Global Warming Fuels Speedy Evolution

[sasha031]

Feb. 22, 2006 — Don't look now, but your backyard is evolving. It's no joke. There's a growing body of evidence that evolution is no longer something only seen either in this year's flu virus or Cretaceous tyrannosaur bones. It's happening everywhere, right now, and charging full-steam ahead. Research on toads, frogs, salamanders, fish, lizards, squirrels and plants are all showing evidence that some species are attempting to adapt to new conditions in a time frame of decades, not eons, say biologists.What's more, one of the biggest reasons for all this evolution right now may be that human-induced changes to climate and landscapes give species few other options.

Move, Adapt or Die
"Basically, a species can do three things," said the University of Sydney's Richard Shine: "go extinct, move or adapt." The first two have kept conservation biologists working day and night, to the exclusion of the third, he said. But that's changing as real-time evolution is hitting the news wires and getting more attention.The highest-profile case yet was made public by Shine and his colleagues in the Feb. 16 issue of Nature: the case of toxic cane toads at the forefront of a seven-decade Australian invasion. Measurements over the years prove that the leading toads have evolved significantly longer legs. It appears that hopping further and faster rewards long-legged toads with the first crack at lush virgin territory, and therefore more offspring to perpetuate their athleticism.

http://dsc.discovery.com/news/briefs/20060220/evolution_pla.html

[HereSince1628]

1. Folks you need to read about the Red Queen Hypothesis...

Which basically says species are ALWYAS running the evolutionary race as fast as they can and generally not getting anywhere.

Until the landscape changes all the running is typically running that goes no where just like the Queen and Alice did.

[phantom power]

2. Then there is also this interesting result...

Environmental stress exposes latent, accumulated variations, lying in wait. We may be privileged to see a lot of this. On some level, I'm a bit excited by the prospect of what we might learn about speciation.

What this tells us about evolution is that there can be a reservoir of 'invisible' variation in populations, which is typically buffered by developmental mechanisms. The buffering allows the variants to accumulate without compromising the viability of carriers. Enabling mutations or changes in the environment, however, can rapidly shift the effect of these variants out of the range that can be buffered, exposing new phenotypic effects that can then be subject to selection. This can be fast, fast, fast, since we aren't waiting for a single new mutation (or worse, for polygenic traits, many mutations) to expand into a population, but are exploiting a large pool of diversity that is already present, mixing extant alleles by recombination to produce new phenotypes.

http://scienceblogs.com/pharyngula/2006/02/evolution_of_a_polyphenism.php#more

[Dead_Parrot]

3. A deep, dark level, I assume...

Personally, I've found out what "oh, fuck" really means. Serves me right for reading E/E, I guess :)

edit: hey, new sig...

[phantom power]

4. It's an appalling way to learn about evolution. But maybe effective?

[Dead_Parrot]

5. Could be, could be...

although something like 99.99% of all species have gone extinct...

[phantom power]

6. Hmm... 99.99%... But we'll be different... I KNOW we will!

[Dead_Parrot]

7. Yeah. None of the others had Fox News. nt

[megatherium]

8. I remember reading Beak of the Finch, where the Galapagos finches

had measurable changes in beak length in several generations (like 11% change) as climate shifted on the islands. Beak length is basically all genetic, and so the researchers observed a pretty hefty bit of evolution right in front of them, in just a decade or two.

[Dead_Parrot]

9. You should read up on Drosophila speciation....

The little buggers do it in a couple of years, IIRC...

[megatherium]

10. I have read that. The classic experiment that introduced a breeding

population into a container with a known carrying capacity for drosophila. The population curve followed a nice smooth logistic curve, but then went up another notch: they evolved to become a bit smaller, to use less energy; so the carrying population increased. A smart bit of evolution (a change in the population genetics). This took 70 weeks, if memory serves (these guys reproduce in a two-week cycle). Isn't science cool?

[Dead_Parrot]

11. Science is indeed cool...

...but very unpopular when it produces answers. Alas...