Mammoths of Wrangel Island: Genetic resilience but sudden demise

10,000 years ago, on Wrangel Island, off the coast of Siberia, a unique population of mammoths began to form. Scientists have published their findings in the journal "Cell" and speculate on how these animals became extinct.

Scientists from the international research team found that a few, a maximum of eight, of these prehistoric animals were cut off from the continent by the rising sea levels. As a result, mammoths survived on this isolated island for the next few thousand years.

Data analysis shows that over approximately 20 generations, the mammoth population on Wrangel Island grew to between 200 and 300 individuals. However, their DNA studies indicated that these animals engaged in inbreeding, resulting in low genetic diversity.

Nevertheless, scientists believe these factors may not have led to their extinction. "We can now confidently reject the idea that the population was simply too small and that they were doomed to go extinct for genetic reasons," explains Love Dalén, an evolutionary geneticist from the University of Stockholm and co-author of the publication.

Dalén adds that the probable cause of the mammoths' extinction on Wrangel Island was an unforeseen event. If it had not occurred, the mammoths might still be living there today.

The research team conducted a genomic analysis of 21 woolly mammoths — 14 from Wrangel Island and seven from the continental population. The samples covered the last 50,000 years of these animals' existence.

Compared to their continental ancestors, the genomes of Wrangel Island mammoths showed signs of inbreeding and low genetic diversity. The studies also revealed decreased diversity in a group of genes that plays a crucial role in the immune response.

The genetic diversity of the island's population declined over six thousand years, but this process was slow. This suggests that the population size remained stable until its extinction.