TEL AVIV, Israel — Men and women have plenty of things they disagree on — and that often includes the climate. Researchers say the perception that women often feel colder than men is more than just myth — it may be an evolutionary fact. A team from Tel Aviv University’s School of Zoology add this isn’t just the case for humans, but for many other species as well.
So why do females prefer the heat while males are cranking up the air conditioning? The study finds there’s a real reason for this, and it’s to keep the genders further apart!
“We propose that males and females feel temperature differently. This is a built-in evolutionary difference between the heat-sensing systems of the two sexes, which is related, among other things, to the reproduction process and caring for offspring,” a team led by Dr. Eran Levin and Dr. Tali Magory Cohen writes in a media release.
Along with men and women battling over the thermostat, study authors looked at how this phenomenon also plays out among birds and bats. Levin notes that previous studies have found that the bat genders actually separate during the breeding season. Male bats head toward cooler areas during this time.
Other studies have also revealed similar behavior among birds and mammals, with males heading to cooler areas while females stay in warmer areas with their offspring. In fact, even among species where the genders live together, scientists find males often stand in the shade and females soak up the sun.
The team in Israel collected information over 40 years (from 1981 to 2018) on thousands of birds from 13 species which migrate each year. They also looked at 18 species of bats during the study.
Evolution says ‘think of the children!’
You might be asking, why focus on birds and bats? Researchers say these animals are highly mobile, especially migratory birds. With that in mind, the team suspected that this separation between the sexes — sometimes even spanning different climate zones around the globe — would make the study of gender temperature preferences very clear.
The study finds the reason evolution seems to be pushing males and females apart may be to keep their babies safe. Cohen adds that when evolution pushes males in cooler climates and females into warmer climates, it cuts down the competition over resources. It also keeps potentially aggressive males from endangering offspring.
“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: 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,” Cohen says.
“We have hypothesized that what we are dealing with is a difference between the females and males’ heat-sensing mechanisms, which developed over the course of evolution. This difference is similar in its essence to the known differences between the pain sensations experienced by the two sexes, and is impacted by differences in the neural mechanisms responsible for the sensation and also by hormonal differences between males and females,” Dr. Levin concludes.
The study appears in the Journal Global Ecology and Biogeography.