MonkeyInaT34
Grand Rapist of The Cunny Union
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Runaway selection hypothesis, in biology, an explanation first proposed by English statistician R.A. Fisher in the 1930s to account for the rapid evolution of specific physical traits in male animals of certain species. Some traits—such as prominent plumage, elaborate courtship behaviours, or extreme body ornamentation—are so strongly preferred by females of certain species that they will mate only with those males possessing the strongest expression of the trait. In subsequent generations, male offspring are more likely to possess that physical trait, whereas female offspring are more likely to possess a preference for that trait in males. Over time, the species may be characterized by extreme sexual dimorphism.
Evidence supporting this hypothesis has been found in several species. One of the most dramatic examples is the African long-tailed widowbird (Euplectes progne); the male possesses an extraordinarily long tail. This feature can be explained by the females’ preference for males with the longest tails. This preference can be demonstrated experimentally by artificially elongating the tails of male widowbirds. Similarly, male European sedge warblers (Acrocephalus schoenobaenus) with the longest and most elaborate birdsongs are the first to acquire mates in the spring.
For better understanding, I will give an explanation using deer as an example:
Let's take a deer, this deer has bigger antlers than all the other deer, which is a preferred trait among the females of his species, thus he gets more mates, and reproduces more.
This deer's offspring inherit this trait, his male offspring are more likely to grow larger antlers. And his female offspring are more likely to select mates with larger antlers, eventually to a point where they will no longer select mates below their preferred baseline.
This leads to a feedback loop, where females continuously select for more extreme traits, so males with more extreme traits reproduce, thus creating more males with extreme traits, and females who select for those extreme traits.
Eventually this becomes detrimental to survival, because the traits become so extreme they are practically useless, it is no longer about selecting for what is utilitarian, but for what is appealing.





