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<blockquote data-quote="Celebrim" data-source="post: 6515460" data-attributes="member: 4937">I suppose not, but changes in the expressed phenotype aren't necessarily strictly speaking evolutionary changes.&nbsp;&nbsp; That sort of thing can occur through real world polymorphism were the same population interbreeding exhibits several distinctive characteristics that allow it to engage in a wider variety of behavior (see for example Darwin's Finches).&nbsp; Polymorphic European wolves are believed to be the root stock of the domestic dog, which in its modern form exhibits all sorts of different phenotypes from what is essential one genetic breeding pool.&nbsp; Simplifying, imagine a species where it has for each different physical trait - length of coat, length of leg, length of snout, etc. - a set of 16 or so genetic switches that can be set to 0-1.&nbsp; In an average dog about half of these will be toggled to one or the other producing average expressed traits.&nbsp;&nbsp; Any two dogs are unlikely to produce offspring with anything but average traits.&nbsp; But under population pressure (or selective breeding) the average successful breeder will tend to have more of one or the other depending what aids the individuals fitness.&nbsp; The result will be a population with a lower than average number of '0's or '1's in the control region while still being a member of its same species.&nbsp; In a natural setting, the same population could potentially even reverse the process when conditions changed as long as a reasonable amount of genetic diversity remained in the group.&nbsp;&nbsp; This isn't evolution in the sense we normally mean it of the descent of species - this is a sort of complex evolved ability to adapt.&nbsp; This and several other interesting features of the genetic code are evolved to allow genetic stability and diversification without the need to rely on the slow, random, and usually harmful process of mutation.&nbsp;&nbsp; In fact, there are even some features of the genetic code that are designed to encourage mutation in those same phentotype control regions while protecting regions that are responsible for things you don't want to evolve because changes here would almost certainly be fatal - like say basic metabolic processes - in a sort of pseudo-Lamarkianism.</blockquote>

[QUOTE="Celebrim, post: 6515460, member: 4937"] I suppose not, but changes in the expressed phenotype aren't necessarily strictly speaking evolutionary changes. That sort of thing can occur through real world polymorphism were the same population interbreeding exhibits several distinctive characteristics that allow it to engage in a wider variety of behavior (see for example Darwin's Finches). Polymorphic European wolves are believed to be the root stock of the domestic dog, which in its modern form exhibits all sorts of different phenotypes from what is essential one genetic breeding pool. Simplifying, imagine a species where it has for each different physical trait - length of coat, length of leg, length of snout, etc. - a set of 16 or so genetic switches that can be set to 0-1. In an average dog about half of these will be toggled to one or the other producing average expressed traits. Any two dogs are unlikely to produce offspring with anything but average traits. But under population pressure (or selective breeding) the average successful breeder will tend to have more of one or the other depending what aids the individuals fitness. The result will be a population with a lower than average number of '0's or '1's in the control region while still being a member of its same species. In a natural setting, the same population could potentially even reverse the process when conditions changed as long as a reasonable amount of genetic diversity remained in the group. This isn't evolution in the sense we normally mean it of the descent of species - this is a sort of complex evolved ability to adapt. This and several other interesting features of the genetic code are evolved to allow genetic stability and diversification without the need to rely on the slow, random, and usually harmful process of mutation. In fact, there are even some features of the genetic code that are designed to encourage mutation in those same phentotype control regions while protecting regions that are responsible for things you don't want to evolve because changes here would almost certainly be fatal - like say basic metabolic processes - in a sort of pseudo-Lamarkianism. [/QUOTE]

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