Deterministic Evolution

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Timshel

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http://newswatch.nationalgeographic...-different-islands-produces-similar-outcomes/


For years, evolutionary biologists have debated the predictability of evolution. Stephen Jay Gould famously said that if the tape of life could be rewound to the same starting point, it would replay with a very different outcome. On the other hand, many evolutionary biologists have pointed to the ubiquity of adaptive convergent evolution–when species facing similar environmental pressures evolve in highly similar ways–as evidence that evolution is deterministic.


A particularly interesting example of repeated convergent evolution occurs when two groups evolving in different places diversify to produce similar sets of descendant species. The existence of such “replicated adaptive radiations” would seem to be strong evidence for evolutionary determinism. For example, the cichlid fishes of the African Rift lakes have become an iconic textbook example, illustrated by diagrams matching up pairs of species from two lakes that are morphologically convergent (see figure on right). The problem is that there are hundreds of fish species in each lake—the example illustrates a number of cases of convergent evolution between the lakes, but does not demonstrate that the lake radiations themselves are overall more similar than one might expect; another possibility is that there are some cases of convergence embedded in a larger pool of non-convergent evolution.
 
Professor Baxter said:
http://newswatch.nationalgeographic...-different-islands-produces-similar-outcomes/


For years, evolutionary biologists have debated the predictability of evolution. Stephen Jay Gould famously said that if the tape of life could be rewound to the same starting point, it would replay with a very different outcome. On the other hand, many evolutionary biologists have pointed to the ubiquity of adaptive convergent evolution–when species facing similar environmental pressures evolve in highly similar ways–as evidence that evolution is deterministic.


A particularly interesting example of repeated convergent evolution occurs when two groups evolving in different places diversify to produce similar sets of descendant species. The existence of such “replicated adaptive radiations” would seem to be strong evidence for evolutionary determinism. For example, the cichlid fishes of the African Rift lakes have become an iconic textbook example, illustrated by diagrams matching up pairs of species from two lakes that are morphologically convergent (see figure on right). The problem is that there are hundreds of fish species in each lake—the example illustrates a number of cases of convergent evolution between the lakes, but does not demonstrate that the lake radiations themselves are overall more similar than one might expect; another possibility is that there are some cases of convergence embedded in a larger pool of non-convergent evolution.
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Fascinating!
 
Professor Baxter said:
http://newswatch.nationalgeographic...-different-islands-produces-similar-outcomes/


For years, evolutionary biologists have debated the predictability of evolution. Stephen Jay Gould famously said that if the tape of life could be rewound to the same starting point, it would replay with a very different outcome. On the other hand, many evolutionary biologists have pointed to the ubiquity of adaptive convergent evolution–when species facing similar environmental pressures evolve in highly similar ways–as evidence that evolution is deterministic.


A particularly interesting example of repeated convergent evolution occurs when two groups evolving in different places diversify to produce similar sets of descendant species. The existence of such “replicated adaptive radiations” would seem to be strong evidence for evolutionary determinism. For example, the cichlid fishes of the African Rift lakes have become an iconic textbook example, illustrated by diagrams matching up pairs of species from two lakes that are morphologically convergent (see figure on right). The problem is that there are hundreds of fish species in each lake—the example illustrates a number of cases of convergent evolution between the lakes, but does not demonstrate that the lake radiations themselves are overall more similar than one might expect; another possibility is that there are some cases of convergence embedded in a larger pool of non-convergent evolution.
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I watched a documentary on the BBC a while back about the incredible variety of chichlids in Lake Malawi, Lake Victoria and Lake Tanganyika.
 
At least one school that studies cultural evolution has always asserted that human beings got to be the way we are because of our ability to utilize tools (thanks in large part to our having thumbs).
 
Threedee said:
At least one school that studies cultural evolution has always asserted that human beings got to be the way we are because of our ability to utilize tools (thanks in large part to our having thumbs).
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Well, lots of animals have thumbs and / or can use tools. Our fully opposable thumbs and erect gait gives us more capacity to use tools.
 
Professor Baxter said:
Yeah, it blows a hole in the idea that evolution is sheer random chance.
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No one believes it to be random chance. If that were so, it would not be "the theory of evolution", but "the theory of sheer random chance". Evolution could, indeed, produce wildly different results given the same starting point, and that would not, in any way, imply that it's "sheer random chance". That would merely point out that things are complicated and interesting. What a boring world it'd be if everything were predictable.
 
Panda Hugger said:
No one believes it to be random chance. If that were so, it would not be "the theory of evolution", but "the theory of sheer random chance". Evolution could, indeed, produce wildly different results given the same starting point, and that would not, in any way, imply that it's "sheer random chance". That would merely point out that things are complicated and interesting. What a boring world it'd be if everything were predictable.
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Of course, no person that should be taken seriously would claim it is "sheer random chance." Gould did not. But idiots like pmp or Ray Comfort often argue that evolution presents such ideas and they take statements by Gould and others out of context to support their strawman arguments.

Honestly, I don't think this says much about Gould's assertion, but it does say something about the way it is misused.

PostmodernProphet said:
lol....no evolution is NOT "caused".....evolution is sheer random chance.....
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Steelplate said:
Chicken/egg.....again.
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No not really. Deterministic evolution implies that similiar environmental conditions favor similiar species evolving in highly similiar ways. That's a different concept that deterministic biology in which environmental factors are discounted in genetic expresion.
 
Panda Hugger said:
No one believes it to be random chance. If that were so, it would not be "the theory of evolution", but "the theory of sheer random chance". Evolution could, indeed, produce wildly different results given the same starting point, and that would not, in any way, imply that it's "sheer random chance". That would merely point out that things are complicated and interesting. What a boring world it'd be if everything were predictable.
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That's an ecellent point WM and Darwin himself drew that very conclusion himself in The Origins of Species.
 
I think the article is intersting in that it does show that under a specific, very specific set of circumstances biological evolution could be deterministic, however, on the whole the evidence indicates that it is more stochastic in nature than deterministic.
 
Professor Baxter said:
Of course, no person that should be taken seriously would claim it is "sheer random chance." Gould did not. But idiots like pmp or Ray Comfort often argue that evolution presents such ideas and they take statements by Gould and others out of context to support their strawman arguments.

Honestly, I don't think this says much about Gould's assertion, but it does say something about the way it is misused.
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In always looking for an opportunity to be a dick.
 
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