Curiosity Daily

A New Stonehenge Discovery and Why Females Feel Colder

Episode Summary

Learn about a mysterious new archaeological discovery around Stonehenge; and why females feel colder in many species. More from world-renowned Stonehenge archeologist Susan Greaney: STONEHENGE: LAND OF THE DEAD’ Premieres Sunday, November 28 at 8 PM ET/PT on Science Channel: https://press.discovery.com/us/sci/programs/stonehenge-land-dead/  Start your free trial of discovery+ at https://discoveryplus.com/curiosity  Follow @SueGreaney on Twitter: https://twitter.com/SueGreaney  Academic page: https://www.cardiff.ac.uk/people/research-students/view/122326-susan-greaney  Females feel colder in many species -- scientists say it was an adaptation to keep the sexes separate by Grant Currin  A new study reveals the evolutionary reason why women feel colder than men. (2021, October 5). EurekAlert! https://www.eurekalert.org/news-releases/930578  ‌Magory Cohen, T., Kiat, Y., Sharon, H., Levin, E., & Algar, A. (2021). An alternative hypothesis for the evolution of sexual segregation in endotherms. Global Ecology and Biogeography. https://doi.org/10.1111/geb.13393  Follow Curiosity Daily on your favorite podcast app to learn something new every day withCody Gough andAshley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.

Episode Notes

Learn about a mysterious new archaeological discovery around Stonehenge; and why females feel colder in many species.

More from world-renowned Stonehenge archeologist Susan Greaney:

Females feel colder in many species -- scientists say it was an adaptation to keep the sexes separate by Grant Currin

Follow Curiosity Daily on your favorite podcast app to learn something new every day with Cody Gough and Ashley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.

 

Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/a-new-stonehenge-discovery-and-why-females-feel-colder

Episode Transcription

CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. I’m Cody Gough.

ASHLEY: And I’m Ashley Hamer. Today, world-renowned Stonehenge archeologist Susan Greaney will help you learn about a mysterious new discovery around one of the best-known prehistoric monuments in the world. You’ll also learn why females feel colder in many species. 

CODY: Let’s satisfy some curiosity.

Susan Greaney Stonehenge interview (Cody)

There are some pretty mysterious places in the world, but one of the most mysterious has got to be Stonehenge. It's a ring of massive vertical stones topped by horizontal ones, all of which were carted in from hundreds of kilometers away and have been worked to fit together like wood joints. It's located in Southern England and it's as old as the Pyramids of Giza. And we're not sure why it exists. But the mystery keeps getting weirder, as our guest today is about to explain. Susan Greaney is an archaeologist who works for English Heritage as a Senior Properties Historian, where she's been researching the ancient structures of England for more than 16 years. She's also featured in a new documentary on Science Channel that debuts next week — details on that in a few minutes. For our first question, we asked her what it's like to see Stonehenge in person.

[CLIP 6:13]

Move over Stonehenge — you're not the most important ancient site around. Again, that was Susan Greaney, an archaeologist who's featured in the new documentary on Science Channel, Stonehenge: Land of the Dead. You can watch it this Sunday, November 28, or catch it afterwards on discovery+. You can find a link for a FREE TRIAL of discovery+ in today’s show notes, or visit discovery-plus-dot-com-slash-curiosity.

Females feel colder in many species -- scientists say it was an adaptation to keep the sexes separate by Grant Currin (Ashley)

For decades, researchers have found that men are most comfortable at slightly lower temperatures than women, on average. But it turns out that this doesn’t just apply to humans. Biologists have spotted it in a lot of species. According to new research, the reason might lie deep in our warm-blooded physiology. 

For humans, disagreement over the quote-unquote “right” temperature usually plays out as conflict over who controls the thermostat. But for most non-human animals, warming up or cooling off means moving to a different place. That might explain why the animal kingdom is chock full of species that split up by sex outside of the breeding season. Take the alpine ibex, for example. Researchers have found that females typically stick to lower elevations, where it’s warmer, while males are nudged higher and higher as the day heats up. In Australia, male kangaroos are more likely than females to park it in the shade during the hottest part of the day. And on the island of Madagascar, female grey dwarf lemurs tend to huddle up in warmer spots while solitary males nest in cooler areas. 

What gives? 

The truth is that researchers aren’t sure. It could be that larger individuals with better-insulated bodies can deal with cooler temps. In a lot of species, those are usually the males. Or maybe it isn’t about temperature at all. Maybe higher latitudes are where the best resources are, so the faster, stronger males get there first. 

The researchers behind this new study have a different hypothesis. Maybe separation is the point. Keeping males and females separate most of the time might offer some evolutionary advantages, like reducing competition for food. It also could lower the risk of an aggressive male harming females or her babies. 

To know for sure, a few things would have to be true: females would still have to prefer warmer temps in species where they’re larger than the males, and temperature would have to be the deciding factor — not something like altitude or latitude. 

To test their hypothesis, the researchers turned to birds and bats, two species where females are often larger than males. They searched archives for records of 31 species detailing where males and females had been spotted over the last 40 years. Sure enough, they found that male birds and bats tend to hang out in cooler spots while females spend time in warmer places. And yes, air temperature was the most important variable — it mattered a lot more than altitude, latitude, or body size. That supports the idea that the difference might lie in how males and females perceive temperature. It could be that 75 and sunny feels warmer to males than females. 

So maybe we didn’t evolve to fight over the thermostat. Instead, maybe evolution just wants us to take a break from each other for a while.

RECAP

Let’s do a quick recap of what we learned today

  1. CODY: There’s a brand-new Stonehenge discovery! Archaeologists found a circuit of big pits that enclose an area about a mile across around Stonehenge. The pits aren’t like anything we’ve found before, so researchers don’t know why they’re there or what they were used for. There might be offerings or fires or burials down in the pits, and hopefully we’ll find out once we’ve had time to excavate them.
  2. ASHLEY: Stonehenge is part of what’s called a “monument complex,” meaning that there are a lot of other things around it, like burials and even other monuments. After archaeologists used radar, magnetometry, and other technology to find these circles, we learned that the complex might have been even more important than we thought. And Stonehenge itself may not have even been the “main event” — it just happens to be the last monument standing. 
  3. CODY: Humans aren’t the only species where female prefer warmer temps than males. But since other warm-blooded species don’t have thermostats, they settle the argument by moving to different locations. A new study suggests this is an evolutionary strategy to keep the sexes segregated, which can cut down on conflict outside of the breeding season.  

[ad lib optional] 

ASHLEY: The writer for today’s female species story was Grant Currin.

CODY: Our managing editor is Ashley Hamer, who was also an audio editor on today’s episode.

ASHLEY: Our producer and lead audio editor is Cody Gough.

CODY: [AD LIB SOMETHING FUNNY] Join us again tomorrow to learn something new in just a few minutes.

ASHLEY: And until then, stay curious!