 starting the sixth mass extinction. That's a question that we really have to discuss. And for that discussion, we here at Zanktec, I'm Jay Fiedel, and our discussion today is on community matters. We're going to discuss that with Dr. Robert Cowey of the Pacific Biosciences Research Center at UH Manoa. Welcome to the show, Robert. Nice to be here. So you were in the paper not too long ago about the sixth mass extinction. And that's enough to make you, you know, turn your head a little, what, what, what, what, what's going on here. But it's not happening right now. I guess the issue is, is it happening soon? Can you give us a, a pre-see on what it is this mass extinction we should expect? So there have been five mass extinctions prior to what this one might become. And the rule of thumb is that that means that 75% of all species on Earth vanish. That's the sort of rule of thumb definition of a mass extinction. This one is different from the previous ones, because this one is entirely caused by humans, human activities. And at this point, we can't say that the sixth mass extinction has happened, or even perhaps that it is happening, because you can't say that it's, that we've reached 75% of species going extinct until it's actually happened, right? And so what we said in the, in the paper that was recently published that attracted a lot of media attention was that, well, at the rate we're going right now, and we estimated that rate of extinction, at the rate we're going right now, then at some point in the perhaps not too distant future, particularly as the rate increases, we will probably come to a mass extinction. At this point, we would say that we're probably at the start of it. So what, so if 75% is sort of a benchmark, where are we now? Are we at 1%, 2%, 5%, where are we? We're at maybe 10%. Yes. And the numbers that we extrapolated based on some research of our own that we did a few years ago, suggested that between 150,000 and 260,000, so give or take 200,000 species with a bit of sloppy the way, have gone extinct already since the year 1500. And I can explain why the year 1500, if you're interested in it at the moment. Yes, please. All right, well, let me come back to that because the point of that roughly 200,000 species going extinct since 1500, is that that has a proportion of the known species that exist on earth, those that we found and described and given scientific names to, there are about 200,000, there are about 2 million of those out of maybe 10 million total species, the rest that we don't exist yet, we're just estimating that. But of those 2 million species, we estimate that around 200,000 have already gone extinct. So that's around 10%. That's a striking number. And a lot of those species are not the elephants and the tigers and so on that everyone hears about being really critically endangered. But it's all the things that we don't know so much about, the little creepy crawlies and so on, but there are myriads of them in the Amazon jungle that's not being explored and is being destroyed as we speak. So it's a number. So I'm thinking of a British scientist who was in the media a lot. He's made some movies, David, I want to say David Attenborough's. Yeah, I met him at the Bisham Museum 20 odd years ago when he was filming the land snails, the Hawaiian land snails, free snails that he was making a little tiny section of one of his life on a movie tour, not one of that. Well, one thing that he always says and repeats and repeats is that it's all interdependent. And if you lose a species or a group of species, that's going to have an effect on other species. And it's not in a silo. It's all connected in many, many ways. I guess that's the general knowledge, that's the general point. And so if we have lost 200,000 species in the world today, how would you say, looking back, looking back to 1500, how has that affected us? Well, that's a really difficult question because no one's really, I think, tried to answer that. We can speculate, you know, a lot of those 200,000 species are going to be, like I mentioned, the little creepy crawlies in the jungle somewhere. And the issue there is you've undoubtedly heard the analogy of a plane losing a rivet here and there, still carrying on flying. So it still functions as a flying plane, even though it's lost a couple of rivets here and there. Now it will lose a couple more, now it will lose a couple more, but eventually it'll come to a point where it falls out of the sky, right? And so I think that there's probably a lot of redundancy among species out there in terms of what their functions are, but their functions ultimately are including the functions of these little creepy crawly slugs and snails, which is what I work on, and insects, myriads of insects and spiders and beetles and etc., etc. So as swaths of them disappear, then ecosystem function is ultimately damaged. And I had a graduate student some years ago, Marty Meyer, and he published a couple of papers in which he described some experiments that he'd done in what we called mesocosms. They're like cages that he set out in the rainforest on the Big Island. And what he showed was that the snails, in particular, the snails were responsible for, I think it was something like 30% of the turnover of nutrients in the system. And I mean, he was, unfortunately, having to work with non-native snails because those were what were abundant in the rainforest and the native ones disappeared. Perhaps those non-native ones were fulfilling the roles that some of the native ones previously did, but since we don't know what the roles of the previous ones were, we now know what the roles of the invasive ones that he worked on are. We can't really say whether they have fulfilled those roles or not. And so it's very, that comes back to what I started off by saying, it's very, very difficult to say what's changed. Since we don't really know in sufficient detail, yeah, we know that there were snails there, but we don't know what they did exactly. Because snails don't all do the same eight different things. Same with insects and so on. And so, yeah, you can probably say that if some top predator goes extinct, then some of the big ecosystem impacts. So, for instance, when wolves are extirpated, okay, gray wolves are not extinct yet, but they're considered endangered, even though the fish and wildlife service doesn't acknowledge that anymore. When wolves are extirpated from a particular area, then the deer increase in numbers and they eat more of the vegetation that believes on the trees and the flora, the tree flora changes dramatically. And that's because the wolves have disappeared. So if wolves go extinct across the whole swath of Northern North America, then maybe there's going to be some regional change in flora. So things like that can occur, I think. But like I say, it's very, very difficult to say how things have changed since 1500. We can look at how environments have changed, how humans have impacted environments, but is the change specifically related to the loss of particular species or group of species? That's very, very difficult to say. Well, that's so interesting. And it begs to say this is very, very complex. And the more you find, the more you need to find, the more you know, the more you need to know. It's our whole world. It is our whole world. But you know, it reminds me when you talk about snails on the big island, I think of rat lungworm. And I know you were on our shows a few years ago to discuss that. So I say to myself, well, rat lungworm could be eradicated if you just eradicated the snails. Maybe I'm wrong, but that's part of the life cycle of the worm. On the other hand, if you eradicated the snails, you'd have other implications. You'd have other subtle effects, maybe not so subtle effects on the flora and the flora. The same thing with other organisms that carry pathogens or that are pathogenic. I mean, we are always tempted to eradicate them to avoid the pathogen, like mosquitoes carrying any number of mosquito diseases. But if we do that, if we knock out a particular species or group of species of mosquitoes, we'll pay a price in some other way. And that all begs for further research, doesn't it? Well, that's absolutely right. I think specifically with the mosquito issue, there's actually a group of people heavily engaged right now here at UH in developing potential control measures or very sophisticated genetic approaches for the control of mosquitoes here in Hawaii. Because for the exact reasons that you mentioned, the difference here is that those mosquitoes were not native. And they come here, they're a menace to us. We don't like getting bitten by mosquitoes when they carry disease. But they also have caused the extinction of a number of native Hawaiian bird species, of course. And so there are multiple ramifications of having mosquitoes here in Hawaii. But you could argue that getting rid of them is reverting the environment back to where it should be, perhaps, or where it was at some point in history, prior to the introduction of Los Pitos, which are not native here. So, you know, it's complex. It's complex socially as well. Yeah, and that's sure. And I want to hear about the social part, but it just strikes me that biology, which is your field of study, is not static. That you have to, it's beyond looking at the ecosystem now, today, and all those millions of connections and effects of, you know, those domino effects of, you know, acting on one thing in the environment, having all this secondary effect. It's more than that. It's you got to look back historically by taking a slice off a tree to see what it was like in 1500 and 1600 and so forth. And then also you have to look forward. You have to look forward to that 75% of the mass extinction, which I want to ask you about. But you said social implications. Tell us about the social implications. It's kind of related to the social implications, but there are people here and we discussed this in the paper, who not just here in Hawaii in the world, who think that, well, let me back up. I think that this crisis is horrendous. And I think that we should be doing something dramatic to try to stave it off. I mean, I'm very pessimistic about that. I don't think there's social aspects of it. I don't think there's the political, economic, societal will to actually do that. They would require huge changes. I don't even know if I'm prepared to suffer the hardships, if you will, to exaggerate perhaps, but it would be required to reduce my carbon footprint, for instance. There are people better than me who are able to do that. But anyway, that's one thing. There are people who, unlike me, don't actually care. There are people who think, well, humans are just animals. We evolved from some other humanoid animal, ultimately. And of course, some people don't believe that, but that's a whole other story. So we did evolve, and they say, well, we're continuing to evolve. We're just another animal doing its thing in the great sort of evolutionary maelstrom. Evolving into extinction. But quite possibly. But the thing is, they think it's okay because they think that they don't think that humans are going to go extinct. They think that we're just doing our own thing, and that's evolution. And if human evolution means that 75% of biodiversity on Earth disappears, then so be it. That's just the way nature works in the greatest scheme of things. There are other people who go so far as to not only say, that's a sort of laissez-faire attitude. There are other people who take an active attitude in which they think that, sure, there's a biodiversity crisis. Great, let's manipulate it for our own benefit. And who's going to define that benefit? That's a big question for me. And actually, the answer is probably fairly straightforward. It's going to be politicians and economists, business people, not people like me who don't have any kind of or very little influence over those aspects. Well, that sounds like exploitation, isn't it? Yeah, sure. But they're fine with that, because their focus is the benefit of humanity, whatever that means. And there are some benefits that I talked about, like developing countries, increasing their GDP or whatever the economic things are that allow those people to have the kind of lives that we have. And maybe that's a good thing. But isn't this run a parallel to the dichotomy of social thought over climate change in general? There's a lot of people that either deny it or say, well, that's the way it goes. Maybe it'll return in another million years to the way it was. We can't do anything about it, so we won't worry about it. Or if it gets worse, it won't affect us. It'll affect our children. Same thing with mass extension. If it gets worse, it won't affect us. It'll affect our children. And they will have better science then to deal with it, which it may or may not be true. But can you talk about that, the comparison of the social response to this notion of extinction and the social response to the notion of climate change? Like you've implied, it's very similar. It's all ultimately about this whole science denial thing. They're denying that there's climate change. Or they're saying, like you said, it'll go away. It's just the natural cycle of the climate, the climate. Just like I just described about, well, it's just humans evolving. And this is what humans do when they evolve. I think that the whole science denial thing is very scary. And it's not just climate change and biodiversity extinction. It's COVID, vaccination. That's everything that we talk about in the news right now. I'll tell you a funny story. When this paper first came out and we released the new age release press release, one of the first people to tweet was, and this was in response to a tweet actually about our paper, was Elon Musk. And he tweeted basically, and I'm paraphrasing here, he tweeted saying, yeah, everything is going to go extinct. You've actually, when the sun expands and eats up the earth, including humans. So we need to become interplanetary. This is just piggybacking on our paper to self-serve and get people to support his space exploration. Because you know when the sun is going to engulf the earth, five billion years from now. Yeah, well, it's all out of science fiction, but it may or may not be true. Science fiction changes. So a couple of things that you mentioned I'd like to inquire about. Number one is, this may be a hard question, I'm not sure. But we have a continuum here at say 10% extinction now, and say 75% where it really is destructive. What is it like if I wake up one morning at 75% extinction? What kind of a world do we have with 75% extinction? What we'll have and sure it's speculation, but we're on the road to this already. We know that. And Hawaii is a microcosm of this. If you think about it, before any people arrived here in Hawaii, there were all those birds that have now gone extinct. There were all those plants that have now gone extinct. There were all the snails that have gone extinct. And most obviously the original Polytheon people who arrived here caused some of that because of course they had to make way for their agriculture, for their habitation, and so on. But it ramped up once Europeans, wetlands, Europeans, Americans, what have you got here? And it continued to ramp up. And we published a paper back in 2015 about the group of snails, a family of snails, native Hawaiian snails that are only found here in Hawaii. In this group, which is called a family, there were 325 species. And we now think that of those 325, only maybe about 20 are left alive. So there you've got more than 75%. But that's just within that one group. And it's not to talk clear what that group did or didn't do that is different now because the habitats all changed anyway. So what's happened here is first of all we've got all that extinction. But then we've got a lot of invasive species here. You've heard the expression, endangered species, capital of the world. Also the invasive species, capital of the world. And so everything's changed here. The fauna, the flora of the islands, what's left of the original ecosystems and plants and animals are mostly confined to the high, not entirely, but mostly confined to higher elevation, mountain tops and so on. What's down below, I mean, we never see a native bird in our yard. We never see a native snail in our yard. We've just got bull bulls and miners and slugs. And so we're already seeing what it's like to have some loss of native biodiversity and its replacement by other plants and animals. Most of those animals, which is what I know more about, but plants too, are species that are not, obviously they're not just nature to Hawaii and nowhere else because they come from somewhere else. But these are species like the giant African snail, which everybody knows, that are now pretty much all over the tropics. And so what you're having is a homogenization of faunas and florets. So replacements of the Pacific Island is a classic, the classic example of this, not just Hawaii, but all the islands of the Pacific, where you had the snails, for instance, you had maybe 5,000 different species of snails, each living on a single island or a small archipelago. Those are disappearing and those are being replaced by half a dozen or 10 or 15 non-native snails introduced by people that have now spread all over the Pacific. So the fauna has become significantly homogenous across the islands of the Pacific, whereas before it was very diverse with local endemic so-called species. What's wrong with homogeneity? I mean, certainly people are, I don't know if nostalgic is the right word, but they harken back to a day when Hawaii was more isolated and had its own ecology and it was different than anywhere in the world. And now we're becoming homogenous. And so what's bad about that? What have we lost and what has replaced it in terms of the benefit to humanity? Okay, I think that an issue that we haven't touched on is benefit to humanity simply in terms of the joy and the pleasure we get from not just seeing nature, but knowing that diverse nature exists out there. I mean, to exaggerate a bit, how would you like your grandchildren not to be able to see a live tiger, even a tiger in a zoo, because tigers have disappeared. And we feel the same about these little things. The snails that we work on, this group that I call the paper work, these snails are going extinct at a rate of knots, and particularly across the islands of the Pacific. And so what we at the end of the paper exhorted scientists like me, I'm too old, I can't hike anymore, but other younger people who can do heavy duty field work could get out there and collect representative examples of every single species that they can find, particularly the ones that have never been described before. And there's a truckload of those out there that are already going extinct, we're finding them already extinct, we're finding the shells. And so collect them, put them in museum collections. It may take 300 years to actually describe and name them all, but at least they'll be there so that ultimately 200 years, 300 years, 500 years from now, those, our descendants would be able to see all those snails, and it could be, it could be lions, it could be elephants, it could be rhinoceros, it could be birds or crocodiles, whatever. And know that once upon a time, there was this spectacular diversity living on earth that we've unfortunately lost. And I think that maybe that's an emotional response, but I don't think there's anything wrong with that. There's a tropical garden, tropical preserve in Manoa, up the back of the valley there, I forget the exact scientific term of it. And they save things, they save plants that no longer have an environment in which they can survive with the notion that one day- Part of New Lakes, Delay and Alboree from Hawaii. That's it. We had a show there once a few years ago. And what I remember was a very interesting notion that one day we would take all these plants that we were saving, carefully, carefully saving in the arboretum, and return them to the environment that would be nutritious for them if it ever came back. But it wasn't clear that that environment would ever be available again. What are your thoughts about that? Is that a worthy effort? I think I do think it's a worthy effort. And we're doing the same with the snails. The DLNR and the Bishop Museum both have big captive rearing, captive breeding populations of native Hawaiian snails. And the goal is to get them back out in the field eventually. And the DLNR, along with the arming people who own a lot of the land in Oahu, are actually doing that in a limited way by putting them out in predator-free eggs closures. So these are fences around an area of habitat that's suitable for the snails. And it keeps out the various predators that are one of the major causes of the extinction of these things. So it seems like pie in the sky to hope that things will go back to normal. Not normal, but what's normal. But back to sort of more native habitats. But it's not inconceivable, if there were a will, at least in small areas to do that. I mean, I think that New Zealand does a great job in some of these regards. I went to the Nature Reserve Bay, right in the centre of Wellington almost. But it's been completely fenced off. You have to go through double doors to get to it, like a fair thing. You know, like a tropical disease laboratory. Yeah. And, you know, they had all these native plants and native animals, things that had been excavated from everywhere else in that area. And so I think it's not entirely pie in the sky, but there has to be a will. And that's what is the problem. That takes us to the study of biology in general. I mean, we talk about this very complex global ecosystem, which is being homogenised as we speak. And we're losing, you know, various elements of it. We don't know what the cost is to lose those elements. And then we have biologists like you who see this happening. And you're not the man on the street, you're a scientist. The man on the street doesn't know about this. And then ultimately, maybe biology will get to be a science that will be able to preserve these species, be able to understand more completely how each one affects the other, and thus to save the planet, save the biodiversity from extinction. I mean, do you see biology and what you do in biosciences as a science that can actually affect scientifically this mass diversity extinction? I can, but I don't think I can see it. I can see the way to do that. I mean, like, even if it's just by collecting a whole lot of stuff that will ultimately go extinct, so at least we know what was here once. There's lots of other good projects, conservation projects out there, like the Bishop Museum efforts and the DLNRM efforts. And globally, you know, people are trying to save rhinostasis and digas and whales and what have you. And those are all laudable efforts, and we need to do that, because some of those will be successful, at least over the short term, and maybe things will change a little bit as time goes by. But the reason I think that we should collect stuff and put them in museums is because I'm ultimately pessimistic that there are biologists who want to do this and there are biologists who probably could do this. There's not enough of them, of course. But is there a societal will to do it? That's the $64,000 question, because without that societal will, which means the money, it'll follow the money. It needs money, and it's not effective. I mean, if you make a comparison to climate change, we seem to have a problem in finding, you know, the collective will to address the phenomenon. And so that brings me to one more question I would like to discuss with you. That is, when you say that at 75%, we, that is, I guess, the human species, is extinct, that's pretty serious. No, I didn't say that. Okay, wait, sorry. Are we at risk of becoming extinct? And how does that work? I think we are at risk, ultimately, because depending on when that 75% mark is reached. I'm not a silly arbitrary number, but whenever that's reached, probably ecosystems are going to be changed dramatically. And we're not just talking animals with plants in terms of what goes extinct. Certain species of plants go extinct, you know, water sheds get damaged. We've still got an expanding global human population that's craving water, and the water's disappearing for not only these kinds of reasons, but because of climate change reasons and so on and so forth. So, like you say, it's all interconnected. And ultimately, you know, it could come crashing down. I think that it is terribly pessimistic to say, but it seems to me that the way that we're going to go extinct is because we're all going to fight each other and kill each other. That could happen a lot sooner. But I think that that's ultimately how we'll go extinct, because, and I don't think technology is going to solve these problems. I think technology is, if people think that that's going to happen, then I think they're in a dream world. So one more thing related to that, you know, the sixth mass extinction you mentioned early, and I saw in the summary of your paper, is different than the previous five. How far did the previous five get before they somehow stopped? And what was the effect on the global environment of each? Have we been sort of stepping down into a lesser environment with each one of these five? What happens is that some cataclysmic change in climate, for instance, or there's a sudden huge volcanic eruption on a grand scale. One of these was, way back in, one of these extinctions was caused by volcanic activity in India. And of course, the fifth extinction, which is when the dinosaurs went extinct, was caused by an asteroid landing in the Yucatan Peninsula of Mexico. That's the generally accepted theory. And that was like 100 nuclear bombs going off and causing huge, huge change in climate as a result of the whole place being clouded over and so on. And that's the basic thinking on that. Other than that one, the previous four mass extinctions were largely constrained to marine environments, at least that defined by the marine environment. So a lot of marine invertebrates going extinct is what defined the previous four mass extinctions. It's thought that those were probably caused by things like volcanism, changing the atmosphere, carbon dioxide levels increasing, acidity in the oceans increasing, but those kinds of earth chemistry changes happening. I'm not an expert in those areas. That's the geologist's domain. But what I know is that actually that's how it will change. I mean, these things resulted in climatic changes, raised temperatures or lower temperatures, and those caused those extinctions. Is it fair to say that the human species is actually a result of these previous extinction stages? Well, of course, because when the dinosaurs went extinct, that made way for abolition of life diversity of larger mammals, of which we're the product. And is it fair to say that the species will survive the sixth extinction or is that so different? I mean, aside from the possibility of war and self-destruction, is that so different? Right, exactly. Is it so profound, the sixth one that we're talking about, you wrote the article about, the sixth one will do us in or ultimately will create an environment in which we cannot survive as the human species? I don't feel qualified to give you a straight answer on that. I don't think anyone knows how it's going to pan out in sufficient detail in terms of what goes extinct, what doesn't go extinct, what environmental changes take place as a result of those extinctions. Interacting, of course, with climate change, that to be able to say, yes, we'll go extinct or we'll decline and we'll go back to living in mud huts or what have you, or caves or whatever. Or whether we find the technology, and I don't think that's going to happen, to fix ourselves somehow, to fix the environment, to make it habitable in a good way for humans. So I don't think it's possible to say how it's going to pan out. It won't be for a while though. We're not going to be here anymore. Okay, I told you before we started that I loved biology in high school and all my friends did too. My last question to you, Robert, is it more appealing now than it was? Is biology something that any viewer of this program should consider studying? Sure. There's all sorts of fascinating stuff in biology. For example, you've heard of the microbiome. We've probably had microbiome people on your show before. That's the new frontier in biology, one can argue. We don't understand the vast majority of what the importance of the microbiome is in not only testing our own bodies, but in other animals, in ecosystems, in the ocean. I think there's wide open frontiers in biology. That can be exciting. I've spent nearly 50 years as a professional biologist. But getting on full. To be honest, I've enjoyed every minute of it. And I still enjoy it. I still am fascinated, ultimately, I'm fascinated by animals. That's what it looks like. That's been the driving force of my career. I'm fascinated by animals. It reminds me of the French headline after 9-11. I can't do exactly the right pronunciation. It was something like Newsom's Two Zemelegan. We are all American. The reason it reminds me of that is, I think to some extent, all of us, whether we studied biology in high school, college, or graduate school, we are all biologists. We live in a world of biology and we really have to see it that way. But you can't avoid it. We eat it. We get to do this problem. Thank you, Robert. Robert Cowey, UH Piosciences Research Center. Really appreciate you coming on the show. Thank you. That's been fun. Thank you. Aloha.