Bear Wild
Well-Known Member
Sexual selection – non-random evolution
Evolution theory is too often presented as a simplistic random mutation followed by natural selection where only the fittest survive conjuring the image of the strongest, best hidden, fastest, or other best characteristic for pure survival. Sexual selection as seen in birds gives a much different view. Yes, there are still mutations that at random can create new characteristics that can be exploited but the selection pressure would seem to be often in direct opposition of the image of survival of the “fittest”.
Ironically this was recognized by Darwin himself.
“I can see no good reason to doubt that female birds, by selecting, during thousands of generations, the most melodious or beautiful males, according to their standard of beauty, might produce a marked effect.” From the Origin of Species.
“He who admits the principle of sexual selection will be led to the remarkable conclusion that the cerebral system not only regulates most of the existing functions of the body, but has indirectly influenced progressive development of various bodily structures and of certain mental qualities. Courage, pugnacity, perseverance, strength and size of body, weapons of all kinds, musical organs, both vocal and instrumental, bright colours, stripes, and marks, and ornamental appendages, have all been indirectly gained by one sex or the other, through the influence of love and jealousy, through the appreciation of the beautiful in sound, colour, or form, and through the exertion of choice; and these powers of the mind manifestly depend on the development of the cerebral system” from the Descent of man
This form of selection has created amazing evolutionary changes in the male that appear can only be seen as placing them at a greater risk for predation with no advantage in helping with acquiring food and contrary the common view of natural selection.
Ironically during this time there was opposition to Darwin’s view of natural selection. George Wallace (who proposed evolution about the same time as Darwin) was against Darwin’s views of sexual selection in reference to coloration, ornamentation and behavioral pattern arguing that they did not represent a selection process but rather . (1889 book, Darwinism): "The enormously lengthened plumes of the birds of paradise and the peacock... have been developed to so great an extent [because] there is a surplus of strength, vitality and growth-power which is able to expand itself in this way without injury." “…the unselected side effects of an exuberant animal physiology that has a natural predilection for bright colors and loud song”
Kaar Groos also objected that the female could not have anything to do with male attributes. “This thought at once throws light on the peculiar hereditary arts of courtship, especially on the indulgence in flying, dancing, or singing by a whole flock at once. But the hindrance to the sexual function that is most efficacious, though hitherto unappreciated, is the instinctive coyness of the female. This it is that necessitates all the arts of courtship, and the probability is that seldom or never does the female exert any choice. She is not awarder of the prize, but rather a hunted creature. So, just as the beast of prey has special instincts for finding his prey, the ardent male must have special instincts for subduing feminine reluctance….”
Thankfully these views of male dominance in our societies are finally dying out and the recognition animals have complex cognitive abilities not so different from humans that allows for sexual selection.
And thus you have the birds of paradise project from the Cornell Ornithology laboratory.
Evolution theory is too often presented as a simplistic random mutation followed by natural selection where only the fittest survive conjuring the image of the strongest, best hidden, fastest, or other best characteristic for pure survival. Sexual selection as seen in birds gives a much different view. Yes, there are still mutations that at random can create new characteristics that can be exploited but the selection pressure would seem to be often in direct opposition of the image of survival of the “fittest”.
Ironically this was recognized by Darwin himself.
“I can see no good reason to doubt that female birds, by selecting, during thousands of generations, the most melodious or beautiful males, according to their standard of beauty, might produce a marked effect.” From the Origin of Species.
“He who admits the principle of sexual selection will be led to the remarkable conclusion that the cerebral system not only regulates most of the existing functions of the body, but has indirectly influenced progressive development of various bodily structures and of certain mental qualities. Courage, pugnacity, perseverance, strength and size of body, weapons of all kinds, musical organs, both vocal and instrumental, bright colours, stripes, and marks, and ornamental appendages, have all been indirectly gained by one sex or the other, through the influence of love and jealousy, through the appreciation of the beautiful in sound, colour, or form, and through the exertion of choice; and these powers of the mind manifestly depend on the development of the cerebral system” from the Descent of man
This form of selection has created amazing evolutionary changes in the male that appear can only be seen as placing them at a greater risk for predation with no advantage in helping with acquiring food and contrary the common view of natural selection.
Ironically during this time there was opposition to Darwin’s view of natural selection. George Wallace (who proposed evolution about the same time as Darwin) was against Darwin’s views of sexual selection in reference to coloration, ornamentation and behavioral pattern arguing that they did not represent a selection process but rather . (1889 book, Darwinism): "The enormously lengthened plumes of the birds of paradise and the peacock... have been developed to so great an extent [because] there is a surplus of strength, vitality and growth-power which is able to expand itself in this way without injury." “…the unselected side effects of an exuberant animal physiology that has a natural predilection for bright colors and loud song”
Kaar Groos also objected that the female could not have anything to do with male attributes. “This thought at once throws light on the peculiar hereditary arts of courtship, especially on the indulgence in flying, dancing, or singing by a whole flock at once. But the hindrance to the sexual function that is most efficacious, though hitherto unappreciated, is the instinctive coyness of the female. This it is that necessitates all the arts of courtship, and the probability is that seldom or never does the female exert any choice. She is not awarder of the prize, but rather a hunted creature. So, just as the beast of prey has special instincts for finding his prey, the ardent male must have special instincts for subduing feminine reluctance….”
Thankfully these views of male dominance in our societies are finally dying out and the recognition animals have complex cognitive abilities not so different from humans that allows for sexual selection.
And thus you have the birds of paradise project from the Cornell Ornithology laboratory.