welcome to the primate cast hey everyone now Andrew we are pretty fortunate here at the Primate Research Institute because we get a lot of interesting visitors coming for a lot of different research purposes we do indeed and it's really nice for us doing this uh podcast when they come we kind of take them aside and ask them if they'd like to sit down and talk about their research yeah and fortunately people are usually pretty willing to do so so we have a bit of an archive now that's a that is continues to grow and today what we like to do is get back on top of that and bring up one of the interviews we conducted in March of this year 2012 with Dr sirel grutter mhm yeah and so he was visiting Japan um and specifically the Primate Research Institute to meet with some collaborators um Dr Goro and Dr yam tsuji to talk about temperate primates and the Ecology of temperate primates and also Dr IIM matsura to talk about a an upcoming special issue in the international Journal of primatology on multi-level societies MH um those two are are putting that together or have put that together with Dr champ Pang in in China as well and so we were we were happy to have him sit down with us in the podcast absolutely and we should probably just get right into that sure all right so here's the interview there he is so we're joined here with sirial grter who's visiting us well from from where are you visiting us today um actually from Switzerland yeah I completed my post-doctoral work at the max plank instit in Germany in Li and now I'm basically jobless for a few months but I will soon start a new position in Australia a teaching position and research position yeah right yeah and so in Australia you where will you be based in per at the University of Western Australia in the department of human biology and Anatomy okay yeah well congratulations on the new position thank you very much great and bringing primatology to Australia exactly many primates there but I mean it's mostly um morphological research that they are doing some uh neurobiological research physiological research endocrinological work so I would like to cover the primatological aspect yeah okay so the term primatological itself is pretty diverse so so what is your background then uh I'm mostly interested in primate social Evolution what are the costs and benefits of group living in primates and I'm particularly interested in one type of social organization in multi-level societies okay multi-level societies are probably among the most complex primate societies because you have several social levels you usually have uh one male units or harm units at the basis and then there's higher levels of social grouping like bands or communities or whatever and there's only very few primate species that exhibit such a multi-level societies like gelada baboons or Hamed rise baboons and also some cabines like rhinopias and also humans basically live in a multi-level societies we have family groupings that get together into larger social units yeah that's right and and so Japan actually has a bit of a history in primatology studying species that exhibit these multi-level societies did you have any connection to the researchers here previously uh so for example AKO Mori did some work with gelata baboons yeah I and I'm aware of his work with gelada yeah yeah and then more recently we had a a PhD student in postto Chang from from China who studied the the sichan No No monis as well exactly right so Chang pong and ikim matsuda and me we are working on a special issue on multi level societies to be published in the international Journal of primatology okay it's for the first time that we're trying to get together researchers studying different kinds of primate species also non primate mammals that live in multi-level societies and try to integrate all these findings into into co coherent model or whatever yeah it's quite a daunting test because it's such a complex phenomenon but that's right and you were describing earlier that that editor of igp was okay with you bringing in studies on well what what what else is going to be in the special issue well there's one paper on sperm whales which live in very complex societies one on Asian and African elephants and one on human Hunter gers okay W so when can we expect to see this uh I would say Pro two papers two contributions have already been published on the website but we expect the special issue to be ready sometime later this year probably by the end of the year it should be should be out yeah okay yeah that's pretty cool that you uh studied in China how did you get Affiliated there and start your studies there because they have so many primates but not a lot of research going on that's true I mean it's extremely difficult uh to establish a research program in China as a foreigner I mean first of all um you need to find a counterpart you know that helps you to get the permit to work in a national park something like that you need to learn some Chinese without any Chinese you can survive in China that's for sure how's your Chinese uh I would say my Chinese was quite good in like 2007 you know like my Chinese peaked when I was actually in the field and I had to use it every day yeah but now it's kind of it has yeah suffered a little bit yeah okay yeah but I can still get by I can communicate yeah great and have you always had a focus on the multi-level Societies or how did you get interested in that topic I actually first got interested in rhin aticus before I got interested in multi-level societies I was a bit naive when I had to decide on a topic for my masters and I was basically looking at that pictural guide of living primates and uh for the snupn monkeys there was a lot of missing information so for several social variables It Was Written na not applicable or not available or whatever so this kind of uh got me thinking you know and that I I wanted to figure out why is there nothing known about their social behavior and their social organization and then I went to China for the first time in 2001 I just wanted to explore the area I want to see uh the the natural environment where this rhin aticus live in yunan Province and I quickly understood why nobody has done any research there because it's extremely rugged terrain um it's in Winter it gets very cold it's snow covered and it's very remote and it's not an easy place to do field work that's for sure right and I didn't even see any snos monkeys during my first trip yeah wow I'm sure a few of the listeners might have had similar experiences in their own fieldwork yeah and then I decided to do my Master's research in captivity working with a captive population of ripus beti there's no ripus beti held outside of China so there's only two captive populations one in Beijing one in King so I decided to do my research on the population in King okay and it was generally about social behavior I I started with an ethogram and then I moved on to study postc conflict uh Behavior okay um I Quantified levels of aggression and I Quantified uh conciliatory Tendencies and something like that and we found that there are actually they live in a highly egalitarian system they have very high postc conflict uh consiliary Tendencies so which is typical for cabines yeah okay and so how long did you spend in the field during your phc work it was 18 months 18 months and you mentioned earlier that for 14 of those you had no idea exactly how many monkeys you were studying yeah uh local people kept telling me that there were about 200 individuals in that group but I just couldn't verify that information because most of the time we saw just a part of the group uh up in the tree crowns we had no idea of how many individuals were down on the ground or in the underst story until one day in 2006 um when the group crossed an open area it was a gap in the canopy like a golly or something like that I could actually for the first time count all the members in the study group and I was amazed when I realized that there were more than 400 individuals in the group it was 410 individuals that I counted which is quite amazing so that seems to be the thing with these multi-level societies right we're talking about a way to kind of structure an incredibly large number of individuals into some kind of a coherent system exactly right in most Asian cabines we we we find one M units single independent one M units but there's only very few taxa where these one M units get together in larger bands so the question the question was what are the benefits and what are the cost of living in these very large bands mhm and well as for the the benefits I mean first of all you need to have a large resource base that allows such large groups to form like in chelot baboons you have this Alpine grasslands where where a thousand geladas can feed simultaneously without experiencing substantial feeding competition and with the ripus it's basically the same because there's staple food or they staple fall back food is lyans and lyans are quite abundantly available almost every conifer tree in their natural habitat has some uh lyans hanging down from the branches so this is the ecological precondition for forming these large multi-level societies but that doesn't explain why this particular social system has been selected for so there must have been another reason MH and um predation doesn't really make sense because there's no need to form such super groups to be protected from predators I think 100 individuals would probably be sufficient because uh the the benefit of uh being protected from predators uh the group size benefit at some point probably saturat so there's no need to form groups of this magnitude and may actually start dropping the other side of the slope if the group then becomes more obvious yeah exactly what kind of predators do they have to deal with well they use they well these days they don't have any natural Predators maybe maybe leopards or maybe clouded leopards but we haven't found any evidence of predation and there is a birds of prey that might catch a juvenile or an infant that is playing up in the tree crowns but I don't think that predation explains why they formed these large groups so we were trying to uh look at Social um factors that might play a role like um the threat of Bachelor males yes we know that in these large m Lev groups there's also very large Bachelor groups that are always hanging out at the periphery of the Bands so they're basically constantly following the bands and they pose a constant threat to the unit leaders to the harm owners so it has been shown for uh sebras that when stallion get together the chance of being attacked or harassed by a bachelor declines okay it's basically a safety and numbers effect and with the sebras it has also been shown that these stallion males they they collap at in attacking the bachelor males okay so I was trying to test this bachelor threat hypothesis for rhin aticus and do the bachelor males if they do succeed in getting into the group commit infanticide they take over the group and infanticide has also been uh demonstrated yeah it has also been shown in the field yeah that they do commit infanticide okay but it was very difficult to test this hypothesis in the wild so I I chose another approach I did a comparative analysis I extracted information from the literature about the presence or absence of modularity by modularity I mean this tendency to get together into larger bands having extreme home range overlap and so on and we actually found that in those populations where there's a lot of Bachelors around the tendency to form uh multi-level societies is much higher there was a significant difference yeah very interesting and we Quantified the presence of Bachelor May by looking at the sex ratio of the bisexual population Yeah the more biased the sex ratio of the uh bisexual population the more males are expected to be excluded and the higher Bachelor threat is expected to be so we found this neat correlation between these two variables so there seems to be an effect of Bachelor threat on this tendency to Aggregate and the same model has been tested with gelada baboons recently and they found exactly the same okay so it might be something that's a little general and robust they call it the the the we we could also call it the social Predator hypothesis it's not natural Predators it's social predators that have an effect on grouping patterns okay so completely changing gears here so at MPI then you left China and you started work on mountain gorillas yes I started working on another Montaine primate population yeah from the mount from the Himalayas to the vironga volcanoes in central Africa yeah okay so what was that experience like then I mean there's obviously a lot of history you're working at the K Institute there I mean I felt very privileged to be able to study those mountain gorillas that D fosy habituated for uh to to human beings I mean it was it was an amazing experience and it was so different from working in China because the those gorillas are fully habituated so you could actually get very close to them you could individually recognize the animals right you you you knew all their individual life histories it was a totally different experience and there are not 400 of them in one group although the the average group size has increased over time now the average group size is much larger than in the past okay I mean the whole population has increased from 250 in the 1980s to 480 in 2010 and the average group size has gone up as well so we were basically interested in whether these gorillas in the veruna volcanoes still have sufficient resources whether they are approaching the carrying capacity I see so we had some comparative data about food availability that were collected 20 years ago and we resampled the same area we we re replicated the same study in order to find out whether food availability has changed as the population density has increased and so my understanding is that specific place kind of also has a long history with conservation so does your studies have kind of a conservation aspect to them absolutely I mean these results are obviously very important for conservation management I mean the virunga volcano it's basically a forest Island which is surrounded by agricultural Fields so there's no way of dispersing or of moving to another empty habitat for the gorillas are basically confined to this patch of forest and at some point the population will reach its carrying capacity we just don't know when this will happen and there's been lots of studies on other mammals where the population has reached a peak and then the population just crashed so something like this could also be we could predict something like this for the gorilla population so I believe it's very important to monitor the food resources because that's what sustains the population everybody's happy about every newborn gorilla and about the constantly increasing population size but not many people are actually worried about what does this mean in in terms of resource competition in terms of resource availability sustainability of the population yeah so what's next for serial grer I I if possible I would like to continue working on these two species yeah and keep working on multi-level societies and maybe expand the Horizon a little bit by also starting to think about humans about the human social system what are the parallels what can we learn about this Human Social evolution by studying multi-level sociality in non-human primates okay sounds exciting wow and is there any Crossover with kind of ethnography you mentioned small scale Societies in Africa before y so are you studying them in terms of multi-level uh not me but who knows maybe that's a possible project for the future yeah yeah obviously yeah I think it would be worthwhile to actually cross the Gap and and bring these two disciplines together cultural anthropology biological anthropology well it's funny because there's there's generally been a trend to widening the gap between those two Fields right sometimes I remember Bill McGrew when he when he gave his final round up for this uh small Symposium we had in Kyoto a few years ago his uh main point was we've seen a lot of interesting research from a lot of young scientists but one thing that he he wanted to put a call out for was to bring more anthropology back into primatology yeah yeah it's interesting uh just before I forget too what are you doing here in Japan um I'm working on a special issue together with uh Yamato and Goro so that's Yamato Tui and Goro exactly right yeah so we had a symposium at the International primatology Conference in 2010 in Kyoto about adaptations of primates to temperate environments so what what kind of strategies do they have to cope with extreme resource season seasonality with extreme cold with lack of resources in winter so that was the idea because that's exactly what the snubnose monkeys also experience they experience um a shortage of food resources in winter in Winter there's basically no fruits available no leaves available so they have to come up with some fallback strategies to to survive so we are basically comparing strategies in cabines versus strategies in Max to see whether there's differences or similarities in order to explain how they have conquered the the temp temperate zone yeah primates of the temperate zone I like it well there's also human primates in the temperate zone and there there were neander TS I don't know maybe this will also shed light on human evolution who knows all right s well thanks for joining us on theate cast thank you much yeah