Sexual Selection on a Full Planet...
Summary: Mating success is a key behavioral driver in the natural world, and for a good reason. Typically, more males survive to reproductive age than are needed to fertilize the next generation. Charles Darwin once summarized what is now known as ‘sexual selection’ as the effects of the “ struggle between the individuals of one sex, generally the males, for the possession of the other sex. ” 29 Sexual selection is the “tie - breaking” contest which establishes which genome contributes to the next generation. Sexual selection can occur both between males (intrasexual selection, such as white-tail bucks fighting for dominance) and by females (intersexual selection, where e.g. the female chooses to mate with a male, such as female peafowl choosing the peacock with the largest and most beautiful tail-fan with which to mate) 30 . But how to determine which male (or female) is likely to have more “fitness” in the current context? Biologists have shown that historically, the primary way to reliably demonstrate one's 'quality' during courtship is to display a “high - cost signal”— e.g. a heavy and colorful peacock's tail, an energy-expending bird-song concert, or a $100,000 sports car. Only these costly and hard-to-fake "handicap" signals are evolutionarily stable indicators of their producer's quality because cheap signals are too easy for low-quality imitators to fake. These handicaps signal the ability to acquire energy over and above what is necessary for the male’s own life processes, and to survive predation and competition pressures more intense than would be incurred without such handicaps 31 . In this sense 'waste' has been evolutionarily selected for! Think of the three drawbacks to a male peacock of growing such a hugely ornate tail: 1) the extra energy, and nutrients needed
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