Transgendered “female” hormone admits guilt, breaks down in court. Knocked-out mice provided crucial evidence. Furious Testosterone files lawsuit for historical systemic martiarchal defamation of character.
EVANSTON, Ill. – In an unexpected discovery, Northwestern University scientists are the first to show that progesterone, a hormone associated with female reproduction and maternal behavior, plays a key role in regulating male aggression toward infants in mice. Testosterone, not progesterone, had been thought to be responsible.
The absence of progesterone reduced aggression while promoting positive paternal behavior.
“We discovered that the hormone progesterone and its receptor are important in males, not just females,” said Jon E. Levine, professor of neurobiology and physiology, who led the provocative study. “Paternal behavior may be based in the same biology as maternal behavior.”
Although hostile behavior had previously been attributed to testosterone, a correlation between testosterone and male behaviors directed at young *has never been established. *Seeking another explanation for the male behavior, Levine’s research team tested paternal behavior in progesterone receptor knockout mice. (These mice lack the gene that encodes progesterone receptors and thus the animals are not affected by the presence of progesterone.)