A brief note on the other remarkable animals of Santarosae in the terminal Pleistocene — the pygmy mammoths — because they appear in the same general timeframe and the same general landscape as the Arlington Springs individual, and their presence illuminates the environment that person entered.

Pygmy mammoths evolved on the Channel Islands from the Columbian mammoths that reached the islands during periods of lower sea level.

Isolated on the island, cut off from mainland gene flow, the mammoths’ size decreased over generations — the island rule, the ecological tendency for large species to shrink when island resources are limited.

The pygmy mammoths of the Channel Islands were substantially smaller than their mainland relatives: roughly the size of modern Asian elephants rather than the massive proportions of Columbian mammoths.

These animals were alive on Santarosae during the terminal Pleistocene, overlapping in time with the earliest documented human presence.