Horses graze on the grounds of the Pleistocene Park outside the town of Chersky, Sakha (Yakutia) Republic, Russia, September 13, 2021. Sergey Zimov, a scientist, has championed a surreal idea to slow the thaw in one area of Yakutia by populating the Pleistocene Park with large herbivores including bison, camels and musk oxen. The idea is to mimic the region's ecosystem during the last ice age that ended 11,700 years ago. The animals, he says, trample the snow, making it much more compact so the frigid winter temperatures can freeze the soil and the snow does not act as a thick insulating blanket. Picture taken September 13, 2021. REUTERS/Maxim Shemetov SEARCH "PERMAFROST SHEMETOV" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES