Thursday, December 18, 2008

Should the Woolly Mammoth live in today’s world?

The woolly mammoth is an extinct species of elephant that lived in one of two places, the high arctic and northern Siberia, and had adaptations to survive the cold environments of the northern hemisphere. The most noticeable adaptation is the wool undercoat which had long flowing hair up to 35 inches on top. The mammoth had teeth adaptated to help grind the course grasses making up most of its diet. Compared to the modern day elephant, the depth of the mammoth’s skin was no different; however the woolly mammoth had sebaceous glands that secreted fat onto their hair as well as 8cm of fat under their skin providing excellent insulation.

Woolly mammoths disappeared in North America at the end of the last ice age with the mammoths in Siberia surviving for another 2,000 years. Research suggests the extinction of the mammoths resulted from both climate change as well as human hunting; however, climate change was the foremost cause.[i] The increase in temperatures at the end of the last ice age caused their habitat, the glaciers, to melt away. Hunting by humans is what finished them off.[ii]

Preserved frozen woolly mammoths have been found in northern Siberia that still contain soft tissue. This is very uncommon as it requires the mammoths to have been covered very quickly after death with some sort of liquid that was then frozen. This most likely happened when mammoths became stuck in quicksand or drowned beneath the surface of the snow. Death not due to starvation was confirmed by undigested food in the mouths and stomach of these frozen mammoths. More evidence suggesting drowning is provided by more than 9,000 bones coming from at least 156 different mammoths found in the same spot of the Berelekh River in Siberia suggesting that the mammoths, from which these bones came, got swept away in the river causing their death.[iii]

A intact baby mammoth of 7-8 months, named Dima, was found in 1977 in the Kolyma River in northeast Siberia. Research has shown that Dima died about 40,000 years ago, and Dima’s internal organs are very similar to the current elephant.[iv] In 1997 a family found a mammoth tusk sticking out of the ground in Siberia. The 20,380 year old carcass to which it was attached was excavated and flown to an ice cave in 2000 where defrosting began using hairdryers. In May of 2007, a 6 month old female mammoth that died 37,000 years ago was discovered in Russia. Only four complete mammoths have been found to date, however mammoth tusks are more “common” and of great interest in the trading market.

Recently people began asking the question, should the woolly mammoth live again? Researchers have announced this past week that they are nearly done sequencing the genome of the woolly mammoth.[v] Biochemist Stephan Schuster from Penn State says that using the genome to bring the mammoth back can be done within the next 10-20 years, but suggests that it might be unethical to do so. New York Times calls it the “$64,000 question.” Arguments against the cloning are that the mammoth would have to spend their entire life in the captivity of a zoo with artificial environments and that if we’re going to clone mammoths why not clone a Neanderthal Man? Scientists are almost done sequencing that genome too. However, others say that we are under obligation to reintroduce them to Earth because we played a prominent role in eliminating them from it in the first place. For our own sake, the techniques of bringing back mammoths are the same techniques that would allow us to clone replacements of our own damaged or diseased body parts.

The earth today does not contain the ecosystem that the mammoths once roamed, however Russian researcher Sergey Zimov plans to recreate the environment that the mammoths lived in before the ice age to defend his theory that climate change had nothing to do with the extinction of the woolly mammoth, but that it was all due to hunting.[vi] He calls this environment Pleistocene Park and hopes to one day introduce the mammoths to this environment through cloning.
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