Today we explore how astronauts’ blood mutates when coming back from space, how our screens are aging us, and the potential extinction event of the snow crab.
Today we explore how astronauts’ blood mutates when coming back from space, how our screens are aging us, and the potential extinction event of the snow crab.
Astronaut Blood
Screen Wrinkles
Save the Snow Crab
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/astronaut-blood-screen-wrinkles-save-the-snow-crab
[SFX: INTRO MUSIC/WHOOSH]
NATE: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. Time flies when you’re learnin’ super cool stuff. I’m Nate.
CALLI: And I’m Calli. If you’re dropping in for the first time, welcome to Curiosity, where we aim to blow your mind by helping you to grow your mind. If you’re a loyal listener, welcome back!
NATE: Today you’ll learn about how astronaut blood is mutating, how our screens are aging us, and the potential extinction event of the snow crab.
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
NATE: Calli, astronauts are some of the healthiest people on and off the planet, but going to space might be messing with their blood.
CALLI: Whoa, what do you mean?
NATE: Well there are some concerns about the future of deep space travel and exploration, like the potential Artemis mission to Mars. According to new research, astronauts have genetic mutations in their blood from being in space, even those who went on short missions.
CALLI: It changed their blood?! And their genetics? I’ve always wanted to go to space, but that’s pretty concerning! It’s making me think twice about doing one of those commercial space flights the billionaires are promoting…
NATE: That's actually part of the reason they did the study! Commercial space flights are seeming a lot more possible. So, along with the Mars missions, it means a lot more people are going to be spending a lot more time in space. We should definitely know what that does to the human body.
CALLI: Alright so how did they pull off this study? Were astronauts mailing in their blood from the International Space Station?
NATE: The blood is actually from astronauts who were on space shuttle missions from 1998 to 2001. Scientists looked at blood samples that had been frozen for more than 20 years, from 14 astronauts, taken before their missions and after they returned.
CALLI: I know some of the ISS astronauts stay up there for like 6 months - how long were the Space Shuttle astronauts in space for?
NATE: On average, the astronauts, and their blood, were in space on missions that lasted 12 days. They were up there exposed to space radiation, as well as a bunch of other chemicals and systems from the shuttle needed to keep humans alive.
So all of the astronauts who they studied had these mutations in their blood called “somatic mutations.” The cells weren’t changing super dramatically but they were becoming EXACT CLONES of each other which is dangerous because it increases the risk of some cancers or heart disease.
CALLI: So were a lot of their blood cells identical?
NATE: In the grand scheme of things, no, but for the human body, yes. Under 2% of their blood cells were identical, which might not sound like a lot but it’s enough to be concerned about because at the time the astronauts gave their blood, they were all very healthy.
CALLI: Well what causes it?
NATE: These kinds of mutations happen when we are exposed to “environmental factors,” things you interact with that can be harmful, things like…radiation. Deep space is an extreme environment, meaning that the longer time you spend in space, the more likely you are to have these mutations.
We need to keep an eye on these astronauts who have been to space to make sure the situation doesn’t get worse. And now that we know this happens, we have to consider it as a potential risk for space tourism, and monitor these mutations on longer space missions.
CALLI: Being an explorer takes some risks, but I think for now, until we can completely stop these mutations, I might opt out of space tourism.
NATE: Me too, I will boldly stay where everyone else has stayed before: on earth.
[SFX: WHOOSH]
CALLI: Nate, do you know that feeling of staring at your phone for a while, only to realize hours have slipped by?
NATE: More than I care to admit to be honest.
CALLI: Well it might not just be your night slipping away, it could be your youth! Researchers have found that exposure to a ton of blue light, which comes from screens like phones, tablets, and TVs, could actually be accelerating our aging, and making our cells work less effectively.
NATE: You mean those reruns of Fresh Prince of Bel-Air are penetrating all the way to my…cellular level?
CALLI: I guess…that’s what I was saying? Researchers in the study took a group of fruit flies, and blasted them with blue light….
NATE: Wait, they did this with fruit flies?
CALLI: Ah, but humans use the same chemicals to communicate between cells as flies do!
NATE: Ok, I did not expect that. So they blasted fruit flies with blue light?
CALLI: Yes, they exposed one group of fruit flies to a ton of blue light, and took a second group of fruit flies and kept them in complete darkness. The fruit flies who lived in the dark actually lived longer than the blue light flies. When scientists looked at the flies who had been exposed to the light, they found a big difference in the level of “metabolites” in the cells. These are the substances cells use in their basic function. So if these levels are off, that’s a big deal.
They looked at the mitochondria, which is the powerhouse of the cell, and saw the metabolite levels were WAY up. That might sound good, but the levels of the metabolite that help cells communicate were WAY down. It's like your car has an overfilled tank of gas, but none of it is reaching the engine!
NATE: Oh how weird. You’d think more energy would be good, but if you can’t do anything with it…
CALLI: Well, the cells just don’t work as well. They kind of limp through their jobs and die early. And when you have cells that die early…that contributes to aging! Apparently the molecules that help communication between neurons also decreased, and that surely is not something you want.
NATE: I want my neurons firing at top speeds! So what do we do about this? I mean, I do need to use a screen for work, and sue me, I like to play video games on the weekend.
CALLI: And you don't have to stop! Researchers say it's more of a warning sign than a death sentence. The flies are going to be more sensitive to blue light than we are, and we likely will only have a big issue if we purposefully take in a TON of bluelight.
NATE: Oh that makes me feel better.
CALLI: But if you want to avoid aging, limiting your blue light seems like a pretty good strategy. Plus, it’s just good for you. Go outside.
[SFX: WHOOSH]
NATE: Let's talk about snow crabs. Back in 2018, there were around 8 billion snow crabs in the Bering Sea. As of 2021. There are somewhere between two and 7 million left. To put that into perspective, that's the equivalent to everybody on Earth dying except the population of Los Angeles County.
CALLI: Okay, I can’t even wrap my head around that number and that’s kind of terrifying. I feel terrible for the fact that I love eating snow crab now. What happened here? Where did they go?
NATE: Nobody knows for sure what has caused this. Now, we do know that snow crabs reside in colder waters in the north of the sea floor. When seawater cools, it becomes less salty and therefore less buoyant. And these crabs sink to the bottom of the sea. And there's no predators there which allow the crabs to grow in peace. At least that was the case until 2016, when the first of many heat waves stopped the water there from cooling and it allowed predators to prey on the baby crabs. So the most likely reason that this is happening is climate change.
CALLI: I feel like a lot of our stories these days are coming down to climate change.
NATE: Well, it’s a big, widespread global problem, so that makes sense. Now for this particular problem. The warmer waters also had the effect of speeding up adult crabs metabolisms, which created a mass starvation event. And as climate change progresses over the next few decades, these sorts of heat waves are going to become way more common.
CALLI: And this managed to wipe out almost an entire population in just three years.
NATE: Since the crabs were now floating in much more vulnerable waters, commercial fishermen also contributed to the snow crabs downfall. Many vessels that may have been looking for more conventional fish then discard the unwanted snow crabs. Fishermen who are looking for snow crabs may throw out crabs that are too small, too young, or that have discolored shells. And all of this is still bad for the snow crabs because over 30% of snow crabs who experience this shock of being dragged to the surface and thrown back will still die.
CALLI: Should we just stop catching them now? Like that seems like the fastest solution.
NATE: Even that isn't the perfect solution because crabbing is a big business in Alaska. It's a huge industry that pulled in $280 million in 2016. There are a lot of local fishers that depend on snow crabs for their livelihoods. Now these fishermen are aware of the problem and they're calling on the North Pacific Fishery Management Council to create better conservation measures and help rebuild a sustainable snow crab population. So this is a bad situation for the crabs and for the people. We would need to stop climate change and severely limit a booming industry.
CALLI: This is awful. Is there anything we can do about it?
NATE: As of right now? There's not much. But thankfully, the Alaska Department of Fish and Game did make the decision to cancel the 2022 snow crab harvesting season due to the potential extinction of the snow crab. For the time being, the remaining snow crabs are safe, but this might be a huge hit to the Alaskan economy.
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up. Astronauts who come back from space are different, at least their blood is! New research shows astronauts have a higher rate of mutations in their blood. While not a concern at the moment, tracking these mutations will be essential to ensure the health of past, and future, space travelers.
CALLI: That blue light from your phone might be tiring out more than your eyes. New research shows that excessive blue light can decrease your cellular function and speed aging!
NATE: In 2018, there were 8 billion snow crabs in the Bering Sea. Today? Less than 7 MILLION. Through a combination of climate change and over-fishing, the Bering Sea snow crab faces extinction at a nearly unfathomable rate. Thankfully, Alaska has paused snow crab hunting to reduce the risk of extinction, but unless a more sustainable system can be created, the halt may also ruin the Alaskan fishing economy.