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Elephants -- the largest living terrestrial mammal -- began walking the surface of the Earth 5 to 10 million years ago in Africa. Today, there are fewer than 500,000 elephants alive, making this group of iconic animals a highly protected species -- especially in Africa where the perils of ivory trade continue to threaten them.
The shrinking population of elephants makes them an "isolated branch" in evolution, with only three currently recognized species: the Asian elephant, the African savannah elephant and the African forest elephant. A consortium of scientists used advanced sequencing technology to recover complete genomes from both living and extinct elephant species. In a paper, the authors provide a comprehensive genomic portrait of not just the living elephants but also members of extinct mammoths and straight-tusked elephants, as well as the American mastodon, an extinct distant relative of the elephant family. The paper reveals that gene flow between elephant species was a common feature of their history, contrary to previous studies which represented their relationships as a simple tree.Image credit: San Diego Zoo Global
