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0:11
Great. Thank you so much to the organizers for inviting me. It's great to be back in Bielefeld. I've got a lot of friends here and collaborators. So it's a real privilege to be here. This is my career. In one slide, if you like. I started my, PhD working on this animal in the top left banded mongoose, and I'm still working on banded mongooses. Now, I often get asked. Surely you've found everything out. You want to know about banded mongooses, but,
0:40
I'll hope to convince you that there's still plenty to work on. And then move to a postdoc working on paper wasps. Really? An animal? Harder to get people, interested in. Unless they're scientists. Like my mum, for example. Wasn't keen on paper wasps. But, yeah, just a phenomenal animal to try and understand conflict and cooperation in animal societies. I then got interested in life history, evolution, particularly in humans and,
1:06
the evolution of the menopause, the female menopause in humans, in particular. And that led me on to working on,
1:13
killer whales, as part of a project where we tried to test some of these theoretical models to explain, the evolution of menopause in one of the only other systems where you can actually get the data to test these ideas.
1:28
And I think when I started working on these cooperative breeders, they're all cooperative breeders. I was really kind of interested in this long standing puzzle about the evolution of cooperation. But at the time I started my PhD, this book on the right came out in 1995. I may not Smith and Seth. Mary. And I also read this fantastic book by Leo books, The Evolution of Individuality and This Kind of Place. The whole problem, the behavioral ecological problem
1:59
of the evolution of cooperation in a much sort of grander setting. And I found quite inspiring to think that the evolution of cooperation, might be this repeating motif in the evolution of biological complexity. That was the kind of thesis put forward in this kind of major transitions framework. And the idea is that life has become more complex through a series of these cooperative transitions where independently reproducing units have come together
2:32
to form cooperative teams and started to reproduce as teams.
2:37
And and these formed the basis of the next level kind of forms a social ratchet, if you like, in complexity that can form the basis of the next level of complexity. So here's a little cartoon of how that process is thought to occur. So, the formation of,
2:57
selfish units, you form these kind of social groups. And through this process of conflict suppression and elaboration and specialization and division of labor, you get the formation of new units. It's also something else that happens during those, evolutionary transitions, which is that we have to change the way that we think about fitness instead of thinking about fitness at the level of these units that are making up these kind of intermediate social groups
3:23
in the middle that we have to think about fitness shifting to the success of collectives at producing new collectives. So this is a shift from what I'm calling type one to type two fitness.
3:40
These are some of the major transitions that you'll be familiar with. The origin of life is thought to have involved this kind of cooperative transition, the evolution of complex cells eukaryotes through SIM biogenesis. And this starting about 100 million years ago, the first transitions from individual organisms, what we'd recognize as the individual organism to these kind of eusocial societies, where it makes more sense, really, to think about the colony as the,
4:12
as the as the level of organism party.
4:17
And the same kind of principles have been applied to try and understand the evolution of human societies.
4:25
Though it's probably less clear how some of these ideas, particularly type one, type two fitness, whether they really map on well to understanding the evolution of, the kind of elaboration, an increase in scale in human cooperation. And also after Athena's talk, you know, it's interesting to think how you might apply major transitions theory to,
4:47
the evolution of I. So I think I've been interested in this transition because cooperative breeders occupy this muddy middle ground. They're not kind of fully integrated societies. Each individual retains the ability to reproduce itself. So they're a fantastic kind of crucible to think about the kind of forces of conflict and cooperation that are, boiling away there and helping to shape these societies.
5:15
I think I started out from much of my career interested in the evolution of help and division of labor, how conflict is suppressed.
5:23
I'm more late, more latterly. I've become interested in this transition from one type of fitness to another, because some of these cooperative breeders exhibit both at the same time.
5:34
But what I want to the other there's other processes that occur as well during these transitions, which I want to focus on in this talk. And that's the evolution of a new group identity. There's a new identity that has to emerge as a process of these transitions to higher levels of social organization. And also those social those societies make decisions. They, evolve a level of collective agency or group agency.
6:02
So I'm going to focus a little bit on, how group identity evolves in biological systems.
6:11
And also at the end, maybe make some speculations about how that relates to group agency. So that's the plan for my talk. I, I'll go through these full stages and you'll see a lot of this animal, which is my kind of go to study system to try and address some of these questions.
6:33
But first, a little quick tour of what I mean by social identity. So I'm using social identity here to mean the kind of perceived membership of a social unit, which influences how an individual acts and how it's treated by others. And I think there are three kind of main categories in biological systems which seem most relevant. There's a kind of kin identity discrimination, of which individuals are kin and which are not.
6:58
There's in some systems discrimination of individual identity with who you are matters in social interaction and as in other systems,
7:08
discrimination of group identity, discrimination of which group you belong to. Particularly in the context of intergroup conflict and being able to discriminate between insiders and outsiders.
7:22
There's a couple of points there. I think, social identity is an evolved feature of certain systems. It's not a prerequisite of social interaction. And no identity is required in many systems. And secondly, I've kind of made kin identity bigger than in this Venn diagram, because that's kind of ancestral. I think my microbes have kin identity. I'm not sure that they have individual identity. It seems kind of, to apply to a very wide range of species.
7:55
But as I say, you know, many systems don't require any kind of identity. I used to study these kind of corundum images when I was a, like my first paper was on coronal images,
8:07
which are swarming swarms of males, waiting to intercept females coming into swarms that you see quite often in, over African lakes, Great Lakes like Lake Victoria here, or mussel beds or broadcast spawners. These types of scramble competition involving one of competitions. There's no requirement for any kind of identity. You know, as far as I'm aware, no discrimination of any kind of identity. Kin identity is much more widespread and occurs in a, you know, a vast number of organisms, where,
8:42
and this is the kind of one of the two major processes that can lead to the evolution of traits by kin selection, proposed by Hamilton. If you can discriminate those that share genes identical by descent, then you can create the conditions for altruism to spread in populations.
9:07
In other systems, some cooperative, some not. You also have the evolution of individual identities famously in the face facial patterns of these paper wasps
9:20
which which, one of the few insects that exhibit, individual recognition, but also in other situations where you need to keep track of individuals, such as in dominance contests, dominance hierarchies.
9:35
In these vampire bats, where there's tracking of individual donations in in food resources or in these kind of mutualistic systems where there appears to be evidence in cleaner fish for, some level of individual recognition. And then the final level is this group identity, where you, I think, applies most to where you've got genetically heterogeneous groups, but nevertheless shared interests. So I've kind of place to sort of barrier around a collection of individuals there.
10:08
Such as occurs in, extended families and where there's intergroup alliances and so on. And these can be discriminated on the basis of, on the basis of shared phenotypic traits, which I'm going to go on to talk about a little bit more.
10:23
And I think immune systems as well, can be understood, understood as one type of group identity recognition system. I'm going to talk about two routes to group identity that are not exclusive and they complement each other. The first is to suppress individual identity or markers of kinship,
10:43
which is sometimes being called the veil of ignorance in biology,
10:47
in reference to similar ideas in philosophy and economics. And the second is to actively form a new group identity, by which you can discriminate inside. It's from outsiders in your social group.
11:06
So the veil of ignorance is a term that, as many of you will know, comes is borrowed from, John Rawls very influential book in the 1970s called The Theory of Justice.
11:17
Which itself was a kind of, had, built on an earlier ideas in,
11:27
game theoretical models of incomplete information pioneered by John Hasani, which asked what rules of resource allocation, what division of resources would a rational decision maker choose if they were ignorant of the personal gains that would result from, this allocating roles? Use that as a kind of principle by which societies might rationally choose arrangements which were just.
11:55
In biology, that term has been borrowed to, describe situations where uncertainty or in ignorance of genetic relatedness or the payoffs of social interaction can actually promote cooperation within social groups. And this is a view that's been, advocated by or an idea that's been written about, by Samia Okasha and John Strassmann and Dave Queller.
12:23
So here's some examples of of systems to which this veil of ignorance concept has been applied at the cellular level, or the intra genomic level.
12:35
The veil of ignorance has been used to describe, how
12:41
uncertainty about identity during the process of meiosis can actually prevent and suppress intra genomic conflict. So meiosis is famously usually a fair raffle where chromosomal number is halved and each chromosomal homolog has an equal chance of getting into the gamete. And that uncertainty about, kind of fixed transmissibility, transmission rate of both of these alleles or both genes on a homologous pair of chromosomes, means that the best thing a gene can do to increase its representation
13:16
in the next generation is to increase the fitness of the organism. Both chromosomes chromosomal pairs. There's also processes early in development, like the at the stripping of parent of origin markers from chromosomes that occurs during, germ cell formation in the developing embryo, which prevents there being any markers of genetic lineage within the genome. Which could otherwise break out into kind of nepotism, nepotistic conflict within the genome
13:49
in honeybee lines, queens mate with multiple males, but workers don't discriminate between the between half sisters and full sisters. They do discriminate between worker late and queen laid eggs, but cues to identity and relatedness among the offspring of queens are suppressed. And the same is true in multiple queen ants, where larvae and moved around and mixed up between piles, essentially drawing a veil of ignorance over relatedness within these,
14:20
within within these piles of brood. I'm going to give you another example of this, which is from my own research on, banded mongooses, where, this species, one of the first things I found out about it is that they exhibit quite a remarkable degree of this synchrony, which seems to mix up cues to identity in commonalities.
14:43
This is our, study site. This beautiful peninsula in the middle of lake juts out into Lake Edward in western Uganda. It's on the border with, the Democratic Republic of Congo.
14:58
And I set up this project for my PhD research in 1995 with this chap here who's Francis Mongoose.
15:08
And Francis is still the field manager of the project. So we've been together for 30 years. This is his beautiful family on the right.
15:15
And I've had the privilege of, getting to know an amazing team of Ugandan researchers who are just incredible. Anyone who works on that project knows just how fundamental, that team is to the success of everything that we've managed to do in and in the Banded Mongoose project.
15:36
It starts from kind of small beginnings. It's become quite a big project with lots of,
15:43
fantastic collaborators who I really enjoy working with, including collaborators here at Bielefeld.
15:52
So what the band of banded mongooses do. This is the first thing in the morning. They wake up about 7:00. Nice, respectable time to get up, and then they head off on a foraging trip where they dig up beetles and millipedes and things. And then it gets to about 11:00, 1130, and it gets too hot, and they just sort of go under a bush and lie around for four hours. And then about 4:00 in the afternoon, they emerge and do another foraging trip and kind of wind
16:17
their way back to the den that they're going to sleep in that night.
16:21
We have 3 or 4 groups, usually at one time, who are extremely habituated, so that out of 10 or 12 groups that we're monitoring, there's usually three or 4 or 5 that will let us get this close where we can really collect some detailed information. We track the whole population, we visit them on a daily basis, and they kind of weigh themselves, which is handy.
16:45
And we've got a very large database which over the years, and we've added really kind of some fantastic cutting edge techniques to try and understand, individual relationships and physiological effects and genetic related relationships within this population. So Hazel Nicholls has led the genetic work and working with Jo Hoffman here at Bielefeld, Faye Thompson has been really very important, putting the life history data together. I do want to kind of
17:15
put a shout out to my current postdoc, Laura LaBarge, who's got this amazing task of trying to set up a reverse GPS tracking system and dealing with just amazing, logistical challenges right now in the field in Uganda and solving them. We've also started using drones and automated tracking, which is part of our kind of current, you know, sea Grant to try and use these techniques to understand, leadership, cohesion and dynamics, within, within groups.
17:51
But I'm going to talk about bird synchrony. This is, like I say, this was the first thing that I discovered in doing my PhD. And, you know, you'd follow a group and there'd be 4 or 5 females who are heavily pregnant, one day, and then you'd go about the next day, the males come out of the den at the normal time, but the females stay behind. And then about 1030 the females emerge and they were all slim. We realized that they'd given birth together on the same night, same morning, as it turns out.
18:22
And this wasn't just a one off. This is kind of the norm. So on average, around about 4 or 5 females give birth synchronously on each breeding attempt. We've had up to 12 once. 12 females synchronized birth to the same day.
18:38
And they the mothers suckle those offspring without any discrimination at all of kinship. So those kind of we're looking around and pups will move from one female to another. So there's no discrimination of maternity within these litters.
18:54
And after the pups emerge, they do another weird thing, which is that they form 1 to 1 relationships with particular adult helpers that we call escorts. And those escort pup pairs are also no more closely related than you'd expect by chance. There's no apparent discrimination of kinship in the formation of these these kind of teacher student relationships. And those escorts will care for the offspring. They teach them foraging tricks,
19:20
and so on. We know that asynchrony is really bad. About 30% of litters are asynchronous naturally. And in that in those litters, many fewer pups survive. And they tend to die very quickly. Particularly the females who give birth early, their pups usually die straight away. And lots of anecdotal evidence suggests that those pups are killed by other females that are still pregnant.
19:54
This kind of effect of birth order on infanticide is actually quite a general pattern that you see in lots of cooperative breeders.
20:03
Where females seem to be infanticide or until they produce their own offspring.
20:10
But I did an experiment starting in 2007. I got a three year grant, and it took seven years to do the experiment.
20:17
To try and manipulate the the distribution of reproduction among these females to try and understand the costs and benefits of sharing reproduction, and also the kind of behavioral mechanisms that were used to enforce control over reproduction. So for some of these, breeding attempts, we suppressed this is a before the use of short acting contraceptive injections.
20:43
This is before this is where we suppressed all the subsequent breeding attempts. So these are dominant females and that was that. So, so females and then that's after. So you can see we were successful at of switching off the subordinate females group for one breeding attempt here. I kind of turned them into meerkats. So I was trying to kind of produce, take the oldest female and just leave her as a breeder. And here we suppressed all the subordinates.
21:10
This one, I really thought that they would do much better, because I thought, you're removing competition from these other females, that the survival of those offspring will be better, that they'll have this more efficient division of labor, as you find in the cats. But it didn't turn out like that.
21:27
We've got these very strong patterns of litter death in the first week where there was no real, effect when we switched off. So female subordinates, but if we switched off any of those dominant females and the litter was died very quickly. In fact, I kind of stopped this experiment after eight breeding attempts because it was clear that there was a very strong pattern there.
21:52
An unexpected pattern. So for ethical reasons, we kind of curtailed the experiment.
21:59
So I think this is a this was quite difficult to get experimental evidence that
22:06
dominant females do kill litters which don't contain their own young, either because they're still pregnant or because they haven't contributed to a communal litter.
22:15
And that fits with the idea that birth synchrony, if you can synchronize birth to the same day as dominant females, then there's this mixing of cues to maternity, which leads to no infanticide. And allows subordinates in particular to have surviving offspring.
22:39
Who oops. What are the consequences of this fail of ignorance? And I was kind of interested in this prediction of roles, that from Behind the Veil in the this was a verbal model of roles from behind this veil of ignorance. What rational actors should do is allocate resources in a way that provides maximum benefit for the least well-off, which she called the maxim in principle,
23:03
and that would typically reduce inequality.
23:07
So we did an experiment where we fed half the females in each group during pregnancy, which increased inequality. Those females we left the other half of pregnant females as controls within the group. They all gave birth on the same day. And then we followed what the patterns of care were. This was an experiment led by Harry Marshall and Robert Passenger, who was, developed an amazing way to feed females selectively. Some very difficult thing to do. So we were successful
23:38
at creating inequalities so that if we fed females in the latter half of the pregnancy, they produced bigger pups.
23:47
But then typical mongoose style, they did something really weird, which was that those fed mothers who were happier and in better condition went and spent most of their time escorting the smallest pups in the litter. Who were the the control pups, the pups of the nonfat females. And that resulted in a leveling up of, pup weights. So this is inequality on the right before this is before the period of postnatal care. As a consequence of this strange pattern of postnatal care,
24:20
they were successful in reducing inequality in these litters. Whereas the letters that we didn't manipulate, there was no change in the level of inequality.
24:31
So birth synchrony in banded mongooses does seem to remove cues to kinship. It prevents infanticide, and it promotes fairness in the distribution of resources in a way that's kind of consistent with this maxim in principle, that care is allocated to provide the greatest benefit to the most needy.
24:49
So this is what ChatGPT makes of, it's kind of Marxist mongooses.
24:58
And we showed theoretically that this maxim in principle can actually which has been debated quite a lot in economic game theory. And Hasani wasn't very keen on the maxim in principle can be adopted when the stakes are very high. And the best thing is to avoid being in that worst off position.
25:14
Okay, I'm going to quickly, just this is much quicker talk about group identity because this is work in progress. I want to talk about this kind of second process, not the stripping away of individual identity, but the formation of group identity
25:29
and the idea that I think it's particularly relevant and particularly conspicuous when in the context of extreme intergroup conflict, which is another feature of the mongoose system. So these labels of group identity can take many forms, I think in immune systems, in some microbes they take the form of surface proteins and many social insects,
25:52
these are used as markers of group identity or other volatiles in mammals and in humans. Dialect, symbolic markers, languages, and so on.
26:03
So existing theory says that, you know, good group identity labels should be traits that are shared by members of the same group and not shared by members of different groups that make sense. They can be genetically determined. A lot of the insect, theoretical models, social insects assume that the genetically determined or they can be learned or environmentally acquired, but all for the generally thought to be kind of self-controlled.
26:30
And the idea is that, you know, if you've got like this actor on the right who's like a, guarding the entrance of a nest or something, it's got to tell whether to let this ant in. The ant, the recipient kind of comes up with a label. The actor compares it with a template that it's got a kind of cognitive representation of a template, perhaps, and decides on its optimal response.
26:54
And the difference between the template and the label can be used to make a, make a discriminating decision. So you can set your discrimination threshold somewhere along this axis of the difference between the actors template and recipients label. If if you kind of increase your threshold and allow more difference, then you run a greater risk of letting in, individuals that don't match your group. If you set it too stringently, then you run the risk of excluding those members of your own group.
27:32
In error. So that's fine. But in many in current theory, these distributions of group identity are fixed was whereas in many animals, I think they're the result of behavior. I want to kind of illustrate that by showing you some videos of mongooses quickly. This is mongoose is kind of lining up against each other in what we call battle lines. And you'll see that this group at the bottom here, I want you to watch for sort of rubbing against each other, which we call Alo marking.
28:26
And what's happening about one of them are dragging the anal pouch over the phone.
28:34
It's chaos. By the way. And in the heat of battle, I think that these kind of the smell of animals is used as a really quick check of who they are, rather than visual cues. I mean, visual cues and so on, I'm sure contribute to identity in mongooses, too. But in the heat of battle, smell matters is the one who you understood as a loving you. Show you the full speed, and then I'll walk you through a slow motion version of weaponizing that to fight against
29:06
an animal here or there. It's going to get caught.
29:17
In. But to rescue?
29:21
Yes or no?
29:26
Apologies for the samba. Is this. I'm going to give you a selection replay of that. These are two main protagonists here. This guy is going to come and be the rescuer. This one is the one that's going to be overconfident and make a miscalculation and end up caught. So at first he chases off
29:46
at the bottom. I'm stuck around and now he's overconfident, leads the charge, and he's going to come face to face. These will flee. He's going to come face to face with a mongoose that doesn't flinch.
30:00
Which is quite interesting. So it's going forward. And it's the guy who's not flinch. He thinks, Ryan, have you. And here's his henchmen. He's a male who's the henchman coming. And now he's caught in trouble.
30:17
0000.
30:25
And mongooses can get really, seriously injured. Killed in these kind of fights.
30:33
Is not the protagonist. He's coming back and he's going to kind of. What we do is he was very interested in trying to get a sniff of who is who has been caught. Who?
30:56
They came back, has brought his other group mates. I think he gets into something else, but they look, they're going straight for the smell. So we expect that kind of fighting. And so anyway, I'm going to speed up a little bit. One other video the other time that they do a lot of other marking is when for some reason if you pour water next to them, they just do this crazy thing.
31:34
They don't do it when elephants urinate and a lot of our markers
31:42
interesting. So we've got a hypothesis that it's really kind of, you know, if it's if you've got if all your conflict is kind of within group, then it pays to be to advertise your individuality. But if most of your conflict is, between group and it can pay to homogenize these labels, and then I, the thing I'm interested in is that the mongooses are flipping between these states. You know, it's the squabbling amongst each other. If another group appears, then they go and start rubbing each other
32:16
and go into battle. But this kind of movement, this is not kind of fixed template distributions, this these are kind of behaviorally mediated.
32:26
And with Rufus Johnston at Cambridge, we've kind of done a model where you can behaviorally push these distributions closer together, further apart to try and homogenize your labels.
32:39
Which produces some interesting predictions that we want to test. So basically when you and the opposing group are of intermediate dissimilarity, then you should get, maximum homogenization method. And in that grant we're going to try and take that model and test it with Barbara Casper's and Hazel Nichols and Zaf Harrison. By analyzing our marking before and after these conflicts and looking for homogenization, we're also going to trace the longitudinally the kind of micro
33:12
anal pouch microbiome which we think is the source of this individual identity. Right. I'm just going to very quickly have some speculations about cognitive, the cognitive dimension of identity, you know, some interesting ideas in the psychology literature, the idea that in times of war or in extreme duress, this what's known as identity fusion, humans undergo identity fusion, which is this visceral sense of oneness with the group and the kind of merging of the self with that of the group.
33:43
And that's been used to explain these crazy acts of self-sacrificing war running towards machine gun encampments and so on. And it's distinct, really, from these kind of ideas about what makes humans unique cognitively in terms of cooperation, the idea of sharing intentions and sharing plans and so on, which has been stressed by some researchers. It's more just a summation of of the individual's identity.
34:12
I like this kind of idea, first of all, because, the mongooses, I can I can believe that the when the enemies on the appearing in front of them, they don't care about anything else other than fighting, you know,
34:28
they're not aware of you. They're no longer, you know, they're not aware of each other. They're not competing. They're just for that moment in time that that kind of fuzed. And this fits with this interesting slightly out there theory. I think from away from the mainstream in economic game theory, the idea that humans have the ability to flip into a different cognitive frame. So instead of asking themselves,
34:54
what should I do in any particular game situation, they have the capacity to flip into this mode, asking instead, what should we do? It's an alternative model of rationality. And back. Right? This book that I was very influenced by, by Michael Bacharach, suggests that this capacity has evolved by into strong intergroup competition between group selection.
35:18
But it's a sort of idea that doesn't require much complexity in terms of sharing intentions and joint commitment and so on. So I think it could apply to things like wasps and mongooses quite well, actually. So, that's something that I would like to explore in future. And the final thing I'm going to say is that in mongooses, your identity can switch pretty quickly. So this is from a paper I wrote in from my PhD where I say that, you know, there was a female group occupying an area
35:48
and they were kind of fighting with their neighbors, and particularly this one big group. And we we were watching them fight. And then I went away thinking they'd gone into the bushes. It was 12:00. I thought, okay, nothing's going to happen. So I came back at 4:00 and a whole load of males had left and joined that group and were fighting against their natal group, really vicious fighting against the group that they been born into and spend their whole lives in, in up until that point.
36:15
So something had changed cognitively. They'd cognitively switched identities to these other groups.
36:21
So I hope I convinced you that there is something interesting to explore
36:26
using animal societies about these two other,
36:31
aspects of major transitions which allow this interesting phenomenon of unity with while retaining diversity. And that's it. Thank you for listening.
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