An 8-year-old girl discovered the bones of a woolly mammoth and a prehistoric bison after a landslide along the banks of a river in western Russia.

Woolly mammoths (Mammuthus primigenius) were found on the Russian mainland until around 10,000 years ago, and survived on the remote Wrangel Island until their extinction 4,000 years ago.  (Image credit: Gerald Corsi/Getty Images)

An 8-year-old girl in Russia has discovered a set of mammoth leg bones, as well as a vertebra from a prehistoric bison while fishing with her father along the shores of the Oka River near Novinki, western Russia.

According to translated Russian news reports, Maryam Mirsaitova noticed a series of strange objects that had been unearthed by a recent landslide. Her father sent photographs to the nearby Nizhny Novgorod Museum-Reserve in the hope that researchers might identify her discoveries.

As it turned out, she’d found the condyle, or knee joint, and lower tibia of a woolly mammoth (Mammuthus primigenius). The bones were reasonably well preserved, with spongy tissue exposed by degradation in the sediment. The size of the bones indicates that they belonged to a large adult mammoth. The researchers suggested the animal likely lived around 100,000 years ago.

Woolly mammoths were common in the frigid northern regions of Europe and Asia beginning around 700,000 years ago, and later in northern North America around 100,000 years ago. In the region where Maryam found the fossils, mammoths likely persisted until about 10,000 years ago — when the end of the ice age caused these cold-adapted megafauna to lose their habitat and food sources. Human hunting may have accelerated their extinction.

Relict populations survived on Wrangel Island in Russia until around 4,000 years ago, where they became isolated and likely died out due to the effects of inbreeding.

Russia is rich in mammoth fossils, particularly in Siberia. Some specimens have even been mummified — a result of frigid environmental conditions that slow decay. Notably, a mummified mammoth calf later named Lyuba was discovered on the Yamal Peninsula in 2007.

Maryam’s finds also included a vertebra from what is likely a steppe bison (Bison priscus), which thrived in Europe, Asia and North America during the Pleistocene epoch (2.6 million to 11,700 years ago). It is an ancestor of the modern European bison (Bison bonasus) and American bison (Bison bison).

In a translated post on VK, the Nizhny Novgorod Museum-Reserve said Maryam had also found a bone belonging to an animal that’s yet to be identified.

The museum staff urged others who find fossils to come forward and report them to scientific institutions. Many fossils end up in private hands and are thus unavailable for study. Lyuba, for example, was traded by the cousin of the reindeer breeder who discovered her for a pair of snowmobiles. She was later recovered by law enforcement, then transferred to a Russian museum — and later traveled the world as part of an exhibit about mammoths.