Learn about how huge Megalodon was and why some people have misophonia, a severe hatred of sounds. Plus: a trivia game! Dive deeper into all your favorite Shark Week shows with Shark Week’s Daily Bite Podcast hosted by Luke Tipple: Listen on Apple Podcasts: https://podcasts.apple.com/us/podcast/shark-weeks-daily-bite/id1527053422 Listen on Spotify: https://open.spotify.com/show/0dfzM1ktSB1mSKD5z4Qujm?si=R8rNBksMRS-JrgMs9JIJ5g&dl_branch=1 Learn more: https://www.discovery.com/shark-week/everything-you-need-to-know-about-the-daily-bite-podcast Here's just how huge Megalodon was by Grant Currin Body size of the extinct Megalodon indeed off the charts in the shark world. (2020). EurekAlert! https://www.eurekalert.org/pub_releases/2020-10/tfg-bso092120.php Body, jaw, and dentition lengths of macrophagous lamniform sharks, and body size evolution in Lamniformes with special reference to “off-the-scale” gigantism of the megatooth shark, Otodus megalodon. (2020). Historical Biology. https://www.tandfonline.com/doi/full/10.1080/08912963.2020.1812598?scroll=top&needAccess=true Fletcher, T. (2021, January 11). Giant ancient sharks had enormous babies that ate their siblings in the womb. The Conversation. https://theconversation.com/giant-ancient-sharks-had-enormous-babies-that-ate-their-siblings-in-the-womb-152903 Baby Megalodons Were 6-Foot-Long Womb Cannibals, Study Suggests. (2021). The New York Times. https://www.nytimes.com/2021/01/10/science/megalodons-baby-shark.html Episodes referenced in Curiosity Challenge Trivia game: Skipping stones: https://omny.fm/shows/curiosity-daily/stress-during-pregnancy-might-affect-the-babys-sex-skipping-stones-overspending Bats: https://omny.fm/shows/curiosity-daily/bats-map-the-world-by-time-not-distance Things we overlook: https://omny.fm/shows/curiosity-daily/why-we-always-forget-that-less-is-more-leidy-klotz-subtract-the-untapped-science-of-less A severe hatred of sounds may come down to a sensitive brain connection by Kelsey Donk Supersensitive connection causes hatred of noises. (2021). EurekAlert! https://www.eurekalert.org/pub_releases/2021-05/nu-scc052421.php Kumar, S., Dheerendra, P., Erfanian, M., Benzaquén, E., Sedley, W., Gander, P. E., Lad, M., Bamiou, D. E., & Griffiths, T. D. (2021). The motor basis for misophonia. The Journal of Neuroscience, JN-RM-0261-21. https://doi.org/10.1523/jneurosci.0261-21.2021 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.
Learn about how huge Megalodon was and why some people have misophonia, a severe hatred of sounds. Plus: a trivia game!
Dive deeper into all your favorite Shark Week shows with Shark Week’s Daily Bite Podcast hosted by Luke Tipple:
Here's just how huge Megalodon was by Grant Currin
Episodes referenced in Curiosity Challenge Trivia game:
A severe hatred of sounds may come down to a sensitive brain connection by Kelsey Donk
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/why-megalodon-was-so-huge-misophonia-in-the-brain-trivia
CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from curiosity-dot-com. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, we’re wrapping up Shark Week by helping you learn about how huge Megalodon really was. Then, we’ll test your knowledge with this month’s edition of the Curiosity Challenge trivia game. You’ll also learn about what might cause some people to have a severe hatred of sounds.
CODY: Let’s satisfy some curiosity.
Megalodons are truly the darlings of Shark Week. These things are huge, mysterious, and... very much extinct. They could grow up to 50 feet or 15 meters long — way bigger than any other species of predatory shark. How’d they pull it off? New research suggests the secret may have been cannibalism. Of their siblings. While in the womb.
Megalodon went extinct about 3 million years ago. Researchers don’t know that much about them because they aren’t very well preserved in the fossil record. The main reason is that their bodies were made mostly of cartilage, not bone, which doesn’t preserve well. Luckily for us, some skeletal remains have survived. We’re talking teeth, skulls, and vertebrae, or bones of the spine. And because, like all sharks, Megalodon constantly lost and regrew its teeth, its massive, human-hand-sized chompers are one of the main sources of evidence researchers have used to determine the creature’s size.
But the new research into how the creatures managed to grow so large come from fossilized vertebrae. This one came from a Megalodon that lived about 15 million years ago whose remains were found in Belgium in the 1860s. Researchers think the shark in question died at 46 years old. They think that because sharks grow a new layer of tissue on their vertebrae each year, sort of like a tree. (You might remember we talked about that on a recent episode.) And that’s good news for researchers because it offers a reliable way to track an individual’s growth over the course of its life.
The scientists took what they knew about development in living sharks to interpret the growth rings. What they concluded is amazing: the shark was 2 meters, or 6 and a half feet, at birth. That means it was taller than most humans before it was even born! Including ME!
How could a fetal megalodon have grown so large? Researchers have previously guessed the ocean giants were warm-blooded, but the new evidence supports another theory. Maybe the first individuals to hatch inside the mother’s womb got a head start on life by feeding on their siblings. Here’s how it might have worked: sharks give birth to live young, but the babies do most of their development inside of eggs that hatch before birth. The vertebrae fossils the researchers studied tell the story of a megalodon that got a lot of high-quality protein very, very early in its life.
The idea that Megalodon grew so big because it ate its siblings in the womb might sound wild, but it’s actually not much of a surprise for shark scientists. That’s because living relatives of the megalodon do the same thing.
Siblings really are the worst.
It's time for the Curiosity Challenge! Every month, I call up a listener and put them to the test by asking them three questions about stories we ran on Curiosity Daily in the previous month. For this Curiosity Challenge, I talked to Fiifi in Accra, Ghana in West Africa. Have a listen!
Man, we've had a streak of perfect scores lately. I've gotta step up my game! How did YOU do? If you’d like to play next month, OR if you have a question you’d like us to answer on the show, shoot us an email at curiosity at discovery dot com, or leave us a voicemail at 312-596-5208!
Some people truly hate certain sounds. The sound of someone chewing gum or breathing loudly can send some people into a rage or make them flee the room. It’s called misophonia, and neuroscientists just discovered something surprising about how it works in the brain.
Misophonia is pretty common. Anywhere from 6 to 20 percent of people have some sounds they just can’t stand. Up until now, doctors and researchers have thought of it as a sound processing disorder.
But a new study suggests that it’s not just about sound processing. It may also come down to a super-sensitive connection between the brain’s hearing center and its motor region.
To come to this conclusion, researchers recruited participants with and without misophonia and played sounds for them while conducting brain scans. Some sounds were the participants’ “trigger” sounds, others were neutral. The hearing centers in all of the participants’ brains responded to the sounds in about the same way, whether they had misophonia or not.
But researchers noticed a difference in how the motor control areas responded to sounds in people with misophonia. When they heard trigger sounds, there was strong communication between their brains’ hearing centers and the parts of the brain that control the movement of the face, mouth, and throat. That connection wasn’t activated when those people heard neutral sounds.
This connection is part of what scientists call the mirror system. We sometimes process other people’s actions by activating those parts of our own brains in a similar way. Our brains can help us understand other people’s behavior by showing us what that behavior feels like.
The theory is that people with misophonia have an involuntary overactivation of the mirror system when someone around them makes a trigger sound. That mirror system response is uncomfortable. It makes people feel like the sounds around them are intruding on their bodies, outside of their control.
To regain a sense of control, some people with misophonia find it helpful to mimic the action that causes the sound. So if you’re triggered by the sound of, say, chewing gum, it might help to also make a chewing movement with your mouth.
Interestingly, the researchers found similar supersensitivity between the visual and motor regions of the brain in people with misophonia. That led them to conclude that misophonia could be visual as well as auditory.
This research could bring a shift to therapies for misophonia. Lots of the existing treatments focus on sound and sound processing. In the future, they could also incorporate the visual and motor parts of the brain.
ASHLEY: We’re gonna recap what we learned today, but first, I want to remind you that you can do us a HUGE favor by voting for Curiosity Daily in the 2021 Podcast Awards! Visit podcast-awards-dot-com, register your email address, and find us in the drop-down menus for the categories of Education and Science & Medicine. That’s all you have to do! Voting in all other categories is optional!
CODY: And when you vote, you can also volunteer to be a judge to help select winners once finalists are announced in August, and that’ll give you an extra chance to vote for our show. So take a minute this weekend to visit podcast-awards-dot-com; we’ll also include this info — and a link — in today’s show notes. For now, here’s a sneak peek at what you’ll hear next week on Curiosity Daily.
ASHLEY: Next week, you’ll learn about how you can extract DNA from strawberries in your kitchen;
A surprising way shopping online can keep you healthier;
How to combat “revenge bedtime procrastination”;
Why pineapples eat you back;
And more! Okay, so now, let’s recap what we learned today.
[ad lib optional]
ASHLEY: Today’s writers were Grant Currin and Kelsey Donk.
CODY: Our managing editor is Ashley Hamer.
ASHLEY: Our producer and audio editor is Cody Gough.
CODY: Have a great weekend! [AD LIB SOMETHING FUNNY] Then, join us again Monday to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!