure.<\/p>\n
What can be said is that the framing of the White Sands research in public communications has generally been more careful about Indigenous perspectives than earlier generations of archaeological reporting typically were.<\/p>\n
The language of “discovery” \u2014 implying that the footprints represent something unknown until researchers found it, rather than something that has always been part of the landscape that Indigenous peoples have known \u2014 has been used with some care, and in some contexts explicitly challenged.<\/p>\n
Indigenous oral traditions from across the Southwest describe an ancient, intimate, and spiritually significant relationship with the land that does not begin with European contact or with any horizon that Western archaeology has previously identified.<\/p>\n
The Pueblo peoples of New Mexico trace their presence in the region through the accounts of their ancestors and the evidence of their ancient villages and sacred sites.<\/p>\n
The Navajo Nation’s emergence narratives describe the Din\u00e9 as having come from within the earth itself, at the center of a sacred geography that encompasses the land they now occupy.<\/p>\n
<\/p>\n
The Mescalero Apache, whose traditional territory includes portions of the Sacramento Mountains bordering the Tularosa Basin, have their own histories of deep connection to this landscape.<\/p>\n
None of these traditions are straightforwardly reconcilable with the specific evidence from White Sands, nor do they need to be.<\/p>\n
They are not alternatives to the geological and geochronological evidence; they are different kinds of accounts of human relationship to place, operating within different frameworks and preserving different kinds of knowledge.<\/p>\n
What the White Sands research provides, at its best, is additional evidence of the depth of human presence in the Southwest \u2014 evidence that is congruent with the general claim of deep antiquity that Indigenous traditions have always made, even if it cannot speak to the specific identities or histories of specific modern communities.<\/p>\n
The challenge for researchers, communicators, and park managers is to present the White Sands evidence in ways that honor this complexity \u2014 that convey the scientific significance of the findings without appropriating the story of human presence in the Southwest as if it were a story that Western science discovered and now owns.<\/p>\n
The Children Running Along The Shore<\/p>\n
<\/p>\n
Return, at the end, to the footprints themselves.<\/p>\n
Not to the methods, not to the debates, not to the implications for migration models or the future of pre-Clovis research.<\/p>\n
Return to the physical reality of what was found in the lakebed sediment of the Tularosa Basin.<\/p>\n
Children were running.<\/p>\n
The evidence for this is in the stride length and the depth of the toe impressions in the smaller tracks \u2014 the characteristic pressure distribution of a running rather than walking child, preserved in sediment that hardened before the impression could be smoothed away.<\/p>\n
Running children leave a specific kind of track: the toe presses deeper, the heel is lighter or absent, the length of the step is disproportionately long for the size of the foot.<\/p>\n
<\/p>\n
These children were not walking carefully along a muddy shore.<\/p>\n
They were running, the way children run \u2014 because the mud was interesting, because there was somewhere to get to, because the animals ahead of them were frightening or exciting, or for no reason at all except that children run.<\/p>\n
Adults walked beside them.<\/p>\n
The larger footprints show the measured, even stride of adults moving at a moderate pace \u2014 not hurrying, not struggling with difficult terrain, but covering ground with the efficiency of people who knew where they were going and had reason to go there.<\/p>\n
Some of the adult tracks suggest individuals of substantial size; others suggest smaller individuals.<\/p>\n
The group whose tracks are preserved in any given trackway surface was not demographically uniform \u2014 it was a mixed group of the kind that human communities typically comprise.<\/p>\n
<\/p>\n
They walked beside a lake.<\/p>\n
The lake was real \u2014 its chemistry and extent and history are documented in the geological record of the basin.<\/p>\n
Its shores were lined with aquatic vegetation that would have moved in the wind that came off the water.<\/p>\n
The water itself would have reflected the sky, which 23,000 years ago was the same sky that covers the Tularosa Basin today, with the same sun and the same stars and the same seasonal rhythm of long winter nights and brilliant summer days.<\/p>\n
The giant ground sloths were there.<\/p>\n
The mammoths were there.<\/p>\n
<\/p>\n
The late Pleistocene megafauna of North America \u2014 species that would be extinct within ten thousand years, lost in a wave of extinction at the end of the Ice Age whose causes are still debated but whose reality is not \u2014 were alive and moving through the same landscape.<\/p>\n
Some of their tracks crossed the same lakeshore that the people were crossing.<\/p>\n
In at least one documented case, human tracks appear to circle and follow sloth tracks in a pattern that suggests awareness, attention, possible intent.<\/p>\n
The people were aware of the animals.<\/p>\n
They were aware of each other.<\/p>\n
They were aware, presumably, of the lake and the mountains and the patterns of weather and season that organized their lives.<\/p>\n
<\/p>\n
They had language.<\/p>\n
They had knowledge of the landscape that the footprints can only hint at \u2014 the knowledge that accumulates in a community that has been in a place for generations, that has watched the lake level rise and fall, that has learned where the good fishing is and where the dangerous animals gather and when the plants at the shore margin produce the seeds and berries that supplement the diet that the lake’s resources provide.<\/p>\n
They were not primitives at the dawn of human consciousness.<\/p>\n
They were people \u2014 fully human, cognitively modern, culturally complex \u2014 who lived in a landscape that they understood and that they were using in the purposeful, competent ways that the trackways document.<\/p>\n
The footprints do not preserve the full complexity of their lives.<\/p>\n
But they preserve enough to make clear that the lives were complex.<\/p>\n
<\/p>\n
Twenty-three thousand years later, in a desert that used to be a lake, researchers who had developed over centuries the specific methods needed to read what the sediment had preserved looked down at an ancient surface and saw the shape of a human foot.<\/p>\n
The connection between that ancient foot and that modern researcher crossed twenty-three thousand years, crossed the entire span of recorded human history, crossed every intermediate generation, and landed in a moment of recognition that neither science nor language has quite adequate words for.<\/p>\n
Someone was here.<\/p>\n
Someone had always been here.<\/p>\n
The footprints in the hardened lakebed of White Sands said something that the models and the timelines and the migration frameworks had not fully admitted: the story of human presence in the Americas is older and deeper and more continuous than the standard accounts had allowed.<\/p>\n
The desert holds the evidence.<\/p>\n
<\/p>\n
The sediment held it for twenty thousand years, waiting for the moment when someone would look down and understand what they were seeing.<\/p>\n
The dunes are still moving.<\/p>\n
New surfaces are still coming to light.<\/p>\n
The investigation is still ongoing.<\/p>\n
What else the ancient lakebed of the Tularosa Basin holds in its hardened sediment, what other moments of human life from the Last Glacial Maximum are waiting beneath the white gypsum, is not yet known.<\/p>\n
But the footprints that have already been found are enough to have changed the story permanently.<\/p>\n
<\/p>\n
They always were here.<\/p>\n
The mud knew it, even when the models did not.<\/p>\n
The Basin That Science Missed For Decades<\/p>\n
The Tularosa Basin was not an unknown or unstudied landscape before the footprint discoveries gained international attention.<\/p>\n
Quite the opposite.<\/p>\n
The basin has been the site of significant scientific investigation for well over a century, and the presence of ancient Lake Otero sediments has been documented by geologists for decades.<\/p>\n
<\/p>\n
The gypsum dune field itself has attracted research attention because of its unusual composition and the sedimentary processes that produced it.<\/p>\n
Paleontological surveys documented Pleistocene megafauna remains \u2014 mammoth, ground sloth, camel, horse \u2014 in the basin sediments, providing evidence of the rich Ice Age fauna that had lived there before the extinctions at the end of the Pleistocene.<\/p>\n
What was not recognized, or not prioritized, for much of this period of investigation was the potential of the exposed lakebed surfaces to preserve human trackways.<\/p>\n
This is partly a matter of disciplinary boundaries \u2014 geologists studying gypsum formation and glacial lake hydrology are not necessarily looking for human footprints, while archaeologists focused on the Clovis horizon and later cultural periods were not expecting to find evidence of human presence in Last Glacial Maximum sediments.<\/p>\n
The intellectual framework determined, to a significant degree, what could be seen.<\/p>\n
David Bustos’s recognition of the trackways as potentially significant represented a crossing of that disciplinary boundary \u2014 someone at the intersection of resource management, paleontology, and archaeology, working in a specific landscape with enough intimate knowledge of it to notice something that did not fit the expected pattern.<\/p>\n
<\/p>\n
The subsequent collaboration between Bustos and a research team that included ichnologists, geochronologists, and paleoecologists brought the tools needed to evaluate what had been found.<\/p>\n
The methodological innovation required to address the White Sands site was not, in most cases, the development of entirely new techniques.<\/p>\n
Rather, it was the application of existing techniques \u2014 luminescence dating, three-dimensional photogrammetry, isotopic analysis of sediment organic matter \u2014 to a site type and a time period where those techniques had not previously been systematically applied.<\/p>\n
The methods existed.<\/p>\n
The site needed researchers willing to bring them to bear on a question that the standard frameworks had not anticipated needed answering.<\/p>\n
This pattern \u2014 of evidence existing in the landscape, waiting for a researcher with the right combination of tools, knowledge, and framework to recognize and pursue it \u2014 is common in the history of archaeological discovery.<\/p>\n
<\/p>\n
The White Sands footprints did not emerge from the sediment on a schedule determined by scientific readiness.<\/p>\n
They emerged on a schedule determined by the dynamics of the dune field, which has been covering and uncovering the lakebed at its own pace regardless of human scientific activity.<\/p>\n
The question was always whether someone would be there, with the right knowledge and methods, when the surfaces appeared.<\/p>\n
The alignment of Bustos’s field experience with Bennett’s ichnological expertise and a geochronology team capable of addressing the dating questions was, in that sense, a fortunate coincidence \u2014 the right researchers in the right conversation at the right time.<\/p>\n
Different researchers, different circumstances, and the significance of the surfaces might not have been recognized for additional years or decades, or might have been noted and not followed up with the intensity the findings ultimately received.<\/p>\n
Science, like all human endeavors, is contingent in ways that its formal outputs \u2014 the published papers, the confident statements of results \u2014 rarely make visible.<\/p>\n
<\/p>\n
The White Sands story is a story about contingency as much as it is a story about method.<\/p>\n
The Accountability Of Evidence<\/p>\n
One of the features of the White Sands case that has drawn comment from researchers in related fields is the relative transparency with which the primary scientific team handled the dating controversy.<\/p>\n
The 2021 paper acknowledged the potential for a reservoir effect in the Ruppia seed dates and noted it as a limitation of the study.<\/p>\n
The 2023 follow-up paper was explicitly framed as an attempt to address that limitation with independent evidence.<\/p>\n
This is how science is supposed to work: present findings with their limitations, respond to legitimate criticism with additional evidence, and adjust conclusions as the evidence warrants.<\/p>\n
<\/p>\n
The White Sands team did this in a relatively public and relatively timely way, given the pace at which geochronological research necessarily moves.<\/p>\n
The result is a body of evidence that is more robust for having been challenged.<\/p>\n
The independent dating methods used in the 2023 study were chosen specifically to address the specific objection raised about the 2021 results.<\/p>\n
If those methods had returned substantially different ages \u2014 if the conifer pollen had dated to 13,000 years and the luminescence ages to 15,000 years \u2014 the conclusion would have been very different, and the reservoir effect hypothesis would have been supported.<\/p>\n
The fact that they returned ages concordant with the original results is meaningful precisely because the test was designed to be capable of falsifying the original claim.<\/p>\n
The broader debate about pre-Clovis sites has sometimes been characterized by less productive dynamics \u2014 critics setting the bar for evidence so high that no site could meet it, or proponents overstating the certainty of their findings.<\/p>\n
<\/p>\n
White Sands has benefited from a relatively constructive engagement between those who raised methodological concerns and those who addressed them, resulting in a richer and more defensible body of evidence than either the 2021 paper alone or the critical response alone would have produced.<\/p>\n
For readers who are not scientists, this process can look like confusion or contradiction \u2014 “scientists said one thing, now they say another, which is it?” But the revision of conclusions in response to new evidence is not confusion.<\/p>\n
It is the characteristic feature of a self-correcting system of knowledge.<\/p>\n
The White Sands story, including its dating controversy and its resolution, is an example of that system working as it should.<\/p>\n
The conclusion that emerged from this process \u2014 that people were at White Sands during the Last Glacial Maximum, approximately 21,000 to 23,000 years ago \u2014 is supported by more evidence and more methodological rigor than the original claim was, precisely because the original claim was challenged and the challenge was taken seriously.<\/p>\n
After The Glaciers Melted<\/p>\n
<\/p>\n
The people who walked the shores of Lake Otero during the Last Glacial Maximum were not the last people to use that landscape.<\/p>\n
As the climate warmed at the end of the Ice Age and the lake contracted over millennia, later populations continued to inhabit the Tularosa Basin and the surrounding region.<\/p>\n
The archaeological record of the Southwest from the post-glacial period through the historical era documents continuous and complex human occupation \u2014 changing cultures, changing technologies, changing settlement patterns, but persistent human presence in a landscape that has always demanded adaptation and rewarded intimate knowledge.<\/p>\n
The Archaic cultures that occupied the Southwest following the Pleistocene megafauna extinctions developed increasingly sophisticated relationships with the landscape’s plant and animal resources, eventually contributing to the development of the agricultural societies whose ruins are among the most impressive in North America.<\/p>\n
The Ancestral Puebloans \u2014 whose descendants include the modern Pueblo peoples of New Mexico and Arizona \u2014 built substantial stone architecture across the Colorado Plateau and the Rio Grande valley, leaving behind sites like Chaco Canyon and Mesa Verde that are among the most studied archaeological complexes on the continent.<\/p>\n
The connection between the White Sands people and these later cultures is not directly traceable from the current evidence.<\/p>\n
<\/p>\n
But the geographic and ecological continuity is real.<\/p>\n
The Tularosa Basin and its surrounding mountains have been inhabited by successive human populations for as long as the climate has permitted human life there \u2014 which is to say, for at least 23,000 years as now demonstrated, and possibly longer as additional evidence may eventually show.<\/p>\n
The modern Indigenous peoples of New Mexico and the broader Southwest are the inheritors of this long human history.<\/p>\n
Their presence in the landscape is not an addition to it or a recent claim on it.<\/p>\n
It is the continuation of the longest continuous human occupation of any landscape in the Western Hemisphere for which we have solid evidence.<\/p>\n
White Sands, in its most complete reading, is not a story about ancient people who lived in a lost world that has no connection to the present.<\/p>\n
<\/p>\n
It is a story about the depth of human presence in a landscape that is still occupied, still known, still the subject of Indigenous cultural and spiritual relationships that have been continuous through more time than Western archaeology previously acknowledged.<\/p>\n
The footprints in the ancient lakebed are separated from the present by twenty-three thousand years of geological and cultural history.<\/p>\n
But they are not separated from the Indigenous peoples of the Southwest by the claim that the ancient people were simply too old to be connected to anyone living today.<\/p>\n
The continuity of human presence in this landscape \u2014 documented now in the sediment itself, in the hardened lakebed mud that preserved the impressions of ancient feet \u2014 is the context within which the footprints must be understood.<\/p>\n
They were not left by people who vanished.<\/p>\n
They were left by people who stayed, in the most fundamental sense \u2014 whose presence in this landscape became the foundation for all of the human history that followed, including the history that is still being made by the living communities whose roots reach into the deep past that White Sands has made legible.<\/p>\n
<\/p>\n
The dunes are still white.<\/p>\n
The basin is still dry.<\/p>\n
The mountains still rim the horizon in every direction.<\/p>\n
And somewhere in the hardened sediment beneath the wind-blown gypsum, the record of a moment from twenty-three thousand years ago waits for the next wind to bring it to the light.<\/p>\n
What The Next Discovery Might Say<\/p>\n
The White Sands footprints did not end the search for the earliest Americans.<\/p>\n
<\/p>\n
They opened a new phase of it.<\/p>\n
In the years since the 2021 paper appeared, the pace of research on early human presence in the Americas has accelerated.<\/p>\n
The demonstration that physical evidence from the Last Glacial Maximum can survive in specific geological contexts has focused attention on identifying other such contexts \u2014 other environments where ancient evidence might have been preserved against the ordinary destructive processes of time.<\/p>\n
Lake and wetland sediments are particularly promising.<\/p>\n
The same conditions that allowed preservation at White Sands \u2014 fine-grained sediment, rapid burial, stable chemical environment \u2014 exist in other ancient lake basins across the American West and in underwater deposits along the continental shelf.<\/p>\n
Researchers studying lake sediment cores from Nevada, California, and other western states have identified sediment horizons from the Last Glacial Maximum that contain organic material and, in some cases, evidence of human activity.<\/p>\n
<\/p>\n
The systematic investigation of these records is ongoing.<\/p>\n
Cave sites remain important as well.<\/p>\n
Caves provide the kind of stable, dark, dry conditions that maximize preservation of organic material, and the cave record of human occupation in the Americas extends back well into the pre-Clovis period at multiple sites.<\/p>\n
The recovery of additional ancient DNA from cave sites \u2014 either from human remains or from sediment that preserves traces of ancient occupation \u2014 has the potential to add significantly to the genetic picture of early Americans.<\/p>\n
Underwater archaeology along the submerged continental shelf is perhaps the most challenging but potentially most rewarding frontier.<\/p>\n
The coastlines of the Last Glacial Maximum are now under water, but the seafloor preserves sedimentary records that extend back through the glacial period.<\/p>\n
<\/p>\n
Projects using remotely operated underwater vehicles, side-scan sonar, and sediment coring to investigate the submerged shelf are in various stages of development.<\/p>\n
Finding specific sites on a submerged landmass of enormous extent is daunting, but the technology for doing so is improving rapidly.<\/p>\n
Ancient DNA analysis continues to advance at a pace that has repeatedly surprised even specialists.<\/p>\n
Methods that were not technically feasible a decade ago are now routine.<\/p>\n
The analysis of ancient DNA from sediment \u2014 environmental DNA deposited by organisms passing through an area, not requiring actual human remains \u2014 has opened possibilities for documenting human presence in archaeological contexts where physical remains are absent.<\/p>\n
Applied to Last Glacial Maximum sediments in contexts where other evidence suggests human presence, environmental DNA analysis might eventually add biological detail to the picture that footprints and stone tools alone cannot provide.<\/p>\n
<\/p>\n
The White Sands footprints are likely not the oldest evidence of human presence in the Americas that will ever be found.<\/p>\n
They are the oldest robust, multiply-confirmed, physically direct evidence currently known.<\/p>\n
But the logic of the geological and biological record suggests that additional evidence \u2014 older, from different locations, preserved by different circumstances \u2014 may exist and may eventually be found.<\/p>\n
Each new finding will be evaluated against the standards of evidence that the White Sands case has helped establish: independent dating methods, clear identification of the evidence as human in origin, careful treatment of the implications for migration models, and respectful engagement with Indigenous communities whose histories are part of the story that the evidence illuminates.<\/p>\n
The search that White Sands reinvigorated is the oldest question in American science: how long have people been here?<\/p>\n
The answer keeps moving backward in time.<\/p>\n
Where it will eventually settle is not yet known.<\/p>\n
But the mud of an ancient lake in New Mexico, pressed by human feet twenty-three thousand years ago, is pointing the way.<\/p>\n","protected":false},"excerpt":{"rendered":"
Pressed Into Mud, Preserved For Twenty Thousand Years They are not large footprints. Most of them belong to…<\/p>\n","protected":false},"author":1,"featured_media":1389,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-1388","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-stories"],"_links":{"self":[{"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/posts\/1388","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/comments?post=1388"}],"version-history":[{"count":2,"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/posts\/1388\/revisions"}],"predecessor-version":[{"id":1391,"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/posts\/1388\/revisions\/1391"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/media\/1389"}],"wp:attachment":[{"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/media?parent=1388"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/categories?post=1388"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/laptopsvilla.com\/blog\/wp-json\/wp\/v2\/tags?post=1388"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}