Biological or "Phenotypic" Plasticity is an adaptive response that is many, many times faster than a species can adapt due to Mendelian inheritance and Darwinian selection.
Consider a set of identical twins who are separated at birth. One grows up in La Paz, Bolivia (elevation 12,000 feet above sea level) and the other grows up in the Dead Sea, Israel (elevation -1350 feet). The child who grew up in La Paz, even though both twins are genetically identical (or practically so), will have greater lung capacity, more red blood cells, a more efficient heart and other, more subtle differences in their cardio-vascular and pulmonary systems.
In a similar way, identical twins separated and who grew up in Miami, Florida and Minot, North Dakota would have physical differences which would impact their resistance to heat (on the first twin) and cold (the second twin).
Adults also exhibit plasticity although not nearly as much as children. We can increase the size of our hearts via exercise, for example but our ability to increase the size of our blood vessels is much more limited.
"Maternal dominated" traits
There are still some areas in agriculture where breeders insist that the maternal "genetics" matter far more than the paternal contribution. That seems like a dubious claim outside of processes mediated by the ribosomes/mitochondria.
Dubious, genetically speaking, but not dubious from perspective of in-utero stresses and how it might change the developing embryo or fetus.
It would be interesting...
It would be interesting to see how maternal blood cortisol (stress hormone) levels impact the behaviors of the offspring. From a Darwinian standpoint, it would be to the offspring's advantage to be more "reactive" and quicker to initiate fight-flight responses if the mother's environment was relatively high in hazard and less reactive and slower to initiate fight-flight if the mother's environment was more placid and stable.
While it would be unethical to perform this experiment on humans, it could be done with lab-rats. One population would be housed under human, not-overcrowded conditions. The other population could be subjected to percussive sound, crowding and random electric shocks. The stressed maternal population could be moved to a low-stress environment before giving birth, thus the baby rats would never be directly exposed to the stress.
I assume there is some scale to measure rat aggressiveness. Perform a Tukey End Count or use any other appropriate statistical tool to see if the two populations of progeny are different.
Implications
If there is a strong prenatal influence attributable to environmental stress on reactivity, aggression and attention span then it would be a very strong vote in favor of traditional marriage.
If there is a measurable, prenatal influence, then having serial baby-daddies and out-of-wedlock births is not a victimless activity. It impacts everybody who rides public transportation, everybody who experiences road-rage, everybody who shops at malls.
ERGO, policies that create disincentives to marriage are hostile to civil society...it just takes a while for the consequences to show up.
I recall 30ish years ago when rap music was starting to become mainstream, there was a cohort of the population, both black and white, that decried the advent of "thug-life culture" and other new found -isms that were being pushed and promoted (huh, where have we seen that before?) This group railed against the misogyny, the violence, criminality, and how it was all extolled as virtuous by the 'artists' publishing said 'music'. They said that things like this would have knock-on affects down the road as youth were raised in a different belief structure than previous generations.
ReplyDelete'Thats just crazy talk', 'racist!', 'ignorant bigot', and a few other terms were tossed around quite heartily by people against the opposition to this change in society.
More and more, I believe the tinfoil hat people first, and simply assume the media and government is lying and pushing their agenda. I have yet to be proven wrong since adopting this assumption 20+ years ago.
Funny, I recall THE EXACT SAME CONVERSATION about how extreme gun violence in video games and movies would warp kids minds and turn them into stone cold mass murderers.
DeletePshaw! Crazy conservative bible thumping nutjobs, I tells ya....
Then add serious street level drugs to the mix.
ReplyDeleteHappy Daz are here again (sarc).
Even in my little town in a quiet state we often have codes called for manpower to restrain the ER's latest meth-head.
Did you read Aesop's (at Raconteur Report blog) tattoo solution?
DeleteThe first time whack-job visitor to ER must consent to a single tatt on their forehead before "treatment". The first tatt is the letter "D".
The second letter is "N".
The third letter is "R".
Frequent fliers are the bane of the ER.
I recall a study done with rats many years ago where the rats were stressed by overcrowding, feeding reductions, noise, and other stressors to see what the effects would be. The rats became mean, cannibalistic, all the bad effects you can see in modern urban enviornments today. However, the pregnant rats were not removed from the experiment before birthing so the study you propose is still possible.
ReplyDeleteFriend who was a ER doc worked where one culture came in with the 'horrible' back pain to get their dose of 'legal' pain drugs. When he wouldn't comply it was I'm gonna call Jackson, Sharpton or whoever was in power at that time. So he had business cards make up with his name, # and on the back was the number for Jackson, Sharpton. Handed them out like candy and the number coming into that ER went down. All he said was he never got a call.
ReplyDeleteThis is a very interesting idea. My ex was raised just as you posited. Every imaginable abuse was suffered by all the kids in her family. Probably even some unimaginable. I was raised more like Opie. It wasn't all roses and sunshine, but nothing even close to my ex. I could outline the character of the our marriage and kids but that would go very long. I think you may be on to something. It merits further study for sure.
ReplyDeleteOne other thing that 'transfers' from generation to generation is pain tolerance. Both my daughters got 'my' side of the family's high pain tolerance, much to their doctor's surprise.
ReplyDeleteGood thing! Isn't one of them paying taxes in California?
DeletePain thresholds is very specific to races/cultures.
DeleteBeen known for years....but we can't talk about those kind of things nowadays.
Just like certain disorders and afflictions are heavily concentrated in specific groups.
Old time docs had scads of little mnemonics (ie "fair, fat & forty"...Northern Europeans, espec women, over age 40 we're quite prone to gallbladder disorders)
Experiments on pregnant rats yce shown that increased stress on the female rats during fetal development led to a marked increase in homosexuality among the male rat offspring. MRI shows distinct structural differences between homosexual men and hetero men that is believe to be cause by chronic exposure to cortisol in utero. This would make homosexuality a "birth defect", not a choice.
ReplyDeleteWe can't do these tests on people, but we can look at history to see how people have handled (or not) difficult times.
ReplyDeleteFor example, China under Japanese occupation, Korean civilians during the Korean War, Romania in the 20 years before 1990.
Some of these people bounced back well, some didn't.
Look up mouse / rat heaven experiment. Research done by margret Sanger (founder of planned parenthood) research in to eugenics where she tracked down slaves breeding records.
ReplyDelete