Learn about the first animal scientists have ever discovered that doesn’t breathe oxygen; how we might be able to hijack the brain’s immune system to improve memory; and the biggest explosion in the history of the universe.
Learn about the first animal scientists have ever discovered that doesn’t breathe oxygen; how we might be able to hijack the brain’s immune system to improve memory; and the biggest explosion in the history of the universe.
Scientists discover first animal that doesn't breathe oxygen by Cameron Duke
We might be able to hijack the brain's immune system to improve memory by Grant Currin
Astronomers detect biggest explosion in the history of the universe by Grant Currin
Subscribe to Curiosity Daily to learn something new every day with Cody Gough and Ashley Hamer. You can also listen to our podcast as part of your Alexa Flash Briefing; Amazon smart speakers users, click/tap “enable” here: https://curiosity.im/podcast-flash-briefing
Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/first-animal-that-doesnt-breathe-oxygen-biggest-explosion-in-the-universes-history-and-improving-memory-with-the-brains-immune-system
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, you’ll learn about the first animal scientists have ever discovered that doesn’t breathe oxygen; how we might be able to hijack the brain’s immune system to improve memory; and the biggest explosion in the history of the universe.
CODY: Let’s satisfy some curiosity.
How long can you hold your breath? Well, however long that is, I guarantee that the parasite Henneguya salminicola [HEN-nuh-GOO-yuh SAL-mihn-nick-COAL-uh] has you beat: it doesn’t breathe at all. Yes, that’s right: scientists have discovered the first multicellular organism known to science that doesn’t breathe.
Here’s the scoop. H. salminicola is a distant cousin to jellyfish that makes its living by burying itself in the muscles of fish and underwater worms. It’s not a...nice parasite. It’s the cause of “tapioca disease,” a nasty infection that looks like a bunch of little white tapioca beads bursting from the fish’s skin. It reproduces by making little swimming spores that venture out to find and bury themselves in the tissues of other hosts. There’s not much oxygen to be had when you’re buried within muscle tissue, and that doesn’t bother H. salminicola one bit. This parasite doesn’t have to hold its breath when it dives in. It actually couldn’t breathe even if it wanted to.
The lack of breathing is weird because animals need oxygen to get energy from their food. Within animal cells, there are special structures called mitochondria that contain the genes that are responsible for respiration. H. salminicola doesn’t have any mitochondrial genes.
That means this parasite is the first animal to be found without a mitochondrial genome.
Researchers who study this organism don’t find the lack of mitochondrial DNA to be completely out of character for it. In fact, previous genetic studies showed that all sorts of genes found in its jellyfish cousins are missing from H. salminicola’s genome. Over time, it’s lost the ability to build everything from muscle to nerve cells. This genetic downsizing might be one of its evolutionary strengths — it allows it to stay small and to reproduce very quickly.
Researchers admit they have a long way to go before they can completely understand how H. salminicola’s anaerobic metabolism actually works. Some similar parasites produce proteins that allow them to siphon cellular energy directly from their hosts, and that could be how this parasite survives. More research needs to be done before we can fully understand this evolutionary oddity.
For the first time, researchers have found evidence that tweaking the brain’s immune system may help with memory and learning. And this discovery could lead to new ways to help people with neurodegenerative diseases.
We often use the terms “neurons” and “brain cells” interchangeably, at least on this podcast. But while neurons are what help you think, feel, and move, they’re not the only type of brain cell. They’re actually outnumbered by cells called glia [GLEE-uh]. In a recent study, researchers turned their attention to microglia — that’s a type of glial cell that shapes your brain as you develop, and deals with pathogens and injuries when your brain is in danger. In the study, researchers used genetically modified rats to explore the impact these cells had on memory. The results were, well, memorable.
They had two kinds of rats: some that had microglia and some that had been genetically modified not to have them. Then they put the rats in mazes to test their memory. At first, all of the rats did about the same. That wasn’t any surprise. After all, microglia fight infection and deal with damage — no one expected them to help with memory.
But then something weird happened. The researchers ran the same tests again after the mice without microglia regenerated the immune cells. The second time through, the normal rats did about the same, but the rats with the newly regrown microglia did an AMAZING job. All of a sudden, they were performing between 25 and 50 percent better than the normal rats. Imagine what it would be like for your memory to improve by 50 percent! That’s like remembering an entire Jonas Brother!
This is the first study to show this kind of effect, so there are still a lot of questions that researchers haven’t begun to explore — including why the rats’ memory improved so drastically. But they do have a theory. In ordinary brains, microglia change shape slightly when they’re dealing with an infection. It’s called an activated shape. When the researchers looked closely at the brains of the genetically engineered rats, they saw that the newly regenerated microglia didn’t look normal — they had the activated shape. They don’t know why.
The memory effect didn’t last. With time, the newly generated microglia lost their activated shape and started looking normal. As that happened, the genetically modified rats lost their supercharged memory.
Still, like I mentioned earlier this discovery might guide researchers in their search for new ways to help people with neurodegenerative diseases — like dementia, Alzheimer’s, and multiple sclerosis. But the next time you think about brain cells, spare a thought for your microglia. They do more than scientists ever believed they could.
ASHLEY: Today’s episode is sponsored by Purple Mattress. Here’s a question – how did you sleep last night?
CODY: The last thing anyone needs right now is to be stuck home alone AND unable to sleep. And if you’re struggling to get a good night’s sleep? Then you’ve gotta try a Purple Mattress.
ASHLEY: The Purple mattress will probably feel different than anything you’ve ever experienced because it uses this brand-new material that was developed by an actual rocket scientist. It is not like the memory foam you’re used to.
CODY: Yeah, the Purple material feels unique because it’s both firm and soft at the same time – so it keeps everything supported while still feeling really comfortable. Plus – it’s breathable so it sleeps cool! You’ll also get a 100 night risk-free trial – and if you’re not fully satisfied, you can return your mattress for a full refund! It’s also backed by a 10-year warranty, with free shipping and returns.
ASHLEY: You’re going to love Purple. And right now, our listeners will get a FREE Purple pillow with the purchase of a mattress! That’s in addition to the great free gifts they’re offering sitewide. Just text CURIOUS to 84-888. The ONLY way to get this free pillow, is to text CURIOUS to 84-888.
CODY: That’s C-U-R-I-O-U-S to 8-4-8-8-8. Message and data rates may apply.
Astronomers have detected the biggest explosion in the history of the universe. How’s that for a discovery?
If you ever feel like things just can’t get any worse here on Earth, then consider what happened to the Ophiuchus [oh-FYOO-kiss or OH-fee-YOU-kiss] galaxy cluster a few hundred million years ago. According to this new research, a supermassive black hole let off an outburst so big that it left behind a galactic crater you can hardly imagine — as in, it had a diameter the width of fifteen Milky Way galaxies. But this wasn’t a rough week: this was the biggest explosion humans have ever recorded, and it lasted about a hundred million years.
The Ophiuchus cluster is a huge collection of galaxies held together by their own gravity. It’s about 390 million light-years away, and it has the mass of trillions and trillions of suns. But most of that mass isn’t in stars, planets, or comets — it’s in the super-hot gas that fills space between the galaxies. As the gas cools, it’s pulled to the center of the galaxy cluster. And when that happens, things can get interesting.
Astronomers think the black hole in question is billions and billions of times as massive as the sun. As gas accumulates around a black hole, it swirls to form a disk. The pressure in all that swirling matter around a black hole can be incredibly high — so high that it can shoot powerful beams of high-energy particles out into space. It looks like that’s exactly what happened in the Ophiuchus cluster.
Based on data from four telescopes placed across Earth, astronomers think an unimaginably powerful wave of particles blasted out of the black hole, wiping out nearly everything in its path and ripping a gash in the galaxy cluster more than a million light-years wide. What’s left is practically a vacuum: empty space, except for a sparse fog of particles.
Astronomers noticed the huge hole in the galaxy cluster back in 2016. They toyed with the idea that the strange feature was the product of a black hole explosion, but they eventually dropped that interpretation because, well, it would have had to be the biggest explosion ever recorded. That seemed a little unrealistic. But as more data from other telescopes poured in, the researchers realized their original hypothesis was probably right. It really came from a black hole, and the explosion really was that big.
This is hardly the last word in explosive deep-space discoveries: the team’s equipment is about to get an upgrade that will make their observations ten times more sensitive. And while it’s possible for giant events like this to be the only ones out there, it’s more likely that in the future, we’ll find many more just like it.
ASHLEY: Let’s recap what we learned today to wrap up.
[ad lib optional]
CODY: Today’s stories were written by Cameron Duke and Grant Currin, and edited by Ashley Hamer, who’s the managing editor for Curiosity Daily.
ASHLEY: Today’s episode was produced and edited by Cody Gough.
CODY: Join us again tomorrow to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!