In recent years, biologists have increasingly recognized that evolutionary change can occur rapidly when natural selection is strong; thus, real-time studies of evolution can be used to test classic evolutionary hypotheses directly. One such hypothesis is that negative interactions between closely related species can drive phenotypic divergence. Such divergence is thought to be ubiquitous, though well-documented cases are surprisingly rare. On small islands in Florida, we found that the lizard Anolis carolinensis moved to higher perches following invasion by Anolis sagrei and, in response, adaptively evolved larger toepads after only 20 generations. These results illustrate that interspecific interactions between closely related species can drive evolutionary change on observable time scales.
Science in the news.
Humans domesticating themselves. Ideas similar to Frost’s genetic pacification.
Competition for niche space can promote evolution.
One can speculate that this may apply to humans: negative interactions between different hominid subspecies (i.e., races) can promote evolution of particularly a native subspecies whose territory is invaded by a related subspecies. The Third World invasion of the West may be stimulating rapid evolution of European human organisms. The question is: in what direction? If the evolution has a “group selection” aspect, evolution may be in the direction of greater ethnocentrism. However, a purely individualist selective pressure may actually select for even less ethnocentrism than even the feeble degree exhibited by extant Europeans. Thus, on an individual level, short-term fitness may accrue by “throwing your race under the bus” so to speak, due to the massive incentivization of White dispossession described by KMacD at TOO. Whatever the case, Europeans are likely exposed to novel selective pressures due to the occupation of their territory by alien hominid forms.