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Despite decades of public relations. From Chase Nelson at Inference Review:
Haldane, one of the founders (along with Ronald Fisher and Sewall Wright) of mathematical population genetics, was the first to quantify such a limit on the speed of adaptive evolution. He concluded that the cost of selection “defines one of the factors, perhaps the main one, determining the speed of evolution.” Cost was the main reason Motoo Kimura proposed the neutral theory of molecular evolution. Many others cite its importance.
Nelson’s point is that “In general, the number of individuals combining several specific characteristics decreases exponentially with each additional requirement.”
For one thing, the requirements must all work together in the same live body. For example, a beagle has an amazing sense of smell but is otherwise a stupid dog, relative to others, and would not last long in nature. It would get torn apart by a wolf, who — maybe with a lesser sense of smell — at least understands the importance of shutting up and moving surreptitiously, working with the pack, while hunting. But that, along with pack discipline in general, is an additional requirement for selection.
The implications for mammalian evolution were considered so severe that the issue became known as Haldane’s dilemma.
Despite Haldane’s work, a massive body of literature has accumulated asserting the primary role of natural selection in evolutionary change, often implying rates of adaptive evolution that exceed plausible limits. I maintain that cost, though often neglected in contemporary studies, remains as important as Haldane’s mathematical theory of selection. By setting a limit on the number of selective evolutionary changes, Haldane provided a simple way to test the plausibility of many evolutionary scenarios. More.
A growing number of biologists seeks a serious examination of this issue, as an alternative to Darwin pieties, and good luck to them.
See also: Has there really just not been enough time to observe Darwinian evolution at work?
Beagles hunting:
Remove earplugs. Meanwhile, wolves hunting (as always, with no human assistance):