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Author Topic:   Is Reproductive Success the Gold Standard?
Percy
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Posts: 22498
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.9


Message 4 of 20 (496939)
01-31-2009 4:38 PM
Reply to: Message 1 by lyx2no
01-31-2009 12:41 PM


While I wouldn't say what you said was wrong, because you mixed in some unscientific concepts it couldn't be considered correct, either. "Genetic perfection"? "Excessive neutral and beneficial genetic variation?" I think this is why RAZD tried to reexpress what you said without the pseudo-scientific mumbo-jumbo.
Probably what RAZD objected to most was the phrase "genetic perfection," which means that some genomes must be better than others. But the value of a genome is how well the organism is adapted to its environment. Obviously a species that's going extinct (these days usually because humans have destroyed its native habitat) does not possess a very successful genome for it's environment. And a species that has overpopulated its environment (like human beings) have a very successful genome, but not in all environments. Drop a person into the ocean off Antarctica in winter and see how well he competes with the penguins. Now who has the most perfect genome?
So we don't use the term "genetic perfection" - there's no such thing. The proper term is adaptation, and part of what ecologists study is how well or poorly adapted creatures are to their existing environment.
There's also no such thing as "excessive neutral or beneficial genes". First, you have a terminology problem, because there's no such thing as a neutral gene. A mutation to a gene can be harmful, neutral or beneficial. In other words, it can be worse, the same, or better than the gene it replaces. Genes themselves are not usually said to be neutral, though you've got the right concept. A gene might be inactive, or turned off, or just have no effect, but I don't think neutral is the correct term for that type of gene.
Second, if an organism is well adapted to its environment but 99% of its genes are junk DNA that have no effect, would you call that excessive? Maybe you'd call it inefficient, since each cell division requires copying the 99% useless portion, but now put it in the context of a changing environment, and suddenly that useless DNA serves as a resource for mutation to craft adaptations.
And if an organism is poorly adapted to its environment but 99% of its genes are beneficial (and 1% really harmful genes), would you call that excessive?
So you can't make judgments on whether genes are excessive are not. The criterion is degree of adaptation to the environment. Other criteria make no sense.
--Percy

This message is a reply to:
 Message 1 by lyx2no, posted 01-31-2009 12:41 PM lyx2no has replied

Replies to this message:
 Message 8 by lyx2no, posted 01-31-2009 6:20 PM Percy has not replied

  
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