at The University of Texas at Austin and Washington State University have seen
an increased reaction to stress in animals whose ancestors were exposed to an
environmental compound generations earlier, according to a press release
appearing on ScienceDaily.
findings, published in the latest Proceedings of the National Academy of
Sciences, put a new twist on the notions of nature and nurture, with broad
implications for how certain behavioral tendencies might be inherited.
researchers — David Crews at Texas , Michael Skinner at Washington State and
colleagues — exposed gestating female rats to vinclozolin, a popular fruit and
vegetable fungicide known to disrupt hormones and have effects across
generations of animals. The researchers then put the rats'' third generation of
offspring through a variety of behavioral tests and found they were more
anxious, more sensitive to stress, and had greater activity in stress-related
regions of the brain than descendants of unexposed rats.
are now in the third human generation since the start of the chemical
revolution, since humans have been exposed to these kinds of toxins," says
Crews. "This is the animal model of that."
ancestral exposure of your great grandmother alters your brain development to
then respond to stress differently," says Skinner. "We did not know a
stress response could be programmed by your ancestors'' environmental