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Old 03-02-2017, 07:09 AM
Haldurson Haldurson is offline
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Join Date: Oct 2013
Posts: 129
Quote:
Originally Posted by Irishman View Post
The traits that fit the environment get pushed by natural selection to improve, with the lesser versions disappearing by outcompetition.
Traits don't improve -- they either survive or they don't.

There are more complex traits that are controlled by multiple pieces of DNA, and that may be what you are thinking of. There are multiple traits that are linked to a propensity towards addiction, for example. There are multiple traits that are linked to a propensity to higher intelligence.

And some traits that give an advantage may also give a disadvantage. For example, the ability to breed more offspring may seem like an advantage in nature. But every niche has limited resources, and such an 'advantage', if it's too 'good' may actually drive that species towards extinction.

Furthermore, evolution can push creatures towards specialization to a given niche. Lots of fur and fat and so on is a real advantage in colder climates. But if things warm up, not so much. Sometimes less evolved creatures tend to be hardier and more resilient to changes in the environment. Again, it's not about perfection, it's about the ability to survive to breeding age within a given niche.

What's caused a lot of confusion is the misuse of the word evolution in non-scientific circles to be synonymous with "improvement". But that's not what it actually means in scientific terms. It's simply about surviving and breeding, and that doesn't always mean improving.