A long-term study of 27,224 mice over 26 years challenges a basic assumption of Neo-Darwinism. The assumption is that natural selection guides evolution by removing “unfit” individuals. Therefore individuals that are more fit survive to pass on their genes. The study involved white-footed mice (Peromyscus leucopus) in the wild.
Researchers identified mice with broken, missing, or deformed limbs, missing eyes, cataracts, and missing or mutilated tails. Evolution predicts that these unfit mice would be removed from a population, and the researchers set out to see how quickly that would happen. The data shows that the survival rate of the impaired mice was no different from that of mice who had no physical impairments.
For humans, this observation would be even more dramatic. That is because humans crippled for many years have lived long lives, supported by family members or group associates. That kind of support has never been observed in mice. Moreover, human history is full of terrible acts by racists and political leaders, such as Hitler, who viewed minor physical characteristics as justification for persecution and even execution of other humans.
The evidence is that physical impairments in the animal kingdom do not necessarily cause the demise of an individual. This challenges a basic assumption of Neo-Darwinism which, like uniformitarianism, is not supported by the evidence.
— John N. Clayton © 2021