Chemical cues from fathers may be delaying the onset of sexual
maturity in daughters, as part of an evolutionary strategy to
prevent inbreeding, according to researchers at Penn State.
"Biological fathers send out inhibitory chemical signals to
their daughters," said Robert Matchock, assistant professor of
psychology at Penn State's Altoona Campus. "In the absence of
these signals, girls tend to sexually mature earlier." The
effect of chemical cues on sexual maturity is common in the
animal world, Matchock explained. If the biological father is
removed from rodent families, the daughters tend to mature
faster, he said. "Recently, experts elsewhere discovered a
little-known pheromone receptor gene in the human olfactory
system, linking the role of pheromones on menarche, or the first
occurrence of menstruation," said Matchock, whose findings are
published in the recent issue of the American Journal of Human
Biology. Researchers, including Elizabeth Susman, the Jean
Phillips Shibley professor of biobehavioral h