Washington, Nov 30 (IANS) Researchers have found that women tend to shy away from their fathers during ovulation.
They have based their study on cell phone records of 48 women aged between 18 and 22 years, or near the height of a woman's reproductive years.
'Women call their dads less frequently on these high-fertility days and they hang up with them sooner if their dads initiate a call,' said Martie Haselton.
The research was conducted in the lab of Haselton, an associate professor of communication at University of California, Los Angeles.
Researchers suggest the behaviour may be motivated by an unconscious motive to avoid male control at a time when the women are most fertile, reports the journal Psychological Science.
But a more primal impulse may be at work - an evolutionary adaptation to avoid inbreeding, according to a statement by the university.
'Evolutionary biologists have found that females in other species avoid social interactions with male kin during periods of high fertility,' said Debra Lieberman, University of Miami assistant professor of psychology, who led the study.
'The behaviour has long been explained as a means of avoiding inbreeding and the negative consequences associated with it.'
The study builds on a mounting body of evidence of subtle and significant ways in which women's behaviour is unconsciously affected by the approach and achievement of ovulation.
For instance, women are more attracted during high-fertility periods to men whose physique and behaviour are consistent with virility, especially if they're single. They also tend to dress more attractively.
However, researchers found that women actually increased their phone calls to their mothers during this period of their cycle, and that this pattern was strongest for women who felt emotionally closer to their moms.
At high fertility, women proved to be four times as likely to call their mothers as they were to phone their fathers, a difference that did not exist during the low fertility days.