Conservation genetics: how to use molecular tools in management

[BELL RINGING] Welcome back to the Bio-Audio Podcast. Today, we're going to talk about conservation genetics with an old friend. Would you like to introduce yourself? I'm Dr. Christina Davie. I'm an assistant professor at Carlton University in Ottawa. OK, so could you describe what do you mean by conservation genetics or conservation genomics? I think the term gets used in two different ways. I think it is often used to describe the application of genetics to assist in conservation efforts, which to me is the goal of conservation genetics. But I think there are many cases where the term gets applied to genetics studies on species that happen to also be at risk, where the application to recovery of those species is less clear. And that's a use of that term that I'm less fond of. OK, so why is using genetic tools an important concept in conservation? Why don't we just use observational skills or other tools we have? What more do you learn from a genetic tool? If we could see everything that all the different wildlife species are doing, maybe we wouldn't need the genetic tools as much as we do. But the fact is that wildlife are really difficult to observe at a scale that will let you understand what's affecting populations and what's affecting a population's risk of extinction. So in conservation science, we're usually concerned with populations that are at risk of extinction. And that typically means either a population that's declining very quickly, even if it's still large, or a population that's become very, very small. And using genetic tools can help us understand how far individuals are moving, which, if you have a very small species that you can't track easily, is important. It can tell us who's mating with who. And it can tell us how high the genetic diversity in the population is. And the reason that that matters is that populations with high genetic diversity are more likely to contain the genetic variance that will let them deal with the next big environmental change, whereas when a population gets very small and maybe comes inbred, they lose a lot of genetic diversity. And the chances that they have that genetic variant that will let them get past the next new disease or the next new crisis is much lower. If I was to look at two populations, let's say they're the same size, is it reasonable to assume they have similar levels of genetic diversity or is that a bad assumption? So if those two populations belong to the same species, so we assume that they have the same life history traits, you could still have different genetic diversity in the two populations, even if they're the same size. For example, if one of those populations had gotten really large again after a dramatic crash in population size, they would have lost a lot of genetic diversity during that crash. And even though the number of individuals has recovered, you might still see that low genetic diversity because a small number of individuals made it through that crash, whereas a population that has an experience to recent crashes like they have much higher genetic diversity. So understanding genetic diversity can give us an idea of a population's relative risk of extinction if they experience another big environmental change or threat. But you can have a population with low genetic diversity that manages to persist. Cheetahs, for example, have very low genetic diversity. But unless some new factor shows up and threatens Cheetah populations, they're doing fine. The genetic diversity on its own is not a factor determining their extinction or their survival. That's interesting. It's interesting to bring up Cheetahs because I teach that example in my class that they have amongst the lowest level of heterozygosity out there, especially within the cats, even their extremes of that. There's almost no genetic variability left in their population. And that's intriguing problem. You can graft the skin from one Cheetah to another, which suggests their immune systems are effectively clones that they don't recognize foreign tissue. At the same time, they're stable. They're relatively stable. There's no huge risk factor, except that they have very low fertility because some of those fixed mutations are affecting sperm motility. And there's as long as there's enough sperm moving around, they're OK. But I think they've lost about 85% of their sperm are malformed. And so you do have this potential fertility issue that's growing in that group. I think it's really important to remember that in populations with low genetic diversity, where the population size also becomes small, your probability of inbreeding increases. It's just more likely when you mate with another individual that you happen to be closely related to them. And that can lead to these fitness consequences that we call inbreeding depression. The thing that's important to remember is that inbreeding doesn't always lead to inbreeding depression. So we have cases where inbreeding is very high in a population, but there are no fitness implications that we can see from that. That population is still more vulnerable to new downstream changes in the environment because it doesn't have as much adaptive potential. But the inbreeding itself doesn't have to be a threat. Oh, absolutely. We see that in things like agriculture, where there are pure breeding lines of plants and animals, which have virtually no genetic variability, but are also quite healthy. We've effectively bred out all the bad alleles. And what you're left with is actually a relatively fit population. It may be susceptible, but it's also fit. So what is it that makes a population something we would call an at-risk population? How would you evaluate evaluating the profiles in a conservation sense, label something as at-risk? Risk in populations from a conservation point of view is usually about population size, and that connects to the population's genetic diversity. But there's a step that happens before we worry about the genetics. So we would consider a population to be at risk if it is either declining quickly or very, very small or restricted to a very, very small area where you basically have all of your individuals in one place where something bad could happen and might fall out. And the problem with small populations is that they're really vulnerable to any small changes in mortality rate or in birth rate. And there's these two processes that affect small populations more strongly than big ones. One of them is called demographic stochasticity. It's basically the idea that the death of one individual in a large population isn't a big deal. It might be sad, but it's not going to affect population growth, whereas if you have only 10 individuals left and one of them dies, you're suddenly down to 90% of the previous population size, the impact is much larger. The other process is environmental stochasticity, which is basically the idea that if you have a small, small population that's isolated in one particular place and something like a hurricane comes along, it's more likely to affect alert proportion of that population than if the hurricane hits a population that's spread out of our large area. And in both cases, these processes can contribute to what's called an extinction vortex where the population keeps getting smaller and smaller and smaller as each new mortality has a bigger impact on that decline population. Where genetics comes into play here is that as the population gets smaller, you also have a higher chance of losing genetic diversity over time. Genetic diversity has lost much more quickly from small populations than from big ones. And that decreases the ability to adapt to new changes over time. And also that you have a higher chance of inbreeding. Again, you have a higher chance. But if you find a mate that mate is closely related to you and although inbreeding on its own is not risky, as inbreeding increases, so does the chance of inbreeding depression, which is that reduction in fitness as genetic diversity decreases. OK, so I know the extinction vortex idea that every new generation with an effectively smaller population is at more risk of being small and getting smaller again. What about large populations that are genetically small or have what we call small effective population sizes? You can have enormous populations that are highly at risk. This may be a point where we're differing a bit in our definitions of risk. If a population is truly enormous, I probably wouldn't consider it at high risk. Unless it's a species that undergoes really dramatic fluctuations in its population size. So some amphibians do this, right? You can have explosive breeding amphibian populations where we have a small number of mature breeders, but after they've reproduced, they produce so many offspring at once that the population suddenly balloons. But then you have high juvenile mortality and the population shrinks again to a smaller number of mature breeders. I would consider those populations to be at risk. If the number of mature breeders is below a threshold where we think that there might be a high chance of extinction in the near future, and that would be a case where you would have a small effective population size relative to the actual population size, and maybe there's a conservation concern. But in cases where a population has recently declined due to some mass mortality events, say, let's take-- ooh, American bison, right? Which were hunted almost to extinction intentionally as part of colonization of North America. and only a few bison were remaining. The bison that are now roaming in North America or that are on bison farms in North America are all descendants of that small cluster bison that survived those massacres. So the effective population size in that bison metapopulation is fairly low relative to the number of individuals that are out there, but because there are now a large number of bison on the landscape, I wouldn't consider them as at risk as they were before. Because in this case, the diversity is lower, but the number of reproducing individuals has increased to a point where although they're not out like they're not in the clear yet, they're on an upper trajectory. I suppose the other thing that comes involved there is our personal human interest in their maintenance. So things that are of significant cultural interest that are cut and cuddly tend to receive the focus of our efforts in recovery of populations. Even if they're small, they're less at risk because of our interest in their preservation, whereas if it was a group of nematodes, it's unlikely that anybody would go out and try to preserve them. The one I'm thinking of that I think is really interesting in that context is the bulimipine discovered in a secret location that is concealed in Australia and probably existing since the time of the dinosaurs. It was down to probably a very small number of trees, and now is often joked about as being the least likely tree to ever go extinct because it is of such interest. It's in every zoological garden and biological garden out there as an example of something that almost went extinct. And so its maintenance is almost assured on those grounds alone as now an ornamental. So our own interest in a species can make it at risk or not at risk. Another great example of that is Toromiro tree, which was the endemic to Easter Island, and is extinct in the wild, although it is still present in botanical gardens around the world. The ways then to use genetic methods to look at past events to try and understand why a population is small or effectively small with a small number of breeding individuals. Can we use those same tools to basically see their past? I think that diving too much into what's happened in the past is super interesting, but I am going to be difficult to argue that it's not particularly useful for conservation actually. Okay, explain why. I don't generally disagree with you on these things. So I don't necessarily know that I do disagree with you on this. I just want to know why. I think it's an interesting point. We can use genetic and genomic methods to look at how populations have changed in the past and especially to look at large changes in population size in either direction. And those tools are really interesting and understanding the past demographic history populations is fascinating. I'm not convinced that it's of much use for the applied conservation of existing populations. The reason being that although we can see where a population has changed in size, we can't definitively link that to a particular cause. If we're looking at events, you know, many, many generations are potentially even hundreds or thousands of years in the past, there's no way to be certain that a correlation with a particular environmental change is what actually caused the population to change in size. And so there's always going to be some amount of speculation. And then looking ahead, which is what we're trying to do in conservation science because we're trying to actually recover endangered populations. If we look ahead, knowing what happened 300 years ago isn't necessarily helping us to boost population sizes now. So although those questions are really interesting, I'm not sure how well they relate to applied conservation. That said, one place where it's really important to be able to look at evolutionary history is when we define meaningful units for conservation. So for example, in the United States, under the United States and Dangerous Species Act, you can define what's called an evolutionarily significant unit that is subspecific. So within a species, you can have multiple ESUs or evolutionarily significant units. And in Canada, we have a similar process where we define what are called designateable units or DUs under the Canadian Species at Risk Act. And those DUs are then assessed to determine whether they are endangered or threatened or special concern or not at risk. And because our definitions of conservation status depend in part on the size of a population or the size of the number of species that are found in Canada, the way we define the DU really matters. Because if you split a species in its Canadian range into many, many, many different designateable units, they're more likely to be below the threshold for concern and be listed as endangered or threatened, whereas if you assess the whole species across its Canadian range, you're just more likely to have more individuals there in the first place. The two criteria for defining DUs in Canada are first whether the different DUs within the species are discrete from one another. So gene flow is either very, very low or they're not exchanging genes currently. And second, whether those two groups are evolutionarily significant from each other. And one of the ways you can determine whether they're evolutionarily significant is to look at, for example, whether they're on different mitochondrial lineages, which gives us a way to infer that they've been on different evolutionary trajectories for a meaningful amount of time. And that we think maybe there's likely to be local adaptation to different conditions that is important and that we want to preserve. You may correct me because this is your field of not mine. But when something like the US Endangered Species Act was first created, my understanding was it was created with the idea that it was out to preserve species. And therefore, but it lacked a definition of what it meant by species. And it ended up with these contradictory scenarios where something that was at risk couldn't be preserved because it was of unknown origin, potentially even hybrid origin. And in other cases where things that were what you would call an evolutionary significant unit didn't qualify because the species was what was being as effectively assessed. And so a number of things that I think, if I understand it correctly, actually went extinct while the debate was going on. That what was it we were out to conserve, units, species, hybrids, lineages, what was the thing of interest in the process, a couple of things went extinct while waiting. Is that correct description sort of the origin of the debate? I think that's a really good brief history of the origin of the debate. And I think that the introduction of the ESU or the DU framework is an attempt to recognize in policy that biodiversity is not always constrained to just diversity at the species level, right? That there is meaningful diversity below that level that we also want to acknowledge and protect. Where it gets really messy is that we're sometimes challenged to define the boundaries between species. And when we start to try and define the boundaries below the species level, things get even more clear and we can get into these real philosophical wormholes. My friend Arnemore is at SFU calls them bits of biodiversity or bobs because it just it becomes it becomes almost ridiculous if you if you carry some of the logic used to define ESU or DUs to their logical conclusion, it becomes unclear what we're even trying to do. And I think that that's not that's not indicating confusion in the intentions, but just confusion in the difficulty of translating science into policy in some cases. I think it reflects the fact that what we're trying to do when we assess the species and we have to define a meaningful unit is that we're actually trying to put a square peg into a round hole because diversity exists across a beautiful spectrum. That's the whole point, right? Caribou and Yukon are different from Caribou and Quebec, but where we draw that line where we want to see a clear line, you know, evolutionary processes are creating this beautiful rainbow spectrum instead. And so it's very hard to translate that into the kinds of discrete boxes that policymakers like to see. I think that's a really good explanation, but that it's not necessarily a problem with the policy or the intent, but in trying to make something that is effectively an ongoing and ever changing process into something that is quantifiable, which is tricky. And I think the other thing to point out is that these political acts like the Species at Risk Act predate the existence of widespread tools like DNA to measure things like gene flow and to easily quantify borders in that sense, easily being a very in quotations word at that point because it's not easy, but but it was easy at the time to talk about species because there was less debate to a certain extent about what a species was. And now that we are uncovering with tools like genetics, the accelerating discovery of limits and unusual sources of gene flow or hybridization, which appears to be on the increase in reality and or we're better at detecting it than we ever were before. It begins to question some of those previously well-defined units and what their status might actually be. That's been a challenge in the case of designateable units in Canada because as we collect more genetic data, some of the previously defined designateable units turn out to be inconsistent with what the genetic data tell us. And again, that's not a failing of anyone involved in that process, right? We always make those assessments based on the best available data at the time. And then the data change and maybe we need to reassess where we draw those lines. But that is a real challenge because defining a conservation unit is the first step to being able to protect it, whatever you call it. It's the first step to deciding what number of individuals you're considering in your assessment. So whether it turns out to be threatened or endangered, it's the first step in deciding where any applicable policy will be implemented. You know, it matters how we define these things, but we still haven't agreed on what we're even trying to define. And I think we should point out at this point that this can have extremely real world consequences. So whether or not a protected species or a designated unit is in an area, can have consequences in terms of whether or not that area can be developed in an economic sense, whether it requires different kinds of protection, whether it can be opened for hunting or exploitation in other ways, those come down to legal challenges, which often rely on this science that we're still struggling to even define. And at the legal level or at the level of whether or not a permit should be issued for whatever activity is being applied for, that requires a sort of yes, no answer. And unfortunately, the boundaries that we want to apply to different conservation units are not yes, no answers most of the time. And so there's an inherent conflict between a system that requires explicit data and a scientific exploration that knows that boundaries are very gray. And I agree with everything you just said, except for the unfortunately, because that rainbow spectrum of diversity that's out there is actually a positive thing, but we're constrained by the system that wants to protect it in discrete boxes one at a time. And those two systems just don't match up. How do these various acts treat the presence of hybrids? If the hybridization is between two species that are recognized, native, and considered to be at risk, then I think there would be a space to consider the hybrids as a natural part of that system and still receive protection. Although, I think it would probably come down to a case by case basis. But if I think, if I think, for example, about, I can think of a hybrid system where that maybe will answer your questions. So in Canada, in Ontario on the North Shore of Lake Erie, there is the Canadian population of Fowler's Toad. And Fowler's Toad is widespread and fairly abundant in the northeastern United States. But in Canada, it's only found in these three locations on the North Shore of Lake Erie. And those locations are isolated from one another. So we have these tiny populations of Fowler's Toads, just kind of eking out in existence in these coastal marshes. Fowler's Toad can hybridize with American Toad, which are common and not at risk in Canada. And they do hybridize with American Toad. And so when you do surveys for Fowler's Toad, you find Fowler's Toads, American Toads, and hybrids. In Canada, assesses Fowler's Toads in Canada. They are considering the number of Fowler's Toad that are present, knowing that there are also these hybrids present formed by a hybridization between American and Fowler's Toads in that they're dispart of that system. But that hasn't limited protection for the Fowler's Toad. Okay, let's go back to then. Can you give me something from your own research, something that you actually work on, and how you're using conservation tools or genetic tools in conservation to deal with it? One topic where I've used genomic tools to try and understand how populations are responding to rapid threats and how we can most effectively work to recover them is in work on bats and white nose syndrome, which is a fungal infection of bats that was introduced to North America in or just before 2006. And it was introduced either in or near New York State and first observed in hybrination sites in New York State. And with the biologists, their observed was sort of fuzzy white growth on the noses of hibernating bats and then severe mortality of bats near the end of hibernation. And this started a whole cluster of studies and collaborations and a really impressive interagency, interlab transnational effort to try and understand what was happening. That fungal disease spread across North America and it spread up into Canada and down into the western states. And it is now up as far as Alberta and Washington State and is expected to move into British Columbia and up into Yukon and Northwest Territory shortly. So as that fungal disease moved across North America, it caused 95% collapses in populations of some species, including the little brown bat, which had previously been one of the most common mammal species in North America. So this is the largest documented decline in the mammal species ever. That's a huge drop in numbers. And part of the reason that we think that bats are surviving and coming out the other side of white nose syndrome or that we think it affected species are coming out the other side of this huge decline is because there were so many of them in the first place. So they had that very high genetic diversity and high standing genetic variation that meant that there was adaptive potential to this new threat. What I worked on during my postdoctoral research is this question of, okay, if 95% of the bats survive, is there something different about those survivors? Are we just waiting for those survivors to eventually become infected and also die? So we're just watching a very slow extinction process play out. Or is there something different about those 5% that allowed them to survive that might actually be a trait that's heritable that they could pass on to their pups? And the reason that this is important beyond just academic curiosity is that in the first scenario, we would want to try and prevent future infections. We'd want to try and intervene as quickly as possible, take some individuals into captivity, work on treatments. In the second scenario, we're talking about basically a real time selective sweep in which the individuals coming out the other end are probably taller, interresistant. And that scenario though, we would want to leave it alone and let that process play out and not interfere with it. And then work to support the recovery of that population, which is not going to be a question about disease anymore, but rather a question about increasing pups survival, right, and boosting population growth. And so the first thing that we did is we compared immunogenic diversity in sample taken from bats, little brown bats, before the arrival of white nose syndrome in Manitoba, Ontario, and the maritime provinces. And we looked at how much diversity was there and which of theals were most common. And then we also, we ran the same assay on a sample of bats that died during that peak in mortality. And our question was whether the two matched up or not. And we found that in fact, they didn't. It was a non-random sample of the pre-white nose syndrome average that ended up dying during that mass mortality event. And so now working on follow-up work with survivors, expecting to find the same thing in the opposite direction. There's been other work that has also come out since then, some of it led by Georgia O'Terry, looking at immunogens in surviving bats and finding that they're different than the average before this mass mortality event. So now that we know that this selective sweep was successful, essentially, and the bats that have come out of the other end are tolerant or resistant to the disease, that's a heritable trait they can pass it on to their pups. And that means that the most effective conservation tools will have nothing to do with genetics and are all about protecting bad habitat, both during the winter and also during the summer months, and supporting high pups survival, making sure there's enough insect prey for them to eat, making sure that they have safe maternity roofs to raise their pups in, and that that will help the population to recover over the long term. Okay, so you would advocate then a effectively a mixed approach where we can use the sort of molecular tools we have to understand what is happening, and then switch to a strategy which effectively uses that information to inform decision-making on a practical level, which might be in some cases trying to preserve particular populations, but in other cases maybe understanding which individuals are more likely to be successful if we provide that level of intervention. Yes, exactly, and I think it's important to remember that genetics is a great tool for understanding what is going on, but it is almost never the tool that will actually conserve a population. It can provide the background information that we need for adaptive management strategies, and that's really important, right? When we try and conserve a population and we take action on the ground, we want to evaluate how well that's working, and genetics is a great tool for doing that, but all of it needs to translate into on the ground action before it becomes applied conservation. If I can loop this back then to my course that I sort of designed for, which is an evolutionary biology, are the bats in that scenario a good example where a standing crop of variation allowed effectively certain individuals to be resistant to a novel infection? Is that exactly the scenario we're always talking about when we talk about the necessity of having variable populations? Yeah, that's exactly right. little brown bats and the the arrival of white nose syndrome, they are the poster child for maintaining common species as common, maintaining large populations of as many species as possible, and putting efforts into conservation that will protect common species as well as endangered ones. Okay, I quite like that. I hadn't thought about them as being such a perfect example of. Oh yeah, no, they're that they are the poster child. They are it. That's the thing we've always talked about that happened in front of all of us. Yeah, and the flip side of that is although that 5% came through and we're now seeing increases at the hibernation site that my team monitors, which is really exciting, those those tolerance resistant bats are coming out the other side of a severe population bottleneck where genetic diversity is reduced and not just by the bottleneck, but also by this strong selective suite for particular genetic variants, right, and therefore for the other alleles that are linked to those. And as a result, that population is now less likely to contain whichever alleles are going to be, you know, useful as the next unpredictable pathogen shows up or potentially under scenarios of climate change. So they're very active survival. Now potentially classifies them as a new at risk population. Yes, potentially. That's right, they've lost that advantage. Interesting. It's almost like a one-off survival strategy, whether it whether they rebuild or become hit by the next big thing is an unknown at this point. One one thing that gives me hope on that front is the fact that the bats that co-volved with the fungus that causes white no syndrome in Europe are apparently doing very well. They are threatened by all the things that wildlife is threatened by across the planet, right, habitat loss and climate change. And but there are many many species of bat in Europe that can tolerate or resist infection with white no syndrome over the winter because they also would be the descendants of the survivors of whatever bottleneck may have happened. Something I sometimes find frustrating about conservation genetics is that it's it's one of those fields where a little bit of understanding can be dangerous if it becomes dogmatic. So we learn that, you know, in bread populations have a higher chance of extinction and that's true. And we learn that very small populations have a low probability of persistence over time and that's true. But sometimes that gets translated into the idea that those populations are not worth recovery efforts. And so I just want to share a really quick story about some work that I had the chance to do on the island of Mauritius, which was the home of the dodo. Then Mauritius, if you're only familiar with the dodo, is a small island nation in the middle of the Indian Ocean. So if you picture Africa and then move east to Madagascar and then continue quite a ways into the Indian Ocean, there's a little island there. That's Mauritius. And so the work that I got to do there was with the Mauritian Wildlife Foundation, which has been working to recover a number of bird and reptile species that managed not to go extinct at the same time that the dodo was eradicated. One of those was the Mauritius Kestrel, which is a small Kestrel, so it's like a very small raptor. And it declined dramatically in the 1970s due to the application of DDAT, which affected at quality and their first survival of chicks and that success. The reason I'm sharing this story is that that population declined to four individuals, which is well beyond the point that conservation genetics dogma and conservation dogma in general says is too small. It's not enough, right? It's don't waste your resources. We can't bring them back. But an effort was put together to recover that species. They were taken into captivity. An intensive captive breeding program was started. And there are now wild Kestrels flying around in Mauritius again. And they are all the descendants of those birds that were taken into captivity. Are they very, very inbred? Yes, yes they are. If there have been some consequences from that, yep, you can document some impacts of inbreeding depression on those birds, but they're still there and they're still flying around. They were reintroduced. They're not extinct. The population increases and decreases. There are rough patches where more interventions are needed than there are good patches. In the good patches, genetic variation slowly increases over time. And so I just wanted to make sure that we also discuss the fact that when we calculate probabilities of persistence or extinction and how those change with genetic diversity, we are just calculating probabilities, a probability of what might happen if we roll the dice. But we don't get to know if we're on those many, many scenarios that go to extinction. Or if we're on one of the ones that actually persists and maybe over evolutionary time, it gives rise to a new species. And so I wanted to make that point to about how sometimes this information gets. It becomes dogmatic and can be a real limit to what we think is possible. And there's also cases where we can judge a population to be stable and fine and come back to discover it banished. Absolutely. The last question I always ask everybody is how did you end up being a professor in a university? And I know for a fact that your route to that was not a linear one. How did you end up in this position? Do you always assume that you were going to end as a conservation biologist in university or did you have other plans? I knew that I wanted to work in wildlife conservation. And that has always been my plan. But there are many ways to do that. And there are many ways to do that and have impact and create meaningful change. And so I wasn't set on a particular version of that. Also the job market was problematic at the time I was looking at it still is. And so I knew that I might not really be able to decide exactly where I wanted to land. So I did some work with some non-governmental organizations that work in conservation science in between my degrees. And I did masters studying bad habitat use. And then I did a training program at the Jersey Zoo in the UK where I also got a graduate certificate in endangered species management from the University of Kent. And had the chance to do this work with the Meritian Wildlife Foundation, which was really a game changer for me in terms of what I felt was possible in conservation science and the kind of impact that I wanted to have with my work. I went back to school and did a PhD at the Royal Entry Museum at the University of Toronto and studied turtle conservation genetics. And this was actually the first time that I worked in genetics at all. My undergraduate and graduate work and master's work, sorry, had nothing to do with genetics fairly intentionally. By during that certificate in endangered species management, I started to think more about how genetic tools could help me reach my goal. And so I, you know, rethought my priorities and used genetic methods during my PhD. And during my postdoctoral research on bats and weight nose syndrome. And then I ended up in a position as a research scientist with the Ministry of Natural Resources and Forestry in Ontario, which was in some ways my absolute dream job. Because government science positions provide an opportunity to really tailor your research to meet direct needs that policymakers have or are likely to have in the near future and to translate those results to the people who can actually use them. So where there are certainly cases where people working in academic situations want to be able to get their work into the hands of policymakers. It's not always easy to do that from university context. And when you're working directly in the government to do your science, it's much more straightforward. That pipeline is much more clear. And so, so that was wonderful for a while. And then I took a position at Carlton University in the Department of Biology and Moved My Lab there. And I'm now working to understand how to have the same kind of impact that I had in my government science position from this new position with the bonus that I get to teach again. And that makes my heart really happy. And with that, I'd like to thank Professor Christina Davy, who I've known since we were students. And I think I've helped out on some of those field trips once upon a time. Thanks for joining us on the BioAudio Podcast. Thanks for listening to the BioAudio Podcast. The BioAudio Project was started to provide free alternative to textbooks for students and educators to provide a more inclusive resource and one we can add new topics to at any time and modify. If you are a student and you have enjoyed this episode, send me a note on Twitter @Doctor_Bat underscoreGirl or on mastodon @ProfessorBatGirl at ecoevo.social and follow me to hear when new episodes are posted. 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