The specific mix of plants and animals in any given location in the early Holocene was not the same as the modern mix.

At an elevation of roughly 10,700 feet — the elevation of Hourglass Cave — the landscape in the early Holocene would have been broadly similar to the modern alpine and subalpine environment: rocky terrain, sparse vegetation, cold nights even in summer, brief growing seasons, and the specific combination of high solar radiation and low atmospheric density that characterizes high-altitude environments.

Large patches of snow would have remained into summer in many north-facing slopes and sheltered basins.

The animal communities of the high country were somewhat different from the modern fauna.