Read more Could someone explain the importance of this in layman terms so I can understand it better please.
Actually, there are a lot of big fat red flags in this. First: press conference before any paper is out. I cannot think of a time that this has been a productive approach. Second: every time in the past some "radical new" mechanism which "overturns our understanding of evolution" has been touted, it has turned out to be a wash. Actually, evolutionary biologists are pretty good at figuring out their own field, and when something new comes along, it's (a)in the journals first, and (b)generally seen to fit very well with other mechanisms, even when it is surprising. Examples would be the discovery of lateral gene transfer between plant parasites and plants, and lateral gene transfer between infectious disease agents and hosts, and the ability of some organisms to "repair" a gene back to an original form after a "permanent" mutation. Third, and most profoundly damning: ""The discovery answers an age-old question that has puzzled biologists since the time of Darwin: How can organisms be so exquisitely complex, if evolution is completely random, operating like a 'blind watchmaker'?" from Chakrabarti. ::headdesk:: ::headdesk:: ::headdesk:: ::headdesk:: ::headdesk:: Sorry, but, no. Wotta pillock. Evolution is not "completely random", and the only people who make that claim are either creationists or ignoramuses (not mutually exclusive, I know). and Darwin did a very good job of answering the question of appearance of complex traits himself, as did quite a few contemporaneous scientists once they were looking in the right direction. There is nothing about organisms becoming so "exquisitely complex" which is "an age-old puzzling question to biologists." Oh, and fourth: even a cursory search under PubMed and in the bigger databases of biology and life-sciences literature turns up a huge quantity of papers on the evolution of evolvability -- multiple mechanisms which act as brakes, enhancers, guides or feedbacks on evolvability, and how these evolved, themselves. So, no, this isn't some astonishing revolution, although I can guess that the Intelligent Design crowd will be all over it. What it appears to be is a bunch of oblivious twonks going for hype, and Princeton not getting enough people from their own biology dept. to vet the press release.
The extraordinary thing is that scientists accept evolution and in the same breath deride the expanding Earth. The Theory of Evolution requires an expanding Earth. "Biogeographic arguments for a closed Pacific (just like biogeographic arguments for a closed Atlantic and closed Indian) are based on evolutionary theory. Specifically, according to the theory of evolution, you can't have a host of closely-related, poor dispersing taxa suddenly appearing on opposite sides of an ocean -- when it is highly improbable for any of the ancestral taxa to cross oceans. So according to the referenced paper above, unless plate tectonic theorists want to rely on divine intervention, a slew of creation stories or a myriad of impossible trans-oceanic crossings of terrestrial taxa, their paleomaps are wrong. Panthalassa could not have existed between all of the hundred plus referenced taxa, which is to say, it didn't exist." -- Dennis D. McCarthy, geoscientist, October 2003
Genuine nutter. Please Register or Log in to view the hidden image! After a few posts from OilIsMastery it's not hard to tell at all.
How did marsupials "evolve" in South America? Spontaneously? Please Register or Log in to view the hidden image! "Whenever you find yourself on the side of the majority, it is time to reform." -- Mark Twain, author, 1904
The mechanism found does not "guide" evolution, it resists evolutionary change. Which does indeed help answer a question that hasn't been completely answered yet: what all slows evolutionary change down, even stabilizing individual species for millions of years ?
Do you really need some sort of special explanation for that? Simply pausing and thinking on how evolution by natural selection works should answer this question.
Sort of, yes. The situation is as follows: we know that there are unfilled niches, or inefficiently filled roles, in sufficiently large ecosystems, that have been more or less available for millions of years. And there are species around in those ecosystems that have remained as they are, stable and not changing, right next to the niche so to speak, of kinds that have demonstrated the capability of filling that niche elsewhere,or that seem to be able to by all appearance. The hummingbird role, for example,in Asia. The ant role,in Hawaii. So we suspect that the plateauing of evolution in a successful species is not necessarily due to constraint alone, not maintained solely by selection and culling of the less fit, in all cases.
I was about to say, like what? Asia does have bats, moths, and birds that fill that roll, though I'm not sure how well. I guess the best way to see if a roll is being filled "well" is to introduce a species and see if they establish themselves and/or out compete all the native wildlife. We see this occurring all over the place with introduced species, of course. It may be too "expensive" for a species to slide into another niche that is already filled (if you believe in the niche, myself, I'm not so confident it exists). Something else may already be filling that space, and the mutations to move into that niche would be to costly. Transitory mutations would reduce fitness in its already existing niche, and of course be subpar in comparison to what's already occupying the niche. It's been shown that, with frogs, diversity correlates with the age of an ecosystem. It's been hypothesized that since tropical areas have remained habitable for the longest (since the last ice ages), they have greater diversity not because of more niche space, but simply longer time for things to diversify. In places without "saturated niches," there's room for introduced species. And since all time in all places have been finite, due to the vagaries of chance, not all niches will be perfectly filled. I think the issue can be resolved as a problem due to population subdivision, not a molecular one. As for Hawaii, the only bugs that could get out there were Dipterans. It was just too far out for other inects to get carried to. Ants never made it there. For the ant niche to be "filled" you needed to take the Diptera, something with hundreds of millions of years of preadaptations, and turn it into an ant in 82 million years. Nevermind that the first Hymenoptera showed up in the Triassic period, and had some 170 million years before Hawaii even showed up to perfect being antlike. In fact, there were many ground dwelling insects that had come from orders that one wouldn't associate with certain types of behavior, that radiated to fill the empty niches. However, they only had 80 some MY, while any introduced insects had the benefit of several hundred million years at filling that niche.
OK, the article was published in June, (unpublished, "quite different", non-authoritative and somewhat expanded version here: 0806.2331), and only after the press release does the ID marketing team respond. The press release has received plenty of criticism, from PZ Myers of ScienceBlogs and by T. Ryan Gregory of ScientificBlogging. The paper seems to be more of a pretty non-ground-breaking piece which is being written, reviewed, and published outside of the community of biologists so the language and perhaps the road to the press release is a bit tortured.
