The woolly mammoths of Wrangel Island were resilient creatures. Stranded on a remote island in the Arctic Ocean when sea levels rose, they were the last of their kind to die out. It was previously believed that they succumbed to extinction due to inbreeding, as genetic mutations spread among them, causing their demise. However, new research published in the journal Cell on June 27th challenges this theory.
Genetic diversity is like an insurance policy for a species. Having a variety of unrelated individuals in a population increases the chances of one possessing a heritable trait that can protect it from threats. If this trait can be passed down to offspring, the species can survive. In contrast, when small isolated populations are forced to interbreed over many generations, harmful mutations accumulate and lead to what is known as mutational meltdown. This process can result in the extinction of entire populations.
The new study suggests that the woolly mammoths of Wrangel Island did not actually die out due to inbreeding, but rather a different factor. This challenges the traditional explanation and sheds light on the importance of genetic diversity in ensuring the survival of a species. It serves as a reminder of the delicate balance required for species to thrive in their environment.