Evolution
Medicine
An Evolutionary Explanation for Higher Rates of Birth by Caesarian Section?
Researchers writing in the Proceedings of the National Academy of Sciences contend that higher rates of babies being delivered by Caesarian section have an evolutionary explanation. The BBC reports:
Caesarean births ‘affecting human evolution’
The regular use of Caesarean sections is having an impact on human evolution, say scientists.
More mothers now need surgery to deliver a baby due to their narrow pelvis size, according to a study.
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.
Historically, these genes would not have been passed from mother to child as both would have died in labour.
Researchers in Austria say the trend is likely to continue, but not to the extent that non-surgical births will become obsolete.
Plausible, but if they’re right, it’s nothing more than microevolution. Douglas Axe, author of Undeniable: How Biology Confirms Our Intuition That Life Is Designed, tweets a point that the report doesn’t get into:
Long-standing evolutionary question: Why hasn’t human pelvis become wider? Human brain was a snap. Why not pelvis? https://t.co/hxZow9vOc9
— Douglas Axe (@DougAxe) December 7, 2016
Good question. What’s the answer?
@d_klinghoffer Yet another example of the stark contrast between natural selection of legend (all powerful) and the humble reality.
— Douglas Axe (@DougAxe) December 7, 2016
The legend of natural selection holds that unguided forces fundamentally generate and shape the most marvelous objects in biology, up to and including the human brain. Don’t believe every legend that you hear.
Photo credit: Robert Whitehead, [CC BY 2.0], via Wikimedia Commons.