I’ve said this many times that ideas about evolution via selection of individuals or groups. I’ve referenced genes that can harm males but thrive in females such that some species of insect almost reach extinction, in humans such sexually antagonistic genes probably cause hemochromotosis (beneficial till menstruation stops/in childhood but increases the death rates of middle aged men) but theres more extreme examples of gene selection I want to mention. Cuz i’m right.
That is some genes compete to get into a sperm/egg even at the detriment to their carriers. The T-locus gene in mice, 2 copies of the abnormal allele is fatal to males, males with just one copy transmit it to 90% of their offspring opposed to the regular 50% The genes actions benefit itself but harms the individual and species through continued propagation.
In humans polycystic ovaries (responsible for 21% of visits to infertility clinics) is characterized by menstrual irregularities, obesity and masculination. Studies have found that 80.5% of the sisters of women with polycystic ovaries are also effected. A rate too high to be explained through auto-sominal dominant or X linked gene. To date the most reasonable explaination offered is by William Hague and his colleagues who suggested that it may occur from transmission of DNA in the cytoplasm of the ovum or from genes which disort meiosis in ways that increase their own chances of getting into the egg, a process called meiotic drive.
Leave this in philosophy as its implications are more than scientific. Anyway more old reasons to discount group selection. (microorganisms also fit gene selection but theres more subtleties there)