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Old 06-24-2016, 05:39 PM
TriPolar TriPolar is online now
Join Date: Oct 2007
Location: rhode island
Posts: 38,002
Originally Posted by Carl Pham View Post
Because they can. You're misunderstanding genetics. Natural variation through random mutation will generally cause individuals to have quite significantly varying features, particularly for such simple characteristics as size. What natural selection generally does is rein in these variations, when they compromise some aspect of function that impacts survivability and breeding success. Hence, features of our genome that are absolutely mission-critical, e.g. certain basic enzymes for respiration, are exceedingly well conserved. No one has the slightest variation in them. Similarly, the size, shape and structure of the heart or airway or spinal cord is very consistent, since nearly any experiment along different lines is promptly fatal. In short, what needs evolutionary explanation in terms of functionality is uniformity of features, not variation. Variation is natural. Uniformity is not.
Agreeing here. Breasts are uniquely human, that is the large amount of fat covering mammary glands is unique. That means this characteristic hasn't undergone the long term evolution of other human characteristics that are incrementally changed from our ancestors until reaching an equilibrium with function and survival.