UCLA researchers publish landmark meta-analysis of sexual preferences at ovulation
If she loves you and then she loves you not, don’t blame the petals of that daisy. Blame evolution.
UCLA researchers analyzed dozens of published and unpublished studies on how women’s preferences for mates change throughout the menstrual cycle. Their findings suggest that ovulating women have evolved to prefer mates who display sexy traits – such as a masculine body type and facial features, dominant behavior and certain scents – but not traits typically desired in long-term mates. (more…)
Like humans, some song sparrows are more effusive than others, at least when it comes to defending their territories. New findings from the University of Washington show that consistent individual differences exist not only for how aggressive individual song sparrows are but also for how much they use their signals to communicate their aggressive intentions.
The findings, published online Dec. 4 in Proceedings of the Royal Society B, show that while many birds signal their intentions clearly, other “strong silent types” go immediately to aggressive behavior and ultimately attack without first signaling their intentions. (more…)
The threat of infants being killed by unrelated males is the key driver of monogamy in humans and other primates.
The study by academics from UCL, University of Manchester, University of Oxford and University of Auckland, is the first to reveal this evolutionary pathway for the emergence of pair living.
The team also found that following the emergence of monogamy males are more likely to care for their offspring. Where fathers care for young, not only can they protect infants from other males, but they can also share the burden of childcare. (more…)
Researchers at the University of Exeter found that older male burying beetles make better fathers than their younger counterparts.
The study found that mature males, who had little chance of reproducing again, invested more effort in both mating and in parental care than younger males.
The study, published in the journal Proceedings of the Royal Society of London – B, considered how the likelihood of paternity influenced the way that males cared for young. Older males were good fathers and looked after the young even when they were unsure whether the offspring were theirs. Younger males, who had a higher chance of reproducing again, tended to care less for offspring, particularly when they were uncertain of their paternity. (more…)
Animal Findings Suggest That Gender May Also Influence Chemical Exposure Risks for Humans
COLUMBIA, Mo. — Parents, teachers and psychologists know boys and girls behave differently. However, that difference isn’t taken into account by most methods used to assess the risk to children from chemical exposure, according to Cheryl Rosenfeld, associate professor of biomedical sciences in the University of Missouri’s Bond Life Sciences Center. A series of experiments by Rosenfeld studied the effects of prenatal exposure to bisphenol A (BPA) on later reproductive-associated behaviors using a socially and genetically monogamous rodent, the California mouse, which may better mirror most human societies than other rodents. (more…)
A protein known as Sp2 is key to the proper creation of neurons from stem cells, according to researchers at North Carolina State University. Understanding how this protein works could enable scientists to “program” stem cells for regeneration, which has implications for neural therapies.
Troy Ghashghaei and Jon Horowitz, both faculty in NC State’s Department of Molecular Biomedical Sciences and researchers in the Center for Comparative Medicine and Translational Research, wanted to know more about the function of Sp2, a cell cycle regulator that helps control how cells divide. Previous research from Horowitz had shown that too much Sp2 in skin-producing stem cells resulted in tumors in experimental mice. Excessive amounts of Sp2 prevented the stem cells from creating normal cell “offspring,” or skin cells. Instead, the stem cells just kept producing more stem cells, which led to tumor formation. (more…)
The MU study is not claiming that BPA is safe, but that the previous series of studies are not reproducible.
COLUMBIA, Mo. — Following a three-year study using more than 2,800 mice, a University of Missouri researcher was not able to replicate a series of previous studies by another research group investigating the controversial chemical BPA. The MU study is not claiming that BPA is safe, but that the previous series of studies are not reproducible. The MU study, published in the Proceedings of the National Academy of Sciences, also investigated an estrogenic compound found in plants, genistein, in the same three-year study.
“Our findings don’t say anything about the positive or negative effects of BPA or genistein,” said Cheryl Rosenfeld, associate professor of biomedical sciences in MU’s Bond Life Science Center. “Rather, our series of experiments did not detect the same findings as reported by another group on the potential developmental effects of BPA and genistein when exposure of young occurs in the womb.” (more…)
Women with stable but not-so-sexy mates become more distant, critical during periods of high fertility
Long after women have chosen Mr. Stable over Mr. Sexy, they struggle unconsciously with the decision, according to a new study by UCLA researchers who look at subtle changes in behavior during ovulation.
At their most fertile period, these women are less likely to feel close to their mates and more likely to find fault with them than women mated to more sexually desirable men, the research shows. (more…)
