Monday, January 24, 2011

A new ancestry for elephants

Changes in names and taxonomical classification are a common occurrence as our knowledge of species living and extinct expands. In fact, around 10% of all taxonomic names are changed every year (Nimis, 2001). The changes are mainly in the realm of microbiology where morphology is difficult to apply, but rarely in the realm of charismatic megafauna, e.g. elephants.

However, there has been a long ranging dispute on whether the African savannah elephant and the African forest elephant are merely subspecies of the African elephant (Loxodonta Africana), or whether the genus Loxodonta needs to be re-organised.

Recent work by Rohland et al. (2010) compared genetic markers of the genomes of the iconic woolly mammoth (Mammuthus primigenius) and the American mastodon (Mammut americanum) with the modern African savanna elephant, African forest elephant, and Asian elephant.

A surprising finding from our study is that the divergence of African savanna and forest elephants—which some have argued to be two populations of the same species—is about as ancient as the divergence of Asian elephants and mammoths. Given their ancient divergence, we conclude that African savanna and forest elephants should be classified as two distinct species.
As we see, there is no certainty in taxonomy. And there goes my favourite example of a stable taxonomic name.


Nimis, P. L. (2001), A tale from Bioutopia - Could a change of nomenclature bring peace
to biology's warring tribes?, Nature, 413(6851), 21, doi:10.1038/35092637.

Rohland N, Reich D, Mallick S, Meyer M, Green RE, et al. (2010) Genomic DNA Sequences from Mastodon and Woolly Mammoth Reveal Deep Speciation of Forest and Savanna Elephants. PLoS Biol 8(12): e1000564. doi:10.1371/journal.pbio.1000564

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