Last of the mammoths (1 Viewer)

Trump et a swan?

Wouldn't put it past him!


8-P

Things fall apart--an explicitly anti-Darwinian take on the demise of the mammoth. [Bit off-topic but I'd hadn't encountered these gentry before and was amused to find how much "Darwinism" they actually do accept.]

http://www.evolutionnews.org/2017/03/evolution-in-action-the-end-of-the-woolly-mammoth/

Anyway, time to bring the great beasts back!

fugl said:

With regard to your larger point, tiny populations have successfully been brought back from the brink, e.g., the Trumpeter Swan. Too early to say anything one way or another about the California Condor, a very analogous case to the mammoth, I would have thought.

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Is it? I thought the article explained that the Wrangel Mammoths were doomed by the fact that over thousands of years their progressive decrease in genetic diversity restricted the elimination of unfavourable mutations (and I would speculate that slow reproduction and lack of mega-predators to prune the poor adaptations contributed to this).

My understanding is that the California Condor decreased dramatically over an insignificant period of time due to Man's depredations on the local fauna, so that even though the turnover of individuals is faster, there has not been time for the same introduction of unfavourable mutations during the decline. So what we have now in the recovery phase could be more analogous to the boom-and-bust population cycles of rodents. Hope so anyway. :t:

John

Farnboro John said:

Is it? I thought the article explained that the Wrangel Mammoths were doomed by the fact that over thousands of years their progressive decrease in genetic diversity restricted the elimination of unfavourable mutations (and I would speculate that slow reproduction and lack of mega-predators to prune the poor adaptations contributed to this).

My understanding is that the California Condor decreased dramatically over an insignificant period of time due to Man's depredations on the local fauna, so that even though the turnover of individuals is faster, there has not been time for the same introduction of unfavourable mutations during the decline. So what we have now in the recovery phase could be more analogous to the boom-and-bust population cycles of rodents. Hope so anyway. :t:

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I dunno, the breeding biology and demographics of the two species seem reasonably analogous to me. Condors, like mammoths, are at the top of the food chain (adults essentially predation-free; some very limited subadult predation) and are extremely slow-breeding (age of first nesting attempt 6-8 years, single egg 2 out of 3 successive years thereafter, 40-50% nest success).

The current condor population of c.450--free and unfree--is entirely descended from the tiny remnant California population of 22 removed from the wild in the 1980s for captive breeding, and can't have much genetic diversity for natural selection to work with.

Rodent boom-and-bust cycles, I think, are not relevant here. Even during the bust-phase, overall numbers remain relatively high. If they didn't, given the ferocious mortality rates characteristic of rodent boom-and-bust populations, there'd be constant danger of extinction.

Bit of a mammoth task - surely not worth the effort?

Mammoths, cheetahs, mountain gorillas, pandas. Birds of a feather?

http://www.csmonitor.com/Science/2017/0303/New-discovery-reveals-mystery-of-the-woolly-mammoth

Pleistocene Park. Interesting article on a fascinating subject. . ..

https://www.theatlantic.com/magazine/archive/2017/04/pleistocene-park/517779/

Another example of a big (relatively) long-lived animal brought back from the brink. . ..

https://www.nytimes.com/2017/03/11/...l?smprod=nytcore-ipad&smid=nytcore-ipad-share

fugl said:

Another example of a big (relatively) long-lived animal brought back from the brink. . ..

https://www.nytimes.com/2017/03/11/...l?smprod=nytcore-ipad&smid=nytcore-ipad-share

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While simultaneously, via the late Lonesome George, demonstrating that this case has more to do with individuals' fitness than human good will and endeavour.

John