The discovery offers new information about how the mammoth steppe, a cold and dry biome that covered northern Europe and Asia, divided into three types of biological environments when the ice age ended about 11,700 years ago. The steppe, which was home to now-extinct species including the woolly mammoth and the woolly rhinoceros, separated into tundra, taiga — coniferous forest — and steppe.

“Our results support this theory since the diversification of the horned lark into these sub species seems to have happened about at the same time as the mammoth steppe disappeared,” Love Dalén, a professor at the Swedish Museum of Natural History and a research leader at the Centre for Palaeogenetics, said in a statement.

Researchers said the bird carcass will also help them better understand how the horned lark evolved. They said they hope to map its genome and compare it with the genomes of all other subspecies of horned larks.

For now, genetic analysis suggests the bird was an ancestor of a subspecies of horned lark in Siberia and another subspecies in Mongolia, Nicolas Dussex, a zoologist at Stockholm University, said in the statement.

Siberia has been the site of several frozen findings, many of which were studied by some of the same scientists who researched the horned lark. Last year, the researchers published studies of a 30,000-year-old severed wolf head and a puppy named Dogor that was frozen for 18,000 years.

In the broader Arctic, people have uncovered frozen mammoths, woolly rhinoceroses, horses, bison and wolverines, the researchers wrote in their new study. Paleontologists can use those remains to understand how climate change impacts those species and to study the evolution of a particular animal.

Although the scientists wrote that fossil ivory hunters’ methods of excavation can harm scientifically valuable animal remains, they said the preserved tissues and organs of frozen carcasses give them better information about gene expression than they can get from skeletal remains.

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