A recent study used an MRI to monitor brain activity in males and females when they were exposed to a certain compound, HEX. The study determined that when males were exposed to HEX, brain activity was 20% less aggressive compared to the control while females were 13% more aggressive. In addition, they found that HEX boosted communication in the brain between areas that control aggression in men while in women it did the opposite (Science, 2021).
What could be the cause of this difference in reactions based on sex? Well, the study found that mammal mothers are more likely to use aggression to defend their babies, while fathers are more likely to attack their offspring. HEX is usually found on the top of babies’ heads. However, the researchers note that it has not been proven that there is enough HEX on babies’ heads to affect behavior (NY Post 2021).
This is really interesting to me because it shows that some things we see as acquired such as aggressiveness in males may be genetic. I wonder if personalities as a whole are genetic or acquired?
Frishberg, Hannah. “Baby Smell Blocks Aggression in Men – but Triggers It in Women: Study.” New York Post, New York Post, 24 Nov. 2021, https://nypost.com/2021/11/24/baby-smell-blocks-aggression-in-men-but-triggers-it-in-women-study/.
Chemical Emitted by Babies Could Make Men More Docile … https://www.science.org/content/article/chemical-emitted-babies-could-make-men-more-docile-women-more-aggressive.
Evolutionary Anthropology 