Fatherhood depletes testosterone, study finds(latimes.com)
latimes.com
Fatherhood depletes testosterone, study finds
http://www.latimes.com/news/science/la-he-fathers-testosterone-20110910,0,241588.story
5 comments
How does one quantify jealousy? It seems such a measurement must be subjective, and highly-influenced by both your definition and by your environment.
edit: especially when there's an equally-rationalizable reason for women to have jealousy: to keep the man around as provider / protector while they're more incapacitated than usual. They're stuck either risking their child with another man (not an evolutionarily sound action), or preventing him from being tempted away by more fertile prospects.
edit: especially when there's an equally-rationalizable reason for women to have jealousy: to keep the man around as provider / protector while they're more incapacitated than usual. They're stuck either risking their child with another man (not an evolutionarily sound action), or preventing him from being tempted away by more fertile prospects.
The way the authors quantified it was by taking cross cultural surveys. Basically they surveyed men and women from various cultures about their attitudes around jealousy and determined that in all cultures they studied men appeared to be more affected by jealousy.
You are right that there is a rational reason why women should be jealous as well. But women have a more rational reason to forgive their mate, because it is far easier for a man to walk away from the relationship and thus the child.
You are right that there is a rational reason why women should be jealous as well. But women have a more rational reason to forgive their mate, because it is far easier for a man to walk away from the relationship and thus the child.
Gotta say - the whole breastfeeding-prevents-ovulation myth needs to be ended. I have two children 11 months apart, a third a year and a half after the second. All of my children were breastfed - and it didn't stop ovulation.
I should have said that it tends to inhibit ovulation. I don't believe it's a myth though. It's just not a perfect mechanism.
I would like to know if the reverse effect can be produced on women. Can women produce more testosterone in situations that would generally be considered more masculine? There seemed to be a very significant finding for men who just had newborns, perhaps it is triggered more by a major life event rather than specifically becoming a parent. For instance, does getting married reduce testosterone? Does losing a love one reduce it? Does moving to a new home? Makes for an interesting article and find(?) but I don't think it can be significant until it can be concluded that parenting specifically reduces that hormone.
I had to do a double take this wasn't an Onion article. How on earth can the body "know" whether one has become a father? Turns out the term "fatherhood" is misleading or at least ambiguous. As the Hadza vs the Datoga example shows, it's not the act of inseminating a female that causes testosterone depletion but the lifestyle changes often (but not always) associated with fatherhood.
You know, I can pretty safely say that fatherhood depletes everything.
There are several chapters about the hormonal effects of childbearing and what the evolutionary benefits are for the children. A few i can remember off the top of my head are:
Breastfeeding will often prevent women from ovulating and thus becoming pregnant. In this way mothers resources are not strained by taking care of too many children at a time and the current child will have a better chance of survival.
Fetuses secrete a hormone called human placental lactogen that inhibits maternal insulin, this leads to high glucose levels in the blood and thus more nutrients available to the fetus it can also result in diabetes in the mother during the pregnancy.
preeclampsia (gestational high blood pressure) is another similar effect where hormones excreted by the fetus raise maternal blood pressure in order to increase blood flow to the placenta.
Having a fathers testosterone levels fall during early parenting is probably a key evolutionary adaptation because it would prevent fathers from seeking new mates (in order to make more babies and thus spread their genes) in order to care for the new child. The study noted that testosterone levels later rose when the children became older, this too follows the evolutionary argument because once a child is old enough it is more efficient for the father to attempt to father more children.
By far the most interesting part of this section in the book was about male jealousy. The theory is that because it is fairly difficult for a man to tell whether or not he is raising another mans child. men have evolved to be overly protective of their chosen mates so that they do not invest to many resources (time included) and thus lower their own genetic viability. Jealousy, while present in both sexes is a much stronger emotion in men (according to the authors this is true across all cultures).