A lost savanna sea
The Alakol Basin, today a landscape of vast steppe and saline lakes, looked very different during the Neogene Period. Between 9.5 and 5.5 million years ago, in the Late Miocene epoch, this area was a subtropical woodland and open grassland, part of a widespread ecosystem known as the Pikermian biome. Fossil pollen and sedimentary evidence show a mosaic of wooded areas, glades, and river margins, all supporting a diversity of life. This environment, warmer and wetter than today, was sustained by a different configuration of seas and mountains. The basin itself was part of a larger trough that once held ancient seas and, during the Miocene, developed into a system of large, shallow lakes that created ideal conditions for preserving the bones of animals that died near their shores.
The fossil beds here, part of a geological layer known as the Chul'adyr Formation, contain a menagerie of extinct creatures. These fossil assemblages correspond to the Turolian age of the Late Miocene, a period between roughly 9 and 5.3 million years ago, when this particular fauna thrived across Eurasia. The concentration of bones suggests that herds of large mammals congregated in the basin, drawn to the water and abundant vegetation.