He was born yesterday and the drama has already started.
A new study finds that the smell emitted by newborns causes an abrupt gender response.
According to research by scientists at the Weizmann Institute of Science in Israel, the man-made molecule hexahydrate (HEX) – found in large quantities on a child’s scalp – provokes aggression in women while inhibiting it in men. The results were Posted this month in the journal Science Advances.
“We’ve found that HEX does not have a perceptible smell, but when you smell it, it affects the way you behave toward others – specifically, your aggressive reactions to others,” said Dr. Eva Mishor, who led the study, He said in a press release.
To determine this, the researchers exposed about half of the 130 study participants to HEX while the rest received a control. Then they gave the test subjects the option of blasting one of the game partners with annoying noises of varying intensity. While women exposed to HEX consistently went for the loudest and most annoying sounds, men exposed to HEX consistently chose milder sounds than their non-HEX-exposed counterparts.
While perhaps a counterintuitive finding based on gender norms, Mishor asserted that sexual differentiation has an evolutionary explanation.
“Male aggression many times translates into aggression towards newborns; infanticide is a real phenomenon in the animal kingdom. At the same time, female aggression is usually translated into defense of offspring.” HEX appears to affect men in terms of having more social regulation, their aggressiveness was controlled and acted as a ‘calm’ cue for them, while in women regulation was decreased and could be seen as a ‘release’ signal.
The molecular brain response is, in a way, an evolutionary strategy for children to connect with their parents to increase their odds of survival. “Children cannot communicate through language, so chemical communication is very important to them,” said Professor Noam Sobel, whose research group led the study. “As a child, it is in your best interest to make your mother more aggressive and reduce your father’s aggressiveness.”
In addition to finding that HEX odor affects men differently than it does women, the study is “among the first” to demonstrate a direct link between the odor molecule and human behavior.