Woolly mammoths experienced a genomic meltdown just before extinction
(PHYSorg.com Archaeology & Fossils)

Dwindling populations created a `mutational meltdown` in the genomes of the last wooly mammoths, which had survived on an isolated island until a few thousand years ago. Rebekah Rogers and Montgomery Slatkin of the University of California, Berkeley, report these findings in a study published March 2nd, 2017 in PLOS Genetics.