Today you’ll learn about how grapes have the potential to reduce the risk of skin cancer, how dogs’ behaviors are hardwired into their genes, and how underwater seaweed forests might be able to combat climate change.
Today you’ll learn about how grapes have the potential to reduce the risk of skin cancer, how dogs’ behaviors are hardwired into their genes, and how underwater seaweed forests might be able to combat climate change.
Cancer-Fighting Grapes
Dog Brain
Sea Forests
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/cancer-fighting-grapes-dog-brain-sea-forests
[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 grapes have the potential to reduce the risk of skin cancer, how dogs’ behaviors are hardwired into their genes, and how underwater seaweed forests might be able to combat climate change.
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
CALLI: Good news everyone! For people looking to eliminate some of the bad news in the world: it’s been discovered that the risk of skin cancer can be reduced drastically… with a daily glass of wine.
NATE: Okay, uh, topical? Or you drink it? How is this glass of wine preventing skin cancer?
CALLI: Well, I mean, I’m gonna go ahead and say that if you’re just rubbing wine on your skin it’s probably not for the best but I think they’re saying that imbibing is the way that this works, yes. So, this was the result of a recent study into how effective grape consumption can be on reducing UV-induced skin erythema, which is what happens when your skin becomes red and splotchy from too much exposure to the sun. It’s one of the key markers for skin cancer. As for why grapes, it’s because they contain hundreds of phytochemicals that have many health benefits.
NATE: Ah yes! Phytochemicals, they’re healthy and phyto-ey. Chemically?
CALLI: Okay, okay, I also didn’t know what phytochemicals were at first. They are compounds made by plants. Many of the compounds in grapes have positive effects on the central nervous system, gastrointestinal health, and vision, but one of the phytochemicals that inspired this study is called resveratrol. It’s a cancer chemopreventive agent. And if that term sounds familiar, that’s because it’s a natural substance that prevents cancer from forming.
NATE: Okay, I mean that sounds all pretty good. But what is it about skin cancer that these chemicals help with and not other types of cancer?
CALLI: It’s not really clear why grapes affect skin cancer primarily. But this wasn’t some random hypothesis: before this study, it was discovered that hairless mice who were overexposed to UV rays were given a spoonful of grape powder. Every case of erythema was reduced compared to mice treated in other ways. This led researchers to believe that grapes could specifically target erythema. So in the current study, thirty Caucasian humans were tested, split evenly along male and female lines. Each was given 28 packets of freeze-dried grape powder. They were told to mix them in water twice a day for two weeks. This is equal to three servings of fresh grapes every day.
NATE: Alright, I guess this is one of the less-invasive scientific studies I’ve heard of. Just drink this grape powder please. What did they find, drinking them grapes?
CALLI: Of the 30 candidates, only one participant didn’t see the study through to completion. But of the remaining candidates, nine of them developed a significantly greater resistance to UV irradiation. That number might seem low at first, until you consider that all nine of the participants had something called Fitzpatrick-One skin tone.
NATE: Oh yeah. Fitzpatrick-One skin tone. Fitzpatrick-One skin tone. Big fan over here. Long time fan. What is the Fitzpatrick-One skin tone?
CALLI: I don’t blame you. Didn’t know what it was either. Here’s something fun to know: The Fitzpatrick scale is how human skin color is classified. Type I always burns and never tans; they’re usually pale with freckles. I know. Type II USUALLY burns, and tans minimally. I think that’s where I land. The scale goes all the way to Type VI people, who never burn at all. The further down the scale you are, the less likely you are to suffer from erythema. The conclusion? If grape consumption reduced erythema in people who had Type I skin, it helped the people that are most vulnerable to UV-induced skin cancer!
NATE: Okay, that actually sounds like it’s doing some pretty cool stuff and any amount of reducing skin cancer sounds like a good amount to me. Getting back to the glass of wine idea, how many grapes really are there in a glass of wine?
CALLI: See, this is where it gets fun. Every bottle of wine takes about 300 or more grapes to make. If you fill a wine glass to the top, you’re filling it with roughly 75 grapes. So, the daily recommended amount of grapes is about 16 grapes. One NORMAL glass of wine every day is more than enough to test this for yourself at home.
NATE: That being said, you probably shouldn’t substitute your daily fruit intake for a glass of wine everyday.
CALLI: Speak for yourself.
NATE: This is something that can and should be emulated within the confines of a healthy diet
CALLI: I mean sure but where’s the fun in that? As they always say: a glass of wine a day may keep the erythema away!
NATE: I don’t think anyone says that before.
CALLI: I just did and I will tonight… with a glass of wine.
[SFX: WHOOSH]
NATE: If you have a dog, you might assume that the way dogs act is a product of how we train them, but it turns out - it’s just genetics!
CALLI: Okay, it can’t be JUST genetics because not training your dog is not something I want to start perpetuating. Just saying.
NATE: Plenty of training is good and necessary and does help form habits for your dog but there are a lot of things that are not trained in. For example, how bloodhounds are raised to sniff for certain scents or how many breeds of dogs are predisposed to attack when they feel provoked. There are a LOT of different behaviors to look into: did you know that there are over 350 different dog breeds?
CALLI: Wow, okay, I actually did not know that there were that many and I want you to name just, like, ten for me.
NATE: I mean I probably could come up with ten I definitely couldn’t come up with all 350. I’d be interested to look into that list and see which ones I’ve never heard of. But those 350 breeds were mostly created hundreds of years ago through selective breeding, when humans needed dogs for various purposes like herding and hunting - basically the cornerstone of how we survived was because of how specific dogs were bred. And all of those traits that dogs were bred for have been passed down for generations!
CALLI: So how would you even begin to track down that many genetic traits?
NATE: It wasn’t easy; to start, the researchers had to gather data from over 4,000 purebred, mixed-breed, semi-feral, and wild dogs. They used computational tools originally developed for studying single cells rather than whole organisms to identify 10 major genetic lineages among hundreds of dog breeds, solely through DNA data. What they found was that each lineage corresponded to a specific category normally used for tasks such as hunting by scent, or hunting by sight, or herding, and so on. Which meant that common sets of genes were responsible for most common dog behaviors, as long as the dogs were well suited for similar tasks.
CALLI: Okay, I think I’m following but just a little bit more of a breakdown. What does all of this mean for modern dogs?
NATE: At first, they didn’t know, so they turned to the real experts: the pet owners themselves. They used 46,000 behavioral assessment surveys they had sent to owners of purebred dogs to identify which sets of behavioral tendencies were unique among those dogs’ backgrounds. For instance, they found behaviors associated with “increased prey drive” were associated with terrier dogs, which it turns out contains breeds historically used for catching and killing prey.
CALLI: Huh, okay so I know that terriers are famous for killing things but we’re not talking about wolf-like instincts here, right?
NATE: No, terriers were bred for more like hunting rats and small things. They’re not taking down an elk anytime soon. After realizing that these traits were the same across dogs of a similar background, the researchers turned their sights onto livestock-herding dogs, because they display one of the most easily defined breed-typical behaviors: an instinctive herding drive, coupled with unique motor patterns that move herds in complex ways. And they got to work looking into how herd dogs’ brains were wired.
CALLI: Okay, we’re not gonna go into animal experimentation here, are we?
NATE: No, no, this is just - it’s nice don’t worry. They did do a simple brain wave reading of the dogs and found that variants found near genes were involved in something called axon guidance, which is a process that shapes brain circuitry. Additionally, those genes appeared stronger due to axon guidance process. It’s interesting since those genes are important for development in areas of the brain involved in social cognition and learned fear responses.
CALLI: Okay, does that mean that the herd dogs’ brains just rewire themselves to be more socially aware, but also more afraid?
NATE: Exactly. These genetic variants are found in areas of sheep dogs’ brains that are involved in brain development. You can actually see something like this happening in other species, including humans. For instance, the sheep dog has a gene called EPHA5 that has also been associated with human attention-deficit hyperactivity disorder, or ADHD.
CALLI: Okay wait, do sheep dogs have ADHD?
NATE: Is that really a surprise?
CALLI: No! It’s not, it’s very fitting!
NATE: They have like a sheep dog VERSION of ADHD. To simplify: what these researchers found in dogs can most closely be compared to how we measure human brain activity, and how it varies among different people. Which means that the same basic genetic toolkit can be found in use between humans and dogs alike!
[SFX: WHOOSH]
CALLI: Alright, it is time we start talking about seaweed… again.
NATE: Finally.
CALLI: And climate change… again.
NATE: Oh yeah, okay. Well, we’ve already kinda done a story recently about using seaweed for different products as a way to help curb pollution and climate change.
CALLI: Exactly! But we have some updates thanks to a recent study about the magnitude and distribution of the ocean’s forests.
NATE: Okay, tell me more.
CALLI: So, to back up a bit, seaweed is a natural absorbent of carbon dioxide, from both seawater AND the atmosphere. Some seaweed forests have as much carbon as the entire Amazon rainforest! Unfortunately, there’s been a lack of understanding of how long-term seaweed could be seen as a solution because it doesn’t have a root system like other sea plants like mangroves or seagrass. Those root systems trap the captured carbon dioxide underground, so when forests like these don’t have them, we’re not sure what happens to the carbon dioxide they absorb. Which is what makes the recent discovery of how many seaweed forests there are on Earth such a groundbreaking find.
NATE: How many seaweed forests are there? I mean I know the ocean’s a big place, it’s got a lot of space for seaweed forests but… what have we found?
CALLI: It’s big! Combined, seaweed forests cover around two and a half MILLION square miles underwater. That’s about twice the size of India - and knowing there’s this much seaweed out there, AND where it grows, means that scientists can now finally begin to understand seaweed’s role in cutting back on climate change.
NATE: Wow! How did they even discover this?
CALLI: An international group of scientists from eight countries were led by Dr Albert Pessarronda from the University of Western Australia. These researchers manually went through hundreds of studies – including local plant data records, online repositories and citizen science initiatives – to figure all of this out. Unfortunately, they also discovered that the forests are in danger.
NATE: Of course. Set me up just to knock me down. What’s wrong with the forests?
CALLI: So, rising sea temperatures, pollution and invasive species. Along the northern California coast, kelp, which is a species of seaweed, has declined by more than 95% over the past several years because of sea urchins.
NATE: Stupid spiky little sea bugs.
CALLI: They’re delicious. It’s kind of a disaster and kelp forests have been overlooked and less studied compared to coral reefs, which makes it difficult to understand how they are changing. Even though we know how many seaweed forests there are now, we don’t have them mapped or even monitored. In fact, kelp grows in cold waters in some of the choppiest, roughest coasts in the world.
NATE: Ah, so it’s definitely hard to look at, gotta send divers down and stuff, alright. So what is it about kelp in particular that we should care about as opposed to say, normal seaweed?
CALLI: Well it’s still normal! Kelp is the largest seaweed species, and is able to grow up to 175 feet tall, providing an abundance of food and shelter for fish, other marine animals, birds, and - yes - humans. Plus, Kelp forests along North America’s Pacific coast provide habitats for southern sea otters, and gray whales use kelp forests as a haven from predatory killer whales. If kelp forests aren’t preserved - it’s more than humans at risk.
NATE: Alright, that makes sense. So what’s been done to help fight this?
CALLI: For now, scientists are diving into kelp forests all over the world to monitor progress and figure out ways to stop the death of these forests. That said, as science continues to develop smarter technologies to track kelp, like drones, satellites and AI, scientists hope that research can shed light on the role of kelp in fighting climate breakdown. Like for instance, how underwater forests can go a long way toward helping with other global crises - such as the world’s food security crisis.
NATE: Howso?
CALLI: By examining hundreds of studies of seaweed growth across the world, it was found that ocean forests are more productive in growth than intensely farmed crops such as wheat, rice, or corn. Seaweed has been mass-consumed in Asia for centuries, but it hasn’t caught on in quite the same way in the western world. That being said, as food security becomes a bigger and bigger issue, the western world might want to consider adapting - especially since more of a spotlight on preserving seaweed could help fight climate change!
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up.
CALLI: Grapes are filled with countless nutrients and phytochemicals that can lead to a longer, healthier life, but did you know they also contain powerful chemopreventive agents? This means that a daily serving of grapes can actively reduce UV-induced skin eritheema, as well as skin cancer. So the next time someone tells you to put down the wine bottle, tell them you’re drinking it for your health!
NATE: Have you ever wondered why dogs of certain breeds all seem to act and react in similar ways? Turns out it’s because of genetics. Through years of breeding and crossbreeding, dogs have developed highly specific behaviors inherited from generations of living dating back centuries. And new research suggests that some dogs may even develop versions of ADHD - meaning humans and dogs are a lot more alike than previously thought!
CALLI: Seaweed: the potential savior of mankind? A recent analysis of underwater forests has discovered that seaweed forests take up a portion of land that’s double the size of India. By locating these forests and making sure they stay preserved, we could potentially combat climate change, and even global hunger, due to the many restorative aspects of seaweed!