...we should be just fine in the (English-speaking) west then: to a first approximation, no-one can afford the US health services outside dire emergencies, while over in the UK they're busy "starving the beast" so they can privatise huge swathes of it.
i don’t think evolution works that fast; the only thing that fast would be something like selective breeding for dogs, but thats intentional; the type of evolution you’re talking about is more on the order of 10^6 years
Everyone always says this but I’ve never heard it from an actual evolutionary biologist. Some genes evolve faster than others; in fact, some genes have themselves evolved to be able to evolve faster.
Evolution is working every single generation. Dogs no more or less than humans or anything else.
Dogs were selected, but everything responds to environmental pressures. All the time. Natural ones no different than human-provided ones, right?
And humans have changed more in the last 50K years than in the 1M before that. Because of civilization I have to think. Anyway, off by 2 orders of magnitude there, for really significant changes.
i’m not saying the effect is zero; im saying the effect is clearly too small; there are obviously degrees to this. halving of overall hormone levels are surely not explained by a measly three generations of improved health care removing the selective pressure in favor of the survival of high-hormone humans
> Improvement of health services reduces selection pressure on reproductive fitness of population
Yes this is true. With all the C-section babies we have now, if we ever loss access to low cost surgical delivery care, we are going to have a spike in childbirth related deaths. But the male infertility crisis is rising faster than evolution can adapt here. There is something external involved.
The average human reproductive fitness level is not anywhere near bad enough for just a couple of generations to have such a profound effect on reproductive health.