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Overall the changes are good, but the removal of the point on natural selection is puzzling. [[User:Learn together|Learn together]] 18:14, 23 May 2007 (EDT)
Overall the changes are good, but the removal of the point on natural selection is puzzling. [[User:Learn together|Learn together]] 18:14, 23 May 2007 (EDT)
Sorry, I just felt it wasn't very encyclopedic the way it was worded especially the part in the form of the question. Also, it seems consistant with the Natural Selection that vestigial structures could be "in the process" of being phased out. [[User:GodWarrior|GodWarrior]] 18:26, 23 May 2007 (EDT)
Sorry, I just felt it wasn't very encyclopedic the way it was worded especially the part in the form of the question. Also, it seems consistent with the Natural Selection that vestigial structures could be "in the process" of being phased out. [[User:GodWarrior|GodWarrior]] 18:26, 23 May 2007 (EDT)
:Part of the 'two-edged sword' of natural selection is that it should weed out inefficiencies as an outgoing occurrence and if it's not doing so, then they aren't inefficiencies. Giving it an open ended "in the process" can be fine if we're talking about short time periods on an evolutionary scale, but when we're talking about tens of millions of years then there is a benefit or a neutrality to the structure that by definition says it is not useless. [[User:Learn together|Learn together]] 19:45, 23 May 2007 (EDT)
:Part of the 'two-edged sword' of natural selection is that it should weed out inefficiencies as an outgoing occurrence and if it's not doing so, then they aren't inefficiencies. Giving it an open ended "in the process" can be fine if we're talking about short time periods on an evolutionary scale, but when we're talking about tens of millions of years then there is a benefit or a neutrality to the structure that by definition says it is not useless. [[User:Learn together|Learn together]] 19:45, 23 May 2007 (EDT)
:::Structures with any meaningful size to them are never neutral if they perform no positive function. The body has to use resources to sustain them as part of the overall living organism. [[User:Learn together|Learn together]] 22:31, 24 May 2007 (EDT)
:::Structures with any meaningful size to them are never neutral if they perform no positive function. The body has to use resources to sustain them as part of the overall living organism. [[User:Learn together|Learn together]] 22:31, 24 May 2007 (EDT)
:::That is true. However, many vestigial structures are greatly reduced in size such as the coccyx and appendix such that their impact on resource usage is negligible in comparison to other factors, even random ones. This makes their impact on reproductive fitness essentially neutral. Consider the appendix, a thin piece of tissue about four inches long, the resources that go in to creating and maintaining such a structure are not likely to have any effect on the number of successful matings a person has. Also consider that the genes responsible for making a vestigial structure may be closely linked genetically (or even share some of the same genes) with the genes that are responsible for making other structures that are still required in humans. This could make it very difficult to remove the genes responsible for the vestigial structure without disturbing those that are still needed. [[User:GodWarrior|GodWarrior]] 09:50, 25 May 2007 (EDT)