When she sang “Cause you’re hot then you’re cold” it seems pop singer Katy Perry had it right. Men and women are hot and cold about each other. And not only is it natural, it’s part of evolution’s plan to keep us apart when we need to be and ensure the survival of the species.
Israeli researchers think they may finally be able to answer a question that has puzzled humanity for thousands of years: why do women feel the cold more than men?
The answer to that question, which has caused a myriad of arguments over air conditioner and heating controllers across the globe, has been debated by scientists for decades but now we may be closing in on a solution: evolution.
Scientists from Tel Aviv University investigating the behaviour of birds and bats in Israel reviewed research material that stretches back more than four decades and what they noticed was that birds and bats also exhibited differences in behaviour connected to temperature, just as men and women do.
What they have come up with is a theory that goes a long way to explaining the hot-cold relationship men and women have with temperature. And, it seems, it’s all about survival of the species.
“We suggest that the different temperature preferences reflect differences in the nervous system and that just as males and females feel pain differently, they experience hot and cold differently,” says the study’s lead author Dr Eran Levin of Tel Aviv University’s School of Zoology.
“As a result, they often stay apart from each other, seeking different temperatures. It’s most common among birds and bats. For example, you tend to find male bats go the higher altitudes at the top of a mountain while the females are in the valleys where the temperature is higher.
“Lots has been written about males and females in various species living separately, but the explanations varied from species to species. We have observed a clear pattern among birds and bats, explaining this by temperatures, and among mice, males live in colder places than females. Our theory suggests that these and other species perceive temperature differently guided by natural selection.”
Levin, who collaborated with researchers at the University of Haifa and Sourasky Tel Aviv Medical Center, says that this evolutionary pattern has proven to be very beneficial over millennia.
“This is because, with birds and bats, it causes genders to be separated outside breeding season, which reduces competition between males over females,” he says. “It reduces aggression caused by competition for females between males and reduces aggression toward females and their children.”
However, there is another big advantage in females feeling the cold more, he says. It’s usually females who care for offspring because in many cases the young need temperatures to be regulated for them. When females are more sensitive to cold, they are prompted more to warm the young.
Levin’s colleague Dr Tali Magory Cohen said that the evolutionary push was the same in humans — to give men and women space from one another.
“The bottom line is, going back to the human realm, we can say that this difference in thermal sensation did not come about so that we could argue with our partners over the air conditioning, but rather the opposite,” she says.
“It is meant to make the couple take some distance from each other so that each individual can enjoy some peace and quiet.
“The phenomenon can also be linked to sociological phenomena observed in many animals and even in humans, in a mixed environment of females and males: females tend to have much more physical contact between themselves, whereas males maintain more distance and shy away from contact with each other.”