Cesarean Births Could Be Affecting Human Evolution, Study Says (bbc.com)

CanadianRealist writes: Larger babies delivered by cesarean section may be affecting human evolution. Researchers estimate cases where the baby cannot fit down the birth canal have increased from 30 in 1,000 in the 1960s to 36 in 1,000 births today, [according to estimates from researchers at the University of Vienna in Austria.] Science Alert reports: "In the past, larger babies and mothers with narrow pelvis sizes might both have died in labour. Thanks to C-sections, that's now a lot less likely, but it also means that those 'at risk' genes from mothers with narrow pelvises are being carried into future generations. More detailed studies would be required to actually confirm the link between C-sections and evolution, as all we have now is a hypothesis based on the birth data." Agreed, more studies required part. Cesareans may simply be becoming more common with "too large" defined as cesarean seems like a better idea. It's reasonable to pose the question based simply on an understanding of evolution. Like it's reasonable to conjecture that length of human pregnancy is a compromise between further development in utero, and chance of mother and baby surviving the delivery.

Comments

Re:De-evolution

[Anonymous Coward]

Properly speaking, there is no such thing as de-evolution. Evolutionary pressure optimizes for survival in some particular environment, and nothing more. In this case, the particular environment is changing to one that includes medical science, so certain types of genetic specialization is no longer needed. People don't de-evolve more than bacteria de-evolve when they lose antibiotic resistance due to a lack of antibiotics :)

Re: This is why we need Trump

[bev_tech_rob]

I hope Trump gets rid of vaccinations while he's in office. These diseases are here to help rid our gene pool of bad genes, yet we keep trying to save those less fit. It only hurts our species in the long run!

We need NATURAL selection.

Jenny McCarthy is right -- even if for the wrong reasons.

Good deal. At the next Ebola outbreak, hop on a jet over to that location and help bury the bodies, but you can't wear any protective gear. If you have 'superior' genes, you should be fine, right?

Jerkwad...