Saturday 25 April 2015

Complete genome of two woolly mammoths sequenced

Mammoth DNA made it into the news again. Until recently, the genome of Mammuthus primigenius was not completely resolved yet, but now it is - not only of one individual, but actually two. These two individuals, both males and from Siberia, lived about 40.000 years apart from each other. The older one is from approx. 44,800 years ago, late Pleistocene, and the other one 4,300 years ago. The younger one lived on Wrangel Island, the last refuge of the Woolly Mammoth, back the time when the ancient Egyptians built their pyramids (which is a fascinating thought to me). 
The study, published by Palkopoulou et al.[1] in Current Biology, revealed interesting but not surprising facts. The population of the Eurasian woolly mammoth went through a considerable bottleneck during the middle Pleistocene, which is consistent with the fact that their habitat had shrunken dramatically back this time due to the interglacial climate [2]. The same happened at the early Holocene of course, but still mammoths survived into the antiquary. The last refugee population on Wrangel had a rather small genetic diversity, and likely also suffered from an inbreeding depression, which is confirmed by this study. Undoubtedly it was a mix of several factors that drove the last mammoths to extinction, but I think it is likely that man played a considerable role in it. In my opinion, perhaps not the vulnerable Wrangel population but at least the core population in the North Siberian tundra might have survived without any human hunting pressure. 

[1] Palkopoulou et al.: "Complete genomes reveal signatures of demographic declines in the Woolly Mammoth", Current Biology 2015.
[2] Nogues-Bravo et al.: "Climate change, humans, and the extinction of the Woolly Mammoth", PLOS Biology, 2008.

2 comments:

  1. Good news. Aside from this; if they really plan to not only clone a mammoth but also create a viable population, given the long gestation and maturing time of these animals, they should really start setting up fairly large surrogatemother-elephant-herds in more northerly latitudes. That way the new mammothpopulation can get a flying start and not just linger as a laboratoryexperiment. I suppose in many temperate areas in europe, asia and north-america elephants can kept outdoors at for at least part of the year.

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