A new research has revealed that men become extremely jealous of other more masculine males, when their female partners are ovulating.
Previous studies have found that women's preferences for male physical appearance vary according to their fertility status. During ovulation women tend to find masculine looking men more attractive and prefer their voices and odour.
During this fertile phase women are more likely to have an affair with a masculine-looking man, as their features are linked to high testosterone levels, demonstrating good genetic qualities that can be passed on to offspring.
A new research at the Liverpool University has found that men sense this preference shift in their female partners and find masculine men more threatening during their partner's most fertile phase.
Rob Burriss and Dr Anthony Little, from the University's School of Biological Sciences, also found that men only behave in this way if their female partner does not use oral contraception – and is therefore more fertile.
Rob Burriss, from the University's School of Biological Sciences, explains: "'Groups of animals, such as chimpanzees, can live quite happily together, but when a female is ready to mate the two dominant males within the group become rivals and fight for her attention.
Similarly in humans, rated dominance increases when the female is most fertile. What is interesting here is that male behaviour is determined by that of the females; men become more wary of masculine-looking men only when the females facial preferences begin to shift prior to ovulation.
{{/usCountry}}Similarly in humans, rated dominance increases when the female is most fertile. What is interesting here is that male behaviour is determined by that of the females; men become more wary of masculine-looking men only when the females facial preferences begin to shift prior to ovulation.
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