Quote:
Originally Posted by questor
Moon, let me put it another way. How do you explain such diversity in fossil strata? If the animals in the layer were all exposed to a similar environment, why wouldn't they develop similar traits? Why would some eat meat and others grass? Why would some grow wings and others grow horns? Do their genes have some kind of signal mechanism that says.. I need wings, let's grow some?
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There are many ways to make a living on Earth. Organisms evolve to get the energy they need in any open ecological niche. If some aquatic organism is better at getting food near the surface and another faces extinction, perhaps the challenged organism will flatten out, and feed and find cover on the bottom. This is what evolved twice in the lineage of
rays/
skates and unrelated
flatfishes. This is an example of convergent evolution.
The rays flattened on the belly, but the flatfishes(like soles, halibut, and plaice) flatted by laying on one side. This has resulted in a very wasteful and imperfect design in flatfishes, where during development their face slowly moves to one side, with both eyes facing up. IT is worth mentioning that hese imperfections(such as the way
our eyes are wired backwards) are quite difficult to square with the belief in magical creation by a perfect designer, but quite in line with the idea of gradual evolution adapting organisms to immediate environments.
Quote:
Originally Posted by questor
By the way, can you give an example of a succesful mutation that can be heritable?
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Darwin's finches - Wikipedia, the free encyclopedia
The case of the Galapagos Finches has been documented extensively. Peter and Rosemary Grant followed them through several draughts and watched the environment change the frequencies of beak shape in the population. There is also a segment on the wiki page about the molecular basis of the change.
This is one of a great many examples that could be brought up.
