Orcas and dolphins are now hunting together; Genetic root of psychiatric conditions; Black hole stars and cosmic ecology

0:28This episode is brought to you by Google Chrome. and eat each other and make festive. I don't want to go to your house for Christmas. To mark this festive period, we have the perfect story. Dolphins in the Pacific are cooperating with orca or killer whales to hunt and kill salmon. It's a heartwarming story of interspecies cooperation. That's us all over, isn't it? Yeah. Also on the show this week, we hear about a study suggesting that 14 different mental health conditions and psychiatric disorders in fact fall into just five groups when it comes to their underlying genetics. It's not that there's much wrong with people, it's more just how about redefining it.

1:05Also on the show, based on some new studies of supernovae, we're going to launch a new discipline called cosmic ecology. If supernova can influence planetary formation like that from further away, then that really kind of widens the net of how many Earth-like planets can be made. You heard it here first.

1:24welcome to the world the universe and us from new scientists i'm dr penny sarsha and i'm dr rowan hooper now orca or killer whales right they've been in the news a lot this year for attacking yachts um but here's something different in the pacific orca have been seen cooperating with dolphins to hunt and kill salmon alec loon is here to tell us the story alec the first thing that struck me about this was that can't the dolphins just catch salmon on their own? You'd think so, but we're talking about really big salmon. They're Chinook salmon, also known as king salmon, and they got that name for a reason.

1:59They can grow up to a meter long, up to 1.5 meters according to the U.S. government sites. So yeah, they get really, really big, and the researchers actually caught, they were using video tags that they attached to these orca whales, these killer whales, with an eight meter long pole. So imagine if that was your job to attach a tag to a whale with an eight meter long pole. But once these video tags were on the whales, and they could kind of see things from the whale's point of view. And one of the videos they got, actually, they saw a salmon, a dolphin bite a salmon, and the salmon escape from its mouth.

2:38So clearly, these salmon sometimes get too big for the dolphin to eat yeah wow they are big i've dived with a massive barracuda and they are scary enough but like a one and a half meter salmon that would be quite quite something it's basically me size so um what role then did the dolphins play in this cooperation if they can't actually be catching the salmon themselves sure so they the dolphins seem to get basically foraging. They get the leftovers because the whales are very, very messy eaters, as we were talking with the researchers. So basically, they'll dive down. They'll all dive down. They'll be using echolocation to find salmon on the dark, rocky seafloor.

3:20And then once the whales catch the salmon, they'll bring it to the surface. And then they'll use this grip and tear is the technique that as it's technically known. Yeah. Where they'll kind of whip the salmon around and tear them apart to eat them. And they'll also often share, you know, as we know, whales live in pods and have these family, these matrilineal families. And so they'll share with members of their family, often the fish. And so, you know, amid this whole process, there's all this kind of fish guts and scales and bits of fish being flung around. And the dolphins are able to swoop in and eat that and actually eat the fish rather than just bite at them as they escape.

4:03Yeah. You've got to imagine they'd be a bit wary, though, the dolphins, because, you know, orcas sometimes hunt dolphins, right? Absolutely. And so this is, you know, there are different types of, many different types of orca whales. The ones that were being studied here are northern residents. So they live in one place, and that's the north coast of Vancouver Island. Yeah. But there's also bigs killer whales, which are, I think of them, I guess, kind of as the angry teenagers of the whale world. They're roving the oceans after dark, getting into trouble everywhere. And those whales, they eat mammals, including dolphins.

4:41So if you're a dolphin, you want to stay well away from those killer whales, but you might be able to be much more safe around these fish-eating killer whales that are resident to Vancouver Island. And there's a lot of debate about what role these big killer whales are playing in this whole interaction, if anything. This is one of my favorite things about orca is you have these different cultures and the salmon eating ones tend to be more peaceful than the mammal eating ones. Those are the ones you're terrified of. And also orca are technically a type of dolphin too, right? They're all cetaceans.

5:15Yeah, they're all toothed whales, I guess is what they're all referred to as. So yeah, they're cetaceans, but some of them eat their own kind to a degree, I guess you could say. So, you know, orca are big. They're great at catching salmon. Why do they need to work with dolphins? So this is the big question here. These researchers are hypothesizing that the orcas use the dolphins to help them find the fish. We're talking about being at depths of 60 meters or more. It's very dark down there, very rocky, a lot of places for fish to hide. And so the idea is if you're just one whale using echolocation, that's like one spotlight.

5:53But if you have many, many dolphins out in front of you, And we're talking, you know, half a dozen, a dozen dolphins it can be. And they're all echolocating. That's many spotlights looking for the fish, right? So more of a chance that you will be successful and find fish. But it's also, you know, some people argue that there's nothing in it for the whales. I spoke to a researcher who was not involved but had done her own study earlier this year with drones. And she said that they found that these dolphin-whale interactions, there was nothing in it for the whales. and they thought that the dolphins were mainly just trying to shield themselves from the bigs killer whales, the mammal-eating killer whales, because those killer whales avoid the fish-eating killer whales, right?

6:38They don't come on their turf. So maybe the dolphins are kind of using the whales as human shields, or whale shields, I guess. Well, I mean, it makes sense, and they're going to be flexible with what they do and maybe opportunistic. And, yeah, so I guess there is something in it sometimes for them. and that's why they've observed it. But the observation thing is the key, isn't it? I mean, because I was trying to think of what other examples, and I can't think of any other interspecies examples of cooperation in marine mammals. And not even if you go onto land, there's not many, right? And marine mammals are, especially killer whales, are known for being fairly antagonistic usually when they interact with other species.

7:19I mean, there's a reason they're called killer whales. And there was a different study earlier this year where a group of these white-sided dolphins actually circled an emaciated whale and were swimming circles around him, possibly looking for when he died to be able to pick up some food or to make him vomit. Apparently, that is a thing, too. Apparently, they're into vomit. I don't know. But anyway, this emaciated whale ended up diving with members of his pod to kind of escape these dolphins and then didn't come back up. And so those researchers said that actually these dolphins probably exhausted this whale and contributed to his death.

7:54So we've got this huge kind of range of interpretations of dolphin whale behavior. And one of the researchers I talked to, also not involved in this research, he said, you know what, they're probably all right. Because these are smart creatures that have many different behaviors and are very adaptive, can quickly adapt to some local situation or local scenario that might be beneficial. And so he said, you know, we'll probably see all of the above. We'll see dolphins and whales helping each other, but we'll also see whales killing dolphins. And, you know, we shouldn't be surprised, he says, because, and again, we're happy to kind of anthropomorphize.

8:32This is interesting, I think, is that we're happy to anthropomorphize whales and say, oh, this whale is attacking my sailboat, clearly. You know, he's not just playing with the rudder. He's attacking me and kind of project that on the whale. but except in the one area where we probably should project and that's that this one species can have many different motivations and behaviors just like the human species can. So if this was a film, it would start off as a Disney film, like two friends, cross-species friendship, but then it would turn into a Tarantino film where the whale would kill the dolphin in a bloody battle of gore.

9:08And then suddenly it would jump back to the Disney film and everyone would be friends again. It's hard to patch it up. And for Christmas dinner, it'll be whale-fired. Thanks for that. So we talked a bit about are they just hiding the dolphins from these other nastier orca, or are they actually cooperating to hunt? And there aren't that many examples, are there, of interspecies cooperation that find food? I guess there are a few kind of well-known examples, one of which is octopus. So schools of fish can lead octopus to where crustaceans and mollusks are hidden on the sea bottom. That's been documented in the Red Sea.

9:48And actually in that case, the octopus kind of heard the fish a little bit and actually were seen to be punching the fish. If the fish weren't being productive and searching out food for them, the octopus would sometimes punch the fish out of the way. So again, interesting kind of, yeah, we can anthropomorphize the octopus in that situation to be punching. But then there's another really interesting one that involves our own species, which is honey guide birds in Africa have been known to lead humans to bee colonies in the trees. And interestingly enough, those honey guide birds will actually respond to certain human calls.

10:24So they appear to have learned a bit of our language to be able to do that. But there was that one with the dolphins as well, right, helping the fishermen in Peru. I think it was like the dolphins herding fish to be caught in nets and then they get some from the fishermen. I was trying to find more examples of animals working together specifically to hunt. And there really aren't that many. One I spotted that I hadn't seen before was coyotes and badgers sometimes work together to dig up ground squirrels. But most of them, when there are, you know, we love this kind of heartwarming idea of different species helping each other out.

11:02But usually it's for like protection or defense or kind of enjoying being in the shadow of another animal. Well, and also there's a very old one reported, ostriches and zebras often seen together. And the idea there is ostriches don't see very well, apparently, but do smell well. And it's the other way around for zebras. So if you band together, you both get a better sense of lions crawling after you and stuff. So that's been seen a lot to increase predator protection, like you say.

12:00high-tech living for researchers spending a week or more beneath the surface. It will allow marine scientists to live where they work, observing the ocean real-time over extended periods, testing new technologies and expanding our understanding of the oceans and how to live in an aquatic environment. Vanguard isn't just a habitat, it's the start of a new era of exploration where humans and the ocean coexist more closely than ever before. Find out more at newscientist.com slash deep. This week sees the publication of a big study suggesting that 14 different mental health conditions and psychiatric disorders, in fact, just fall into five groups when you look at the underlying genetics.

12:42Michael LePage has reported on this for us. Michael, what's the story? Yeah, this is an analysis of genetic variants in more than a million people. So that's by far the biggest analysis of its kind. As I said, the bottom line is these people had 14 different mental conditions. In terms of the genetics, they found that most of these gene variants fell into just five clusters, suggesting that there's fewer underlying causes than we think. This is really exciting, isn't it? Because we've known for a long time that mental health and psychiatric disorders, they sort of overlap and it's quite hard to work out where one starts and another ends.

13:18So this is kind of a step in the right direction. Yes. And I also I spoke to the lead author, Andrew Grotzinger, and he had a very positive take on this. that he was saying that it's actually, it's very common for people to be diagnosed with more than one sort of mental condition. In fact, he said the two thirds of people over the lifetimes, if they've had one condition diagnosed, two thirds would be diagnosed with more than one, which has surprised me, I didn't realise it's that big. But anyway, he's saying, you know, in that situation, people can think, oh, there's lots wrong with me. But what the study is showing, actually, there may only be sort of one in terms of the biology anyway, there's one underlying sort of condition and it's not that there's lots wrong with people it's more just how about we defining it not about the actual biology okay so you mentioned the biology there let's sort of zoom it straight in on that because we're talking about gene variants let's get clear about what they tell us because there are risk factors rather than it's not like you have the gene and you're going to develop this disorder right um it just increases your odds of developing something like Yeah, so this isn't like, it's not at all like classical diseases like cystic fibrosis, where there's a very simple, you have a mutation, you have this disease.

14:27What we're talking about here, people have done studies where they go, oh, people who have a certain, who've been diagnosed with a certain disorder, they're more likely to have a certain gene variant. But we're talking association. So we think if those gene variants are more common in people with a certain condition, then that's a risk factor, but we don't actually know that for sure. And in a lot of cases, we're talking a very sort of small number. So a specific variant might be a 1 % increase in risk, say. And there are hundreds of these different variants. And it's also clear that, you know, in different people, the same variants can act in different ways.

15:03So, you know, in one person, yes, a gene variant might be a risk factor. But another person, he might have a different, he might have different environmental lifestyle factors. Well, other genetic variants. Yeah, exactly. That would interact. Okay. All right. So just to get that clear. Now, tell us a bit more about what this study found then. Yeah, so just to go back a bit and put this into context. So when we first started looking for these genetic risk factors, the expectation was that for each of these sort of conditions that are recognised by psychiatrists, we're going to find specific sort of gene variants that predispose people to get in those conditions.

15:37But actually what has become clear over the past decade or so is that there's a lot of overlap. So suppose you've got bipolar. You might find that gene variants that predispose to bipolar are also predisposed to schizophrenia and so on. So there's this lot of overlap. And in fact, some people have even in recent years, there's even been the suggestion that there's like a single root cause of all mental disorders. Some people have called this P factor. Now, with this latest study, this is suggesting that the truth is somewhere in between. So they didn't find much support for a P factor. But instead, when they looked at these gene variants, as I said earlier, they all fell into these five groups.

16:15So we've got these sort of five different groups of disorders in terms of the underlying genetics. So we've mentioned schizophrenia, bipolar disorder. Tell us more about these sort of 14 conditions in the five groups. Yeah. So with schizophrenia and bipolar disorder, basically more than half of all the gene variants they found were common to both. So a large degree of overlap. The other really interesting thing is that they found that a lot of these gene variants, they were in genes that were active in excitatory neurons. So these are neurons that sort of turn on other neurons and make them more sensitive to stimuli.

16:49So that may be pointing us to some interesting biology. It's really like nuts and bolts about how your neurons work. And then the second group of disorders was major depression, PTSD and anxiety. And again, there was another interesting finding that they found a lot of these genes were active in what are called obligodendrocytes. Now, these are the cells that produce the myelin sheaths around nerve cells. This is what goes wrong with multiple sclerosis if you don't have those sheaths being produced. So this is another interesting bit of biology there. Yeah. And the third group was ADHD and autism.

17:25The fourth group was OCD, Tourette's, and anorexia. And the fifth group was very unsurprising. that was all the substance abuse disorders as they called so alcohol opioids cannabis and uh nicotine okay so to go back to the underlying biology the obligo dendrocytes that i had not heard of those ones before um and then excitatory neurons um what do these the findings about these these cells tell us about the biology well they sort of point in us perhaps in the direction or of something fundamental that's happening in the brains of people with these conditions. And so this is sort of a great avenue for further research.

18:07But just to be clear, so people don't get the hopes up, these are hints of what scientists need to look at. This is not like we're going to develop new treatments tomorrow. This is very much a long-term thing. It does feel like whole new avenues being hinted at, though. Absolutely, yeah. This is a new direction. And how could this change then how we view things? like so one of them was ADHD and autism we know that those are from co-occur or run in families now that we know that there's a kind of shared genetic basis too does that change how we start diagnosing or defining all of these different conditions?

18:41Yeah it's difficult so I think the analogy that Grotzinger used to me was that it's like if you get a cold and you've got a sort of you know you've got a runny nose and a sore throat and a cough you don't really want to be diagnosed with sore throat disorder and sort of runny nose disorder and cough disorder you want to be told I've got a cold so you want to find yeah you want to find that fundamental cause of of those symptoms yeah but this is at such early days still so this this is this is telling us something fundamental about these conditions but it's not quite at the point where it's going to be useful for someone going to see a psychiatrist and well I was going to ask about that because you You know, I don't know, is it every five years that the Diagnostic Statistical Manual of Mental Disorders comes out from the American Psychiatric Association?

19:32And, you know, there's always an update and like probably more. Some disorders get chucked out and some get put in. And there's a lot of sort of subjective debate and reshuffling. And I wonder how, if at all, this kind of new research into genetics might start to inform our diagnosis and this DSM manual. I think it does very much support the view that there are issues with these, which I think is not controversial at all. There are issues with these sort of criteria for making the diagnosis. Well, it's controversial if you're a psychiatrist because they will defend the DSM. but other scientists or scientists yeah well i mean grotzinger was yeah he was saying to me that you know the people well clinicians sort of often have this idea that there's a correct diagnosis based on a manual and it's very clear if you've got this degree of overlap between conditions and you know if you can't decide if someone has bipolar or schizophrenia that may be because they actually are somewhere in between rather than you know it's it's one or the other and And what he told me is he said, we're giving separate labels to things that biologically are not very separable.

20:48So there's that on the one hand. But then on the flip side, if we go back to that cold analogy, you know, sometimes when you've got a cold, you've got a sore throat, it's really hurting. You want to get a cold lozenge that's going to stop it hurting and you want to treat that symptom straight away. And so from a treatment point of view, sometimes even if these conditions are not separate in terms of the fundamental causes, you might want to be able to just treat that symptom and therefore it's useful to think of it separately. I feel like in recent decades with things like mental health conditions, there's been quite a transformation in terms of how most of us talk about them.

21:21Some of the taboos have been busted. Depression is no longer like a moral failing for most people. And maybe some of that is backsliding a bit at the moment. But this is kind of scientific vindication, isn't it? If your myelin sheath isn't the same as the average or if your neurons are more overexcitable than other people's, it shows that for many people with many of these conditions, there's a real biological basis to these kinds of things. Yes, absolutely. But we're very far from understanding that biological basis. But yes, and I think it also shows that there's a spectrum. We've probably, all of us in these rooms, I'm sure, we have some of these variants.

22:01It's a question of how many of the variants do we have and how do they interact with what happens to us in life. So it's a very complex picture, but, you know, there's definitely, you know, this study is showing there's definitely some interesting or some fundamental biology interplaying with various lifestyle and environmental factors. And, well, scientists have got a huge amount of work to do in future to try and unpick this and unpick this in useful ways in terms of, you know, treating people better and maybe hopefully even thinking of ways so we can identify people at risk and lower that risk in the future.

22:35Feels like a very exciting first step. Yes, yeah, it's definitely, I mean, this is by far the biggest study of this kind and it's revealing these new things that we haven't seen in the data before. Now we're going to turn to something a little more explosive, supernovae. That's when stars run out of fuel and explode. But they seem to be much more important for our existence than certainly I had any clue about. And I think this hints at a new discipline of cosmic ecology. Alex Wilkins is here to tell us about it. What's the story? So as Carl Sagan said, there's that famous quote, we're all made from star stuff.

23:12And that's the idea, basically, that all the heavy elements that we need for life, for Earth, the solar system, originated both in stars and when they exploded in these supernova, kind of spreading the elements across the universe and galaxy. but there's there's some quirks that which we don't actually know how those elements really get into the solar system and planetary systems it seems obvious but actually when you model this stuff you find that placing a supernova really close to a still forming star system can blow away all the matter and kind of upset that delicate balance and and just kind of it doesn't really work from modeling perspective then if you move it really far away you don't get the exact kind of ratio of elements that we see from our early early solar system right so this is a story about when these important elements are made in supernovae, how do they actually get into our solar system?

24:00And also, we don't have just any old elements in our solar system, do we? We have like a key makeup of certain ones and a kind of signature. Exactly. And we can look back to meteorite samples, which are these fossils from the really early solar system, and they preserve the exact kind of ratio of elements that we see. And these elements aren't just any random elements, they're very delicately balanced ratios of radioactive isotopes and elements and they provide a large amount of heat when the planets are still forming so you get these early what are called planetesimals which are these small rocks that later form the earth and these hot radioactive isotopes form supernova drive off a lot of the water without which we wouldn't have the right amount of water for life we would have way too much too much water for life i didn't realize that was even a problem Kevin Costner on Waterworld.

24:51OK, so this is what made me start thinking about a sort of galactic ecology or cosmic ecology, because, you know, you've got a distribution of the elements that we know are important for life, a non-random distribution. So it's like you could predict ecosystems just like we can predict what kinds of ecosystems you get on Earth, according to where physical conditions like heat and light that you have on Earth. but also you'll get that in galactic conditions if you're closer to your star or if you've got enough water and now if you've got these nutrient elements around. Yeah, yeah, exactly. But is there a chicken and egg thing?

25:30The signature that we think is essential for life is just what we've evolved for because that was here. No, that's a good point. Yeah, but that's all we can go on. So are we getting any closer, Alex, to working out this kind of distribution of where all of these different elements are in the galaxy? and beyond and how that might sort of predispose life in different places. Yeah, so there was this really interesting study that came out from research at the University of Tokyo. And they were basically modelling how you could get this balance of elements from supernovae. They found that if you didn't have it so close, you moved it a little bit further away, then there was this really interesting two-step process where some of the elements we made in the initial supernova explosion and then after that there would be followed these cosmic rays which would interact with the matter that was already in the solar system and produce the rest of them.

26:18And they found that this model really accurately predicted the kind of signatures we see from those early meteorite samples. Wow. And the fact that this works actually suggests something more interesting as well. It means that if supernova can influence planetary formation like that from further away, then that really kind of widens the net of how many Earth-like planets can be made because it means that you don't need to be so close to a supernova to have this kind of intended effect. When you're saying so close, is there a sweet spot? Obviously, you've already said you don't want to be too close because you'll get blown away by the supernova, but you don't want to be too far away because you won't get the good stuff.

26:56Yeah, it was about three light years or one parsec in the paper, so that's still a very, very long way away. I like to use the word parsec. You don't get to use it very much. About one parsec. Exactly, yeah. It makes me feel very professional. Well, you are. You're a doctor. yeah but not of cosmic biology not of cosmic stuff not yet cosmology not yet still time there was also this separate paper that was really interesting that was looking at a specific supernova explosion cassiopeia a which is one of the brightest in the sky that was thought to happen around the 17th century and there are debates about whether people could see it from earth at that time and it's been really extensively studied and they found when looking at this with a new telescope looking at the x-rays given off that there were some elements there that they just didn't expect from their models it was these elements with odd numbers of protons which in general are thought to be more unstable than elements with even numbers of protons really okay wow i didn't know that either amazing so you do get this cosmic ecology or eco ecology on on this grand scale yeah yeah absolutely so these odd numbered elements then um is that a good thing are they important for life absolutely so so these are things like potassium and chlorine that are things that we see everywhere in our oceans they're in our bodies exactly exactly so they're really important and and the fact that we saw them in cassia p a means that actually they might be more prevalent in other supernovae across galaxy and tell us uh where to look to to find these kind of planetary systems that have the same sort of elements that we know exist on earth so i think you might be onto something with the new field here this cosmic ecology brilliant well we'll accept applications now so does this mean that the galaxy is this patchwork of different levels of different elements it's not it doesn't just even out over time is it a kind of patchwork well yeah it suggests if you find areas where there are more supernovae than others and specific kinds of supernovae as well like cassipier a is a specific type of very luminous uh bright supernova um you would want to look for areas with those sorts of supernovae in them as well and ones that are close to other planetary systems that are still forming.