[0:00:00 Speaker 0] right, thanks jay for having me. And thanks to E. S. I. And thanks to you all too for coming tonight. I'm really excited for the opportunity to talk to you about three of my favorite things. Lemurs friends and of course power. So I am a biological anthropologist and biological anthropology is the study of humans within the context of living things. And in particular I'm a primatologist. That means that I focused my research on non human primates, our closest relatives. How many of you know what a primate is? Anybody? Can I know you said don't say anything, but this is the one time you can talk, who can name a primate for me? Call something out, aye aye aye, Lemurs monkeys. Excellent, excellent. You guys know what primates are? Wonderful. So um primates are the lemurs lorises there, tar Sears there, monkeys, They're apes these are our closest relatives. And as a primatologist I'm interested in their evolutionary relationships and the way we look at their evolutionary relationships. The way we show it is with a family tree like this. And so I'm gonna walk you through how to read this family tree. The first thing you'll see here is that monkeys and apes are closely connected and they're linked and that's because they are close relatives to each other and they share a common ancestor. Tar Sears share a common ancestor with the ancestors of monkeys and apes. Lemurs and lorises are closely related and they share a common ancestor and then the last common ancestor of lemurs and lorises share. A common ancestor with the last common ancestor of tar shears, monkeys and apes. And so this is the last common ancestor of all primates. And understanding this family tree is going to be important later in the talk, but it's important to know that humans are also on this family tree and we're most closely related to the apes. But I focus on lemurs, I'm interested in lemur behavior and you might wonder why in the world does someone in an anthropology department that's interested in humans? Why does someone studying anthropology department study lemurs? They seem very distantly related to us, but there's a very good reason to study lemurs besides, they're super interesting in and of themselves. But one of the reasons for setting them is because they have a very long independent evolutionary history separate from us. So they evolved, they they separated from the other primates millions and millions of years ago. And so lemurs are a great group of primates to test hypotheses about why humans have evolved the way they have. Great for testing hypotheses about primate evolution. So lemurs, this is a bunch of different kinds of lemurs. There's actually 103 different species of lemurs that are recognized today and they come in a variety of shapes and sizes from this little tiny mouse lemur here, which is about this big and this is a packet of sugar and the tiniest primate in the world weighs about the same as six packets of sugar. So mouse lemurs are really tiny but lemurs are also much larger. They can be um the about the size of about 10 £15. But you guys probably recognize these guys. The ring tailed lemurs are probably the most famous of the lemurs of all, but there's a lot of diversity and lemurs, lemurs are found in Madagascar and this is where Madagascar is and it looks tiny there. But that's just because africa is so huge. Madagascar is actually the fourth largest island in the world. And if you move it over here onto the U. S. You can see that it's actually a little bit larger than the size of California. So it's a really large island even though it looks small and it's about halfway around the world from here in Austin. So if I want to go do my research on lemurs, the first thing I have to do is I have to hop on a plane and fly about three hours to Atlanta. And then I fly about 10 more hours to Paris France. And then I fly on an 11 hour flight to Madagascar and then you have that's not even counting the time in the airports and you guys know how it is an airport. So we'll add about 12 hours of just time sitting around in airports and that's being very generous to the airlines, so that then gets me to the capital of Madagascar Antananarivo. So then I usually spend the night and get in the car and I have to drive about 15 more hours to get to more and of which is the closest town to my research site and then I spend the night by a bunch of supplies and I drive about four more hours to get to my site. But that's assuming that the roads are actually good condition and this is Madagascar and Madagascar is notorious for having terrible roads. So sometimes I just cannot go by road, in which case, because I have to drive through rivers and things like that. But if I can't go by road then what I have to do is I have to take a boat on the Mozambique channel for about three hours and I get to be a loser mayor, which is a fishing village nearby. And if I'm lucky I can hire an ox cart or to to be able to take me and my stuff to the station. This is failing in one of my graduate students And if I'm not lucky then I get to walk through the mud flats all the way to my site, in which case it takes me about 61 hours just to get to my site before I can set up my tent to be able to even start thinking about doing my research. So um it's quite a trek to get to Madagascar, but and it can be exhausting, but I have to say this is one of my favorite parts. I love that. One of the things about being a primatologist is I get to go on these adventures. And I've been working in Madagascar for about 23 years. I've worked in rainforests, I've worked in the spiny desert, I've worked with large lemurs, I've worked with small lemurs and for the last 10 years or so I have been focusing mainly on varosha, which is my main study species. And as jay said I set up a new field station in the caribbean matey national Park called Ankara Sifaka. And actually that's the region of the forest is called Ankara Sifaka. Which is really nice because it means the place where there are also shift back and so it's kind of nice that it already had that name. So I set up this field station in 2006 2007 and this is what it looks like. We have some buildings not super fancy but we have some buildings, we have solar power. So we have energy researchers sleep in a tent. I like to have a big one. We use the latrine, we eat beans and rice. It's pretty basic accommodations but it's really it has all the things that we need to be able to do, the kinds of scientific research that we want to do in the forest And I've got 82 km of trails into the forest and so that we don't get lost. I put up these little street signs here so that we can navigate around the forest. I have 14,000 trees marked and identified and then I have habituated 130 different shifts and you have to habituate the lemurs to human presence, especially if you're interested in social behavior like I am because you want to make sure that the animals are behaving in their normal way if you want to collect behavior on them Behavoural data. So and as I said, I'm interested in behavior and shift back are very social. They live in groups of 2 to 14 animals and they love to groom and play and things like that. They are our boil. They live in the trees and they eat leaves and buds and seeds. And one of the things that they really love to do is go try to get the leaves that are at the very tips of the branches. And so they have these wonderful adaptations for being able to feed on the terminal ends of branches. They sleep in really big trees at night. This is a baobab tree here. I don't know if you can see that's actually a little ball of lemurs right there and I call it a sleep ball, it's not a technical term, but it looks just like a ball of lemurs and they're huddled in the trees at night and you might wonder why in the world are they sleeping in this really tall tree? Well that's because of these guys, this is a fuchsia fuchsia is essentially a really big mongoose and they love to eat lemurs. And so the husa are able to hunt in the trees, they're very agile in the trees. And so the ship back if they want to sleep at night where they don't have to worry about being eaten by a fuchsia who can climb in the trees, they need to sleep in something really tall like this because the foods that cannot climb these giant baobab trees and in fact no one can not even, the, the way that the Shiva get to these trees is they have to jump from a neighboring tree into that tree. So it's a really safe place to be able to sleep at night, but you have to be a really good jumper to be able to make it into one of these trees and shrubs are amazing jumpers, they have this form of locomotion called vertical clinging and leaping. So a lot of monkeys walk around on their, you know, like a cat or a dog or you think about squirreling tree on all fours. Well, the ship, vertical cleaners and levers and what they do is they hold onto the tree, They push off turn 180° and then land on the next tree or they just bounce off like a ball in a pinball machine and go right to the next tree. So there are these amazing jumpers and to be able to do that, they have to have these really long, strong legs and because they have these really long legs when they come down to the ground, if they were to walk on all fours there behind would be up in the air and their head would be down in the ground so they can't walk like that. So they walk around on two legs, but they don't walk like you and me, they do this hopping motion along the ground. And I have some video for you. They love to this is they love to use our trails. And so they are super fast. It looks like there's these little tiny about the size of a cat and yet they can go faster than me down these trails. Okay, so Shiva and have one infant every year too. And they start having infants when the females are about five years of age. And a lot of my work has or some of my work has been looking at things like how does food availability influence the ability of females to have infants and the survival of infants. But what I want to talk to you about is how this form of locomotion actually influences how they carry and nurse their infants. So what happens when a baby is born, the female starts carrying it in the nook of their kind of in the thigh area here and when the baby matures after about several weeks, the baby will move on to the back. This is a much older baby here, but they move on to the back. But um when when you think about the way a human, like if a mother is wanting to walk around and carry her baby or if a monkey is wanting to walk around and carry the baby, the mother can actually move around and carry their baby while it's nursing. But um the ship to have a problem and that they are vertical cleaners and lepers and most primates, the nipples of the female are on the chest, right at the very front. And so this works out fine most of the time. But if you're a vertical cleaner and leaper, think about what happens to the baby's head. If the mom is holding onto a branch, turns around, jumps off the tree and lands on another tree, what's going to happen to that baby's head? It's going to get smashed right. Not really good. If you want to increase your fitness, moms don't really want to kill their babies while they're jumping around. At least they shouldn't. So you'll notice here this is actually Augie here who's nursing on his mom anna and you'll notice that Augie is actually his faces in her armpits and I think she back are a great example of natural selection because you can see how, if a female has the nipples on the front of her chest and she uses vertical clean uh, and leaping motion, locomotion, then it's not great for fitness, but you can see how a female who had nipples that were a little bit farther to the side of her chest. Her babies would be more likely to survive. And so over evolutionary time, over millions of years, the nipples have migrated to the armpits and babies are able to survive. So a great example of natural selection. So who here has seen the Madagascar movies? Yeah. Have you seen all three of them? The third one is kind of crazy, but it's really good. Right? I love the Madagascar movies but they don't have any ship takin them. Can you believe that they made a whole movie and they didn't about lemurs and they didn't put any shift but never don't worry. Sivak had their time of fame And that they were in this movie by Disney called Dinosaur about 15 years ago. And contrary to Disney, I hate to tell you. But the fact we're not around during the cretaceous period with the dinosaurs. And the other thing that Disney did with this movie is they set up the the the ship fox social group as a family group, a male and a father and a mother and a kid and the father, they made larger than the mother and he was the one who kind of ran the show. But that's actually not the way it is with shift back here is a graph that shows you the wait for for Shiva. Um for females and males this circle here is the average weight for females and the average weight for males. And the lines here are, they're a statistical measure of variation called standard deviation. And so what you can see is that females are actually larger than the males. So Disney got that part wrong, right. And the other thing they got wrong is that females run the show. In fact, females are what's called, or what's called female dominant. And I'm going to give you a typical example example of a typical day for a male, she faq in the wild. So here's rich and he's eating a seed pod. These seed pods are kind of rare in the forest. So he's really excited about it. And Emily's hanging out nearby. Emily looks to see what he's eating and decides she really wants it. So what does she do? She hits him on the head and she takes it and then she goes off and she eats it by herself and I don't recommend doing that. And it's not very nice behavior, but that's, that's typical of fox societies. If females want something, they get it. So in some ways she fog are like wonder woman and that they have superpowers or at least they're super jumpers like wonder woman and females have a lot of power. And given that when I was six years old, I wanted to be wonder woman. It's not surprising that that I actually study female power in an animal that has amazing leaping abilities. So anyway, before I tell you about some of my research on she's like I want to start out by talking a little bit about the science of setting the lemurs. And so um the first thing we have to do if you want to study the behavior of wild lemurs is you have to find them because they're living in the forest and you have to figure out where they are. So we use something called radio telemetry and so we put a put a radio collar on him, this is Isaac here and he's got a radio collar on. And then what we do is we use something we use a receiver and antenna and it picks up a signal that's being put off sent by the radio collars and were able to locate where they are in the forest. But to be able to put that radio collar on the lemur, I have to actually capture it first and I don't capture the lemurs myself. What I do is I hire an alpha Nafta is an amazing darter. He has darted lemurs with a blow pipe for about four decades. He started thousands and thousands of lemurs. He works with people primatologist such as myself all over the island. And so I hire him because he's just amazing. Remember those little mouse lemurs I told you about, they're about this big, he uses a blowgun to dart them at night. He is so incredible. And so I hire him instead of doing it myself. And what we do is I bring him in and we're out there and I'm like okay enough I want you to dart this lemur here. And so he just pulls out the blow pipe, shoots a dart the dark lands right in the thigh or buttocks, muscle injects the anesthetic. The lemur gets a little bit wiggly and we run under immediately with a bedsheet and catch it when it falls out of the tree. And then that allows me to do things like put a radio collar on or stuff it in a basket so I can see how much it weighs. So um but while they're down and while they're sedated I go ahead and take a lot of measurements and samples from them. You'll see here that you see some some holes in the ears. One of the things that I do is I want to get a DNA sample. And so I take a little bit of ear tissue to get that D. N. A. It's like when you get your ears pierced it's just a little punch and that allows me to be able to get some genetic material but I'm actually I've been collaborating with Tony de Fiori who's in the audience here. Um One of the faculty at U. T. With me. And we've been collecting fecal samples and we've figured out how to extract a DNA from the fecal samples. So pretty soon I don't have to put holes in their ears anymore. What we're going to be able to do is collect genetic samples non invasively. But while they're down some of them get a radio collar but the other ones get a dog collar and tag so I can identify who they are easily. But we also do things like look and see how many ticks or lice or things like that that they have. And I collaborate with researchers like this is Phoebe here who's a wildlife veterinarian. And with Fiji we've been looking at things like how many white blood cells to normal healthy she has. What is the normal weight, the heart rate, What is the blood pressure, what does a normal healthy look like? We don't know unless you collect a lot of data from wild animals to see what it's like. So I collaborate with feeding on that sort of thing. But really what I'm mostly interested is understanding their behavior and the way I collect the behavioral data is I spend a lot of time looking up in the trees and so by the end of the field season my neck is really strong and we just write down in a systematic way what they do and luckily the ship take a siesta midday they're very civilized and so that gives me a chance to sit down and get off my feet for a moment. But I don't actually rest in terms of stopping to work. This is the time during the siesta when I see some of the most interesting social behavior. Because this is when they're having little fights about who gets to cuddle with who and their grooming each other and they're moving around and displacing each other. And so even though I get to sit down, I don't get to relax during the siesta. But I'm a professor here at U. T. And so I have to teach. I don't have I get to teach classes. I get to teach classes in the fall and spring semester. And so I can't be there in Madagascar collecting data but I need to have data year round to understand their social relationships. So I have a team of people who work with me on this project. I have local assistance. I have both us and Malagasy graduate students as well as volunteers who are there day in and day out collecting the data and sometimes I have to wonder who is actually observing whom. So but physiology influences behavior and um you may have noticed hormones influencing behavior especially in certain times in your life when hormones are in fluctuations such as when you're when you're a teen that you are were a teenager or during pregnancy when hormones are changing. That's when we really noticed how our mood and behavior is influenced by hormones But its influence on a daily basis by these hormones. And so if you're interested in understanding how hormones influence behavior and you're studying humans, you can just go up to the person and say excuse me, will you spit or pee in this cup here? Or can I get a little bit of blood from you right after you've been stressed. So I can see what your hormones are like. But I can't go up to my lemurs and say excuse me, will you spit in this cup for me or will you present your arms so I can get a little bit of blood. I can't do that. But what I can do is take advantage of the fact that they do urinate throughout the day periodically and I can try to collect it opportunistically. And so I just started collecting urine. And so I talked to a colleague of mine that I'm collaborating with and I said how do you collect the urine? Because she works with lemurs and her lemurs are quadra pedal. And so they stand on the branch and and she says I just stand underneath with a frisbee and I catch it when it comes down and I thought I can do that. That's not too hard. Right? So I went and I thought, okay, here's the lemurs tail goes up. So I rushed underneath with my frisbee. And this is what I got. I don't know if you can see there are a few little drops of urine here, there's actually some pellets of poop as well. But mostly what happened is the german all over my face. The reason I couldn't use this system is because they're vertical cleaners and sleepers. So when my lemurs urinate, it went up against the tree and splashed everywhere and that's why I got all over me. So I don't use that method. I don't really like getting it all over my face. But so what I've done is I've developed a new system of collecting the urine and instead what I do is when I see that tail go up, I rush underneath them, put tinfoil all around the bottom of the tree. You see why it's important to have animals habituated because I don't want to scare them during this time. So I run underneath, I put the tinfoil around and hope that they don't switch trees before they, before the ap. And I also hope that if they do that, it actually lands on the tinfoil. But then once it does, I can use a pipette and collect it, put it in a vial and then stick it in some liquid nitrogen to store it to send it off for analysis. That's a lot of work to get a little sample. So luckily some hormones you can actually get from fecal samples. So, um I also collect poop while I'm there. And so what I do is I collect the fecal sample, wrap it up in some tin foil and a little package, stick it in the oven at 175°F for about three hours. And then I can ship it off to the lab and find out things like dominant males have higher testosterone than subordinate males. So I'm interested in social relationships, but I can't give my lemurs a survey or do some interviews and ask them who are your friends, who do you consider family? I can't ask those kinds of things. So if I want to know who are the friends, who are the family, I have to go around collecting these kinds of data and then try to piece together the puzzle of what their social relationships really are. And one of the things that fascinates me about social relationships is power. So when people talk about power and animals, they usually talk about whose biggest and baddest the fighting ability. We even use terms like brute force, right? So when people think about power and non humans, they tend to think about fighting ability. But power can be more than fighting ability because power arises whenever there's an inequality in a relationship. And that inequality that social inequality can arise because of an asymmetry in resources or coalition partners or knowledge. And um mating, sorry, mating opportunities and sex ratios can also be a source of power in relationships between males and females. And I'm interested in primate social relationships and primate the power and primate societies. And so what I want to know is when is power based upon force or the threat of force and when is power based on more economic sources of power? When is it based on an asymmetry other than just fighting ability? When do animals have leverage? And also I want to know what is it good for you have this power? What is it good for? And in human societies, people sometimes use power for fame and fortune, but the lemurs don't have money so they're not going for fame and fortune. But the currency of biology is fitness. And so what I want, what I want to look for is and see do individuals who have more power, do they have higher fitness? Do they pass on their genes to the next generation more than other individuals? So I can look at questions like who has babies? Do those individuals who have babies, do they survive? And do the babies of do those babies grow up and have babies of their own? That gives me information about fitness. But I also can look and see who wins conflicts? Who gets the food because that's going to increase if you get food that's really important for producing these babies. And then I can look at things like do winners of conflicts actually have more babies? So if you want to see a conflict, in fact the best place to do, it isn't a baobab tree and I don't know how much, you know about bail bob's, but here's a baobab fruit and the really want to get at these seeds here in the fruits and the seeds are full of fat, the really fatty and it's so the seeds are so fat that you can actually go on amazon and buy baobab oil in the health or beauty supply section because there's so much fat and so it's a really great source of nutrition for the lemurs. But the problem is that there's this really thick hard shell that the fruit has to protect those seeds because they don't want the lemurs eating them. And so she has to spend a lot of time, it's really hard to break through those that shell and most of the time they're not successful, they'll spend a lot of time just trying and trying and trying to break through with their teeth. And then these are some of the fruits that they just dropped down on the ground because they couldn't get through that hard shell and dominant animals are pretty cheeky and what they like to do is they like to wait till somebody gets one open. They break through the hard shell and then the dominant individual comes along and takes it says thank you very much and they don't have to spend the energy trying to break through. And so here's an example here you have zipper who's working really hard on that baobab fruit? And you've got savannah just hanging out down here waiting. And so one zipper finally breaks through that hard shell savannah comes along and takes it away. So that's what it's like in a shoebox society. Not always fair, but so I can look at questions like do individuals who win these conflicts? Do they have more babies? And do their infants survive? In other words, does winning translate into higher fitness? And so this figure shows infant survival for dominant females, subordinate females and females who are the only adult female in their social group. And you'll see that winning doesn't, you know, if you're a dominant individual and you win your conflicts, that doesn't necessarily mean that your babies are more likely to survive. So this is contrary to my hypothesis and it's contrary to expectations because it seems pretty intuitive that somebody who is more powerful should probably, and has better access to resources that their kids would do better and they would have higher fitness. But this is what I love about science you get, sometimes you get these surprising results and when you get these surprising results, it's like a really cool puzzle. And now, so I've got this thing that's not expected. I've got these data and I'm sure it's showing something I don't expect. So now I get to go like a detective and trying to figure out why in the world did I not find the expected result? Was there something wrong with my hypothesis? Is that did I is there something about the way I analyze the data? Maybe I need to look around and try different explanations, trying to figure out what is going on. And this is what's exciting about science. If you love puzzles and I love puzzles, if you love puzzles, science is a great career for you. So um but remember she facts are what's called female dominant and that means females rank above the males and they basically get what they want. And that's why I actually started studying shift because I was interested in the evolution of power between the sexes. And so there are some different hypotheses for why female dominance might evolve. And one of the hypotheses is that you're going to see female dominance arise whenever animals live in really harsh and unpredictable environments. Madagascar gets hit by a lot of cyclones and that makes it a very unpredictable environment for females. In terms of reproduction, they don't know whether food is going to be around or not because the cyclone might come and destroy their habitat. And so the hypothesis is that females need priority of access to resources when they live in these really unpredictable environments. And so how do they get the priority of access to those resources? The hypothesis is they mate with wimpy males. So the hypothesis is that females like deferential males and that females have dominance because females have made it with males who give them the good food, they go, oh I don't need this food, you take it, you have it, I don't need it. That is the idea behind the male difference hypothesis, wimpy males. And so if this wimpy male hypothesis is true, then we might predict that males just give the food to females and they don't make much of a fuss about it when they give over the food. Right? So let's look at some data. So this is submission rates here. This is how much the males are some being submissive to the females. And the way of blackmail is our way of life in general is submissive. They don't do this bow down like like we might do in human societies, they make something called a chatter. And so what I can do is look and see when do males just go, you take the food and when do they actually put up a fight? And so what you can see is males are not spontaneously giving up the food and going, you take the food. Not very often most of the time. The reason males are submissive because the females are beating him across the head. So so this example here I gave the example of baobab fruits, a classic example in my mind of what's really going on in chibok societies, you see with the baobab fruits where the males will be working on those fruits for maybe even half an hour trying really hard to break through that hard shell. And when they finally do, the female comes along and cuff them and they hold on and they just chatter and the females cuffing them and hitting them and going no give me this fruit and they don't want to let go and eventually they may, or sometimes they even keep holding onto this fruit and chattering while the females eating it. And so in my mind, that just really goes against this hypothesis of wimpy males who just give up the food willingly to females. Right? So this hypothesis just isn't supported by the data. But there's another problem with this hypothesis, I don't know if you picked up on the wording of this hypothesis. This hypothesis phrases it as if the males had the power in the first place. And so it's been seen as an evolutionary puzzle why in the world when the males give up their power to females. And so if you'll recall, I showed you this figure earlier, females are actually larger than males. And so why would we expect smaller males to be more powerful than the females? And another question is, did males actually have the power in the first place? And so what I wanted to do is I wanted to look and see, what did the last common ancestor of primates look like? Did the last common ancestor of primates, were they male dominant? And so what I did is I teamed up with some paleontologists and we took advantage of some tools that paleontologists used to try to reconstruct what was going on with their fossils. And so the way you do that is you look at a trait across all these living primates. And then from that, you can reconstruct what that ancestral primate probably looked like. And so we did that with dominance and power. We looked to see what did the last common ancestor of primates look like? Well, no, the last common ancestor of primates was not necessarily male dominant. Our results showed that actually there's a 50% chance that the last common ancestor of all primates was male dominant and a 50% chance that the last common ancestor of all primates was female dominant. And male dominance as um as a consistent sort of behavioral system doesn't really come about until the last common ancestor of monkeys and apes. And actually we found that that male dominance is not necessarily typical of primates in general. So this hypothesis is wrong. The male dominant, female dominance does not evolve did not evolve because females selected for wimpy males who just willingly give up their the resources to the females. So a second hypothesis, you can kind of get from what I've been talking about and that's that maybe body size influences dominance. Maybe females dominate males whenever females are larger than males because females have superior fighting ability. So in some species of primates, like these Gibbons here, males and females are the same size and other species like these potties, monkeys and the mantles, males are much larger than females and another species like the injury here, females are larger than males. So according to this hypothesis, we would predict that in these species where the males are larger, males are dominant and this species where the female is larger, the females dominant and when males and females are the same size, we expect to see something called co dominance, where males and females are social equals. So what we did is we decided to test this hypothesis and we plotted the ratio of male and female body size on the, on this axis here for each species of primates according to whether they're female dominant, co dominant, or male dominant. And this dotted line here indicates where males and females are the same size, anything above the line, males are larger than females. Anything below the line. Females are larger than males. And you can see that especially when we look over here at male dominance, there does seem to be a relationship between body size and dominance. Male dominant species are generally, males are much larger than females when you see male dominance, but the opposite is not true. So here you have your female dominant species and you can have some species and males are slightly larger than the females and females still dominate them. And if you look over here at co dominance, there are some species where males are 30% larger than the females and yet males and females are social equals, or sometimes females are larger than the males and yet their social equals. And so this hypothesis doesn't work either. The data just don't support this hypothesis. So a third hypothesis is based upon some of the work that I've done about power in general, that incorporates ideas about economic theory or economic ideas into our understanding of power in animal societies. And this hypothesis says that maybe female dominance evolves when females have leverage over males. And the idea is because think about it in mammals, females control reproduction, conception, Gestation and lactation all occur within the context of female physiology. And so this may be a source of power for females. So males cannot reproduce without access to this mating opportunity. And so they need to be able to reproduce to increase their fitness. And so the supply and demand of males and females can influence power. So in some situations where you have a lot of females and a few males, then the supply of mating opportunities is high and females aren't going to have a lot of power in this situation. But in other cases where there are not many, when there's only one or two females who are ready to mate or maybe there's a lot of males around, then females are going, the supply is low and the demand is high and females are expected to have more power. So there are many ways to test this idea about economic power and lemurs. And I'm going to talk, I'm gonna talk to you about one particular test to see if female power and economic power and it takes advantage of the fact that there's a period of adolescence in chiffon. The teenage stage is when the females are about three or 4 years of age and at this time they can be sexually active, but they don't generally give birth or if they do, those infants generally don't survive. And it's not until the females are about five years of age when they become reproductively mature and we consider them adults because they reliably produce offspring at this time. So we can take advantage of this with the fact and we can test the prediction that if female power, in fact, is leverage, then female age is expected to determine the pattern of submission and only females who reliably produce offspring reliably produce offspring. Only These females are going to receive submission from the males. And so this figure shows you those teenage females and those adult females, This is mail submission to females. And you can see that the males are not very submissive to these teenage females. And it's only once females are able to reliably produce offspring that you see males starting to be submissive towards them. We can look at the reverse, We can look at female submission to males and you can see these teenage females are more submissive towards the males than the than the adult females. And we can actually then even look at the same female as she changes from one stage to another and see what that looks like. So here we have three females, Hester kita and rose. And this is female submission to males. Again, the blue is the teenage females. And you can see that the teenage females are much more submissive towards the males. But once mating is likely to result in an offspring, then you see here where the in the red circles, then the social dynamics between males and females fundamentally changes. So, um, my data, my behavioral data don't really support the male difference or the body size hypothesis. They're consistent with more consistent with the hypothesis that females have leverage. So, but I would be remiss if I didn't talk to you just a little bit about conservation. Nearly all lemurs are endangered and only about 10% of the forest is left in Madagascar. The situation is really dire habitat is being lost due to forest fires. It's being lost due to logging and charcoal production. And one of the things to keep in mind though is that the situation is pretty dire for the people as well. Madagascar is one of the poorest countries in the world. And I work in one of the poorest areas of Madagascar. And so where I work that people live in these kinds of houses and they don't have electricity or running water. So this charcoal production while it is terrible for the Lemurs, it's really important because that's how they cook their food and that's how they boil their water so that it's safe to drink. And then they need the wood in the forest to be able to build these houses to build their ox carts, they need the wood to be able to build boats. This area. A lot of the people make their livelihood based upon just fishing. What they do is they fish and they bring their food home for their family that evening and this is actually a tree that was illegally logged from the forest. And I found it in that fishing village just a few days later and these trees to be able to make these boats which are so important for their livelihood, they have to cut down for these dugout canoes, they have to cut down trees that are like this, they're really big and you know how important these really big trees are because the lemurs have to sleep in these big trees to make sure they don't get eaten by the fuchsia. So conservation is a really difficult situation in a place like Madagascar because the livelihood is very difficult for the animals as well as the people and we need to make sure that everybody can continue to survive well but a bright spot and conservation is actually the inquisitive aka research station. We've had a huge impact on conservation partly because we have a permanent presence in the force. People are in the force day in and day out. And so not only are we able to monitor activities in the forest, but people don't bother doing the illegal activity in that area because they know we're going to be there. And the other thing is we get researchers from all over the world, they're Malagasy researchers, researchers from here at UT on the U. S. But from all over the world and this brings a lot of money into the area and I'm actually one of the largest employers in this area. And because of that the people have really value the forest intact as an intact ecosystem because they know that this is what brings money into the area. And so research is actually finding that one of the most effective ways to protect and conserve habitat is actually to have a long term research station there. So if you're interested in conservation, basic science, field biology is actually a really important component of that. But let me summarize what I want you to get out of this talk. But I hope you got first. I hope you got lemurs are cool and it's really important that we can serve them. Second science is a whole lot of fun. I think I feel so lucky that I get to do this every day research as a team Support is a team sport, I could not do what I do without a whole group of people working with me in this endeavor. When you're thinking about evolution, babies are important because that is how fitness, that's how genes get passed on. And finally power is more than fighting. While fighting ability is really important for understanding power. There are other sources of power. Knowledge as a source of power and tolerance can be a source of power as well. Thank you very much. And as we say in Madagascar mistletoe Jessica. And if you want to find more about my research um or here is the website. Thank you. 

[0:47:58 Speaker 1] Thank 

[0:48:10 Speaker 0] you. 

[0:48:11 Speaker 1] Thank you Rebecca. So once again welcome to Hot Science. Cool talks are talk tonight featured anthropology professor Rebecca Lewis talking about friendship and female power and the Lemurs of Madagascar. And so now we're gonna chat with dr Lewis and answer questions from the audience and if you advance it one we'll put the slider website up and how to uh how to send in your questions. So pull out your phones and get on this app and will now have questions for dr Lewis. So I'll take the first question Rebecca. So as a Lemur lay person myself, I consider myself a Lemur lay person. I have to say Lemurs are really cool and probably amongst the most fascinating creatures on the planet. But for you, after 23 years of working with them, does it still maintain its fascination, Does it get old? 

[0:48:59 Speaker 0] You know, that's a great question because sometimes someone will come visit me and they're like, what? These guys don't do anything, they just sit there, they're really boring, they're just eating leaves all day. How can you watch them all day and not get bored? But they're always doing something that makes me laugh and they're always get these results that I'm not expecting is one thing. So I'm always having to figure out why in the world are they doing this unexpected thing? But they do really goofy things like they there's one time where there was a kid who was holding onto a little sapling and an adult male jumped on it and the tree been all the way down to the ground and you can guess what's going to happen next, right, That male jumped away and the kid was holding on for dear life, trying not to be flung off. So they're always doing these really exciting funny things that just make me laugh. And then as I said there, I keep saying, they just don't fit our expectations because a lot of our hypotheses have been developed based upon monkeys and apes. And so as I said earlier, lemurs are a great independent radiation and independent group of primates to be able to test hypotheses and when they don't fit our expectations, then, that's really interesting. 

[0:50:14 Speaker 1] Thank you questions from the audience is do lemurs who are habituated act differently from those who are not? How do you think about or study that difference? 

[0:50:23 Speaker 0] That's a great question. It would be really hard to study how different they are because you can't watch them without being there. I guess you could put some sort of a lemur cam on them or something like that and try to see. But one of the things that we do is we look and see you collect data and you look and see when you're collecting data on them when they're So there might be like when you follow them, they might be moving around a lot. And eventually they look for a period where the graph kind of levels off and where their behavior starts to stabilize. And that's when you know that they're used to you and you hope that that's as close to normal as possible. We in science strive for objectivity, but objectivity is rarely truly achievable. So you try not to influence your subjects, but there are times when you do and there was one time I remember I was a graduate student and I was out there, I was watching and all of a sudden the whole group jumped on this one male and they were pinning him down and they were attacking him and I heard this really loud noise and I was like, what is this noise? And then I realized it was me. I was screaming and I was supposed to be objective. But I was so disturbing. I realized that I was reacting to what I saw. But the lemurs, they didn't even, they were too busy with their own thing and now I'm better at controlling my emotions with it. But what happened then was the lemur who was being attacked, used me as an observer and he got away and he jumped. He could have jumped in any direction, but he jumped right over my head. So close to my hair was like floating in the wind went right over my head, presumably, I can only guess, but presumably trying to use me as a deterrent so that the other lemurs, he could have a little bit extra time to get away, but that didn't stop. The other lemurs they went past and then they're hopping down the trail and I'm running after them trying to keep up with them. But they do, you try not to influence them, but surely your presence does affect it. One major way that it does affect it is if the predators are not habituated, then you reduce the risk of predation and so luckily or not, I don't know how you want to think about it. The predators at my site. The fuchsia are very habituated to me and they hunt all around me. So I'm not deterring that. But in some places you have to be very careful 

[0:52:50 Speaker 1] neat. This question starts out with that hopping. What are their joints and spines like, 

[0:52:58 Speaker 0] oh we have an expert in the audience here, Eliza Shapiro 

[0:53:04 Speaker 1] that hopping. What are, what are their joints and spines like to deal with all that hopping? 

[0:53:14 Speaker 0] I they have spines like apes. That's how they deal with it. Yes, because they're, when they're upright, like apes are upright as opposed to the quadra pedal on their hands and knees. Hands and 

[0:53:28 Speaker 1] feet. That's 

[0:53:30 Speaker 0] the best I can do. I'm sorry. 

[0:53:31 Speaker 1] Good, Good. Next question is, have you ever missed catching a Sifaka in the bed sheet? 

[0:53:36 Speaker 0] Oh, that's a great question. It's really hard because the sedative doesn't act immediately. So the dart goes in and then there's about 60 seconds before the medication actually goes into effect. And luckily most of the time they just go, whoa, what just happened And they don't move because they're scared of, they just move a little bit, but sometimes they move really fast Into an area of the forest that's difficult to get them. And we and my team is really great. They're really experienced and they've been capturing them for years and enough as I said, is really experienced as a daughter. And so I would say 99% of the time we are able to get under there, but there is once in a blue moon, you can't it's always a risk to um, to capture animals and this is why when I do it, I try to collect as much data as possible and I try to do things like program the radio collars so that the battery lasts for years. So I don't have to capture them very much very often to try to reduce the risk to animals. But we work really hard to make sure that they are safe and and we almost always capture them, catch them when they fall. 

[0:54:49 Speaker 1] Okay. Now there are several questions along this theme. So let me read a couple of them. Are there programs for teachers to go to Madagascar and help with lima researchers? You need a field assistant. Can I go with you? 

[0:55:02 Speaker 0] I would love to say yes to everybody know it would be great. Actually, I've been working with the park service in the area and the park is opening up right next to the field station is opening up for eco tourism and we've been working with the park and with local guides trying to train them to, to understand a lot of the information build upon what we've learned from research. Um, I, uh, when I can, I do look for assistance and I do take volunteers. Sometimes. I haven't taken so many until recently because I haven't had a well and the water comes by ox cart every two or three days and it's a little bit risky to have volunteers come when there isn't a permanent water source. But I'm happy to actually announce that ut is contributing. And actually buying me a well this year. And so I am hoping to actually start a field school at the site because now that water will be reliable, hoping to start a field school for undergraduates to come to the site. And if you're interested in being assistant, you can go ahead and contact me. Well, see it's not cheap to go to Madagascar. It is halfway around the world. So that's that's something that people run into. 

[0:56:17 Speaker 1] Okay, so they asked this question, do you help the sick lemurs that you find? 

[0:56:22 Speaker 0] Oh, that's a great question. Because what do you do? So I have them down and I'm counting the ticks and lice. Do I remove the ticks and lice? Because they're doing me a favor. I've captured them and the least I could do is help them out. But then if I remove the ticks and lice, then I affect their behavior because maybe they don't groom as much because they aren't as itchy. They don't have as many ecto parasites. And so this is always a dilemma because I want to help the lemurs out. But then I'm also influencing the data if I do that. And so it depends on what the project is when the feed the, the vet was there. You know, he often would do things to help them out with their health a little bit. We just made sure that um, we didn't follow the lemurs that were affected in that way for a while and took note of some of those changes. But it's hard because sometimes as I said the the user will hunt with me standing right there and so if you see a fuse a hunting a lemur, what do you know, do you stop it? You know, it's a really, this is a, this is one of those things about ethics that we as a field grapple with and trying to figure out what is the right thing to do and for myself, I tend to try to keep things as they would be as if I were not interfering and I try, it's really hard. Like I told you I was screaming that one time I tried really hard not to interfere with the lemurs lives anymore than I already do by being present there. 

[0:57:52 Speaker 1] Okay. Next question is, did you encounter dangerous animals while in the field? And what was the protocol? 

[0:57:59 Speaker 0] You know, this is one of the wonderful things about working in Madagascar. You don't have to worry about dangerous animals. The fuchsia is about the size of a medium sized dog. So I don't really have to worry, I mean it could hurt me but I don't have to worry about my life. And um there there there are poisonous snakes in Madagascar but they all have rear facing fangs. So in order to actually get exposed to the toxins of the snakes, I'd have to shove my fist down the throat of a snake and then pull it back and so I'm not going to do that. So one of the nice things about working in Madagascar is I can sit on the ground. I can't, I can't even lay down on the ground and take a siesta if I want. I don't have to worry about about my safety because of wild animals. Where some people work in areas where there are jaguars or lions. The with the lorises, there are a number of loris is that we actually don't really know much about their social behavior. I keep asking them are they male dominated, the female dominant? What are the social relationships like? And the researchers tell me you go out there and watch them at night with lions and elephants and mambas. And we don't know some behavior about some species because it's dangerous. But in Madagascar it's nice and safe. 

[0:59:20 Speaker 1] Speaking of watching them at night, how do you do that 

[0:59:23 Speaker 0] headlamp headlamp and a good mag light. But actually I'm going to try and just got a grant and we need to be able to collect the year, the first urine of the morning and during the rainy season they actually are active a couple of hours before the sun comes up. And so I put in my grant infrared binoculars. So I'm really excited to try them out to see if this will let us watch them at night. But usually you have to, you have to use a headlamp and a mag light and do your best to keep radio collars are really important for nocturnal work because you're likely to lose them. 

[1:00:03 Speaker 1] So dr lewis some of your research centers around looking at color blindness amongst the ship and how that relates to fitness of the offspring. You didn't have a chance to talk about that today. Would you like to share a bit about that? 

[1:00:17 Speaker 0] Yeah. So, um, there is a postdoc at UT carry value and she's really interested in sensory ecology. And um, she and I were talking and Chris Kirk who is a sensory Ecologist in the anthropology department as well. A number of us were talking about, um, some of the hypotheses about why color vision, the kind of color vision that most humans have, It's called routine try chrome asi. We can see that distinguish between red and greens and why this evolved because it's not present in a number of primates. And there are various hypotheses about why you would want to be able to distinguish red from greens, why you might not want to, why you might want to be what we call color blind. And so for humans anyway. And so what we did is um, I was like, hey, you know, I actually have genetic, I have those genetic samples and so we can look and see who has a color vision try chrome ASI and who does not. And one of the things that we found because it's actually linked, it's on the X chromosome and actually color vision is a really interesting phenomenon. And that it's a case where you've got a really nice relationship between the gene and coding for a protein and that protein really what it does is it really affects the ability to absorb particular frequencies of light. And so if it's associated with the X chromosome and so males only have one X. Chromosome. And so they they can they can only see a particular frequency of a range of frequency of light. But the females have two X chromosomes. And if they have slightly different alleles on that X chromosome, then they actually can see a wider range of colors. And they're able to have distinguished red from green. And so we looked to see which which females could um or tri chromatic color vision. And then we could also do something. We could look at the this um this the fitness. We could look at reproductive success. Do females that can distinguish red from green? Do they have more babies? And do those babies survive? And the answer is no. And we look to see what about what foods do they eat? Because I collect data on the foods that they eat? We could look and see do they eat foods that are do some females the females who can distinguish red from green? Do they eat different foods. We really didn't see much difference. But actually what we found is that the males really benefit from being in a group with a female who can distinguish who who can see the three different colors. And so we were able to take advantage of this long term data set and ask a question retroactively and say, hey, can we, can we figure out why color vision evolved? And we're actually one of the first who have been able to show this kind of information with, with any sort of um mammal, I believe animal mammal. I'm looking at chris, Kirk, who who is our sensory Ecologist 

[1:03:27 Speaker 1] and chris is looking back 

[1:03:28 Speaker 0] and looking at that, he's not answering. The next 

[1:03:32 Speaker 1] question comes from laura Robinette minor. How do females interact with one another? Do they form friendships or altruistic relationships with one another or do they compete with? Do they compete with males for territory? 

[1:03:44 Speaker 0] So females and males live in a social group together and you can um and so the females stay in their natal group, most of them and males always dispersed to a different group. Once they become a teenager they'll move to and they'll start visiting other groups. Do I want to go to this group? Do I want to go to that group and eventually they'll disperse to a different group and then they'll become an adult and stay in that group for a while and then they'll disperse again they disperse every three years or so, females stay in their natal group and that means that they get to live with their female relatives, but groups are really small, so sometimes females have to leave their group as well, and so you would expect that if females are hanging out with their relatives, their daughters, their aunts, their mothers, their grandmothers, that they would have a really tight social relationships. But actually what we found this is another thing is what I love about Chicago, I didn't think I'd be spending my whole life setting them, but they just, they just don't do what we expect. You would expect the females to be good friends with each other, but they don't actually hang out together that much, they sleep together and they will sleep balls a lot. But then what tends to happen is if both females have babies, then the low ranking female tends to kind of peel off and hang out more on the periphery of the group so that she can actually have access to food because the dominant female will keep her from will prevent her from feeding in the tree with her. And and so we've been trying to figure out why in the world you have this system because you saw in that data that female rank doesn't really influence infant survival. We actually couldn't find any benefit to being dominant. And so I don't really understand what's going on, Why are the females not hanging out together. So I'm actually looking for a graduate student who wants to study this question if anybody's out there. Um So yeah they can be friendly and they can hang out together but the dominant female treats her like anybody else and we'll take the food away and hit her on the head and stuff like that. 

[1:05:50 Speaker 1] Well that's a good segue into our next question. If I want to be a primatologist, what would I major in for undergraduate school? 

[1:05:56 Speaker 0] Great questions. So primatologist, primatologist, you can study climatology in anthropology. Like I do like I am an anthropologist, you can study primatologist, dian biology and you can study primatologist and psychology, there are different approaches for each of the fields, but all of them will give you a good background. But I would say biological anthropology or biology if you're interested in field climatology, if you're interested in captive climatology, that psychology is good as well. But I would also say that one of the things you should do is take a lot of math um and computer programming. I didn't realize when I first started out it was the statistics were very different and a lot of what we do now involves a lot of computer programming and sophisticated math. So regardless of what you major in, you want to make sure you have good math and good programming or coding skills. 

[1:06:58 Speaker 1] This question comes from julie? She asked how do you pick the lemurs names? 

[1:07:03 Speaker 0] How do I pick the names? Well we take turns because I like to choose some names. And the Malagasy who work when they think they're terrible names. So I'm like, hey, this, she fox White. And so I'll name it rice because rice is white. And so the word in Malagasy for raices Vardi and I'll be like, hey, let's call this one body. And they're like, you want to call it rice were like, hey, salt is white. And so let's name it Sierra. And they're like, you want to call it salt. And so we take turns who gets to name the lemurs? Sometimes I get to name. Sometimes we just rotate through the different people who work at the site. Um, and that's so that way, nobody gets too upset about these. But one of the things that you don't want to name a lemur after somebody who you're really close to, like, I don't have a cat named Becca and I don't have a, there's not a ship named David, which is my son's name because you want to make sure that you don't form and you don't have attachment to the, the animal in a way and attribute characteristics to an animal that isn't there, It's just based upon your own experiences. So you want to try to choose names that that have, did you have a little connection to and different people do it differently. So I knew where the females female savannah. she has all of her kids have names that start with s um the site where I did my or you know, um Rose, all her kids started with our, with the site where I did my dissertation work. Each group was a country and all of the Lemurs were named for a city in the country. But the guy who was there one time, who ran that site one time, he, I guess he didn't have an atlas with him and he couldn't think of a Japanese city. And so he named a Lemur sushi and sure sure enough two weeks later, so she got eaten. And so I didn't go with that system. I went with using regular names, but in other sites, that site where I told you about the case where that Lemur was being attacked by the group members and he jumped past me at that site. They actually give lemurs numbers, they don't give them names. But to me that was mailed to 94 and that just to me, seems like a prisoner's name. So I do, I do names and we just choose it whatever people want. 

[1:09:26 Speaker 1] Okay, great, so this will be the last question I have to say. There is just countless questions here. We can't get to them all. But after this last question and dr lewis and will raffle off some of the prizes. I'm sure dr lewis will be happy to stick around and answer some more of your questions. But this last question comes from Caroline and it's one of the most well liked of all the questions asked when you were in elementary school, what did you think you wanted to be? 

[1:09:52 Speaker 0] Oh, you know, I am unusual in this situation. I've known, I wanted to be a primatologist since I was eight years old. I um I watched a lot of national geographics and this was the 1970s and so on. National Geographic had Jane, Goodall, Diane Fossey Brutus because a lot of women primatologists on TV and I thought this is what I want to do. I thought I wanted to study apes because they looked so much like us. I thought I really see humans in these primates. And so I wanted to be a primatologist and I thought I'd study orangutans and I got my red born free. And I thought, well maybe I switched for a little while and I thought maybe I would study the big cats. But when I got sidetracked for a little bit, I thought maybe I'll go into politics or law and in high school because I thought, you know what, I could probably do this better than what the politicians are doing. So I thought I'll go into politics. But ultimately, what I ended up deciding to do is to study the politics of nonhuman primates instead. But I had a lot of support from my family to be able to. They encouraged me to to follow my interests in animal behavior and climatology from a very young age. 

[1:11:07 Speaker 1] Well, please join me in thanking dr Rebecca Lewis. Thank you