Unraveling Ecological Effects on Social Behavior. Insights from Tent-roosting Bats

Although group living has been associated with high fitness cost, multiple lines of evidence have suggested that it has evolved multiple times independently. Given the wide diversity of social systems, it appears that multiple explanations are necessary to understand this process. Although evidence indicates that multiple ecological and environmental factors might promote variation in cohesion of social organisms, studies investigating how these factors interrelate and shape social structure have been limited. In the tropics, there are at least 23 bat species that roost in modified structures called tents. These species present a wide diversity in social systems. Moreover, they have divergent evolutionary origins but similar roosting habits, suggesting convergence in roost use. These characteristics make this group an ideal system to test hypotheses regarding effects of ecological and environmental factors in evolution and stability of social groups. Thus, my objectives were first to investigate the importance of habitat factors in predicting presence and density of the tent-roosting bat Uroderma bilobatum. Additionally, I wanted to determine relative contributions of habitat factors on group cohesion and stability. I found that presence of coconut palms (Cocos nucifera) had the highest unique predictive power of presence and density of U. bilobatum. Additionally, I found that roost characteristics contributed more to the explained variation in group relatedness. This pattern was driven by relatedness of adult females within social groups, suggesting that females using roosts of specific characteristics exhibit higher relatedness. To determine if this pattern holds across multiple tent-roosting bat species, I tested for correlated evolution between group stability and roost lifespan. I found that most bats that used tents of short lifespan also had stable groups, and most species that used tents of long lifespan had unstable groups, suggesting that group stability and tent lifespan did not evolve independently. The observed relationships between roosting ecology, group cohesion and stability in tent-roosting bats suggest that roosts play an important role in the evolution of group formation. Incorporating ecological and environmental factors in the study of sociality will allow broad understanding of the forces that bring together individuals into cohesive social groups

Využití metod experimentálních her ke studiu kooperace, altruismu a férovosti a jejich biologických prediktorů

Kooperativní, altruistické a férově se projevující chování představuje důležité téma evoluční a behaviorální biologie a mechanismy vedoucí k jeho evoluci, ultimátní i proximátní prekurzory, jsou předmětem mnoha výzkumů v biologii i společenských vědách, teoretických i experimentálních prací. Ve světle teorie life histories jsem se zaměřila na vztah zdravotního stavu jedince a kooperativního chování u lidí a testovala hypotézu, že zdravější jedinci budou projevovat kooperativnější tendence (a to zejména díky větším možnostem budoucích interakcí a dlouhodobých zisků) a naopak. Data získaná od vzorku univerzitních studentů hrajících experimentální hry (hra na diktátora, hra na ultimátum, rozšířená hra na ultimátum, hra na důvěru - též překládána jako investiční hra - a obrácená hra na diktátora) a vyplňujících dotazník zaměřený na zdraví a osobnost nepodpořila tuto hypotézu. Mé další hypotézy - že lepší pamět a nižší temporal discounting budou spojeny s kooperativnějším chováním (vycházející z podmínek pro reciproční kooperaci) - byly daty podpořeny, nicméně pouze částečně v případě paměti. Data z pěti experimentálních her jsem také využila ke stručnému popisu podílu různých typů chování (sobeckého, altruistického, férového a kooperativního) ve studované populaci, přičemž jsem se zaměřovala na...Cooperative, altruistic and fairness-exhibiting behavior is an important topic in evolutionary and behavioral biology and the mechanisms leading to its evolution, ultimate as well as proximate precursors, are subject of much research in biological as well as social sciences, theoretical as well as experimental work. In light of the life history theory, I focused on the connection of one's health state and cooperative behavior in humans and tested the hypothesis that more healthy individuals would manifest more cooperative tendencies (as they would have more opportunities of future interactions and long-term benefits), and conversely. The data, obtained from a sample of university students engaged in experimental games (Dictator Game, Ultimatum Game, Expanded Ultimatum Game, Trust Game, and Reversed Dictator Game) and a health and personality-focused questionnaire, did not corroborate this hypothesis. My other hypotheses - that better memory and lower temporal discounting would be related to more cooperative behavior (stemming from the conditions for reciprocal cooperation) - were supported by the data, albeit only partially in the case of memory. I also used the data from the five experimental games to briefly describe the proportions of different types of behavior (self-regarding, altruistic,...Department of Philosophy and History of ScienceKatedra filosofie a dějin přírodních vědPřírodovědecká fakultaFaculty of Scienc

Morality as natural history

What are moral values and where do they come from? David Hume argued that moral values were the product of a range of passions, inherent to human nature, that aim at the common good of society. Recent developments in game theory, evolutionary biology, animal behaviour, psychology and neuroscience suggest that Hume was right to suppose that humans have such passions. This dissertation reviews these developments, and considers their implications for moral philosophy. I first explain what Darwinian adaptations are, and how they generate behaviour. I then explain that, contrary to the Hobbesian caricature of life in the state of nature, evolutionary theory leads us to expect that organisms will be social, cooperative and even altruistic under certain circumstances. I introduce four main types of cooperation: kin altruism, coordination to mutual advantage, reciprocity and conflict resolution and provide examples of "adaptations for cooperation" from nonhuman species. I then review the evidence for equivalent adaptations for cooperation in humans. Next, I show how this Humean-Darwinian account of the moral sentiments can be used to make sense of traditional positions in meta-ethics; how it provides a rich deductive framework in which to locate and make sense of a wide variety of apparently contradictory positions in traditional normative ethics; and how it clearly demarcates the problems of applied ethics. I defend this version of ethical naturalism against the charge that it commits "the naturalistic fallacy". I conclude that evolutionary theory provides the best account yet of the origins and status of moral values, and that moral philosophy should be thought of as a branch of natural history

Genetic relatedness and socioecology of wild Hanuman langur monkeys

This genetic study is based on a geographically isolated population of Hanuman langurs that live around the city of Jodhpur, north-west Rajasthan. Here, the majority of langurs live in harem troops (with a single resident male for 95% of the troop's history) and bachelor bands. Behavioural studies of these langurs suggest that the troops are matrilineal, with males being the dispersing sex. It has therefore been hypothesised that females of a troop are closely related, both through their mothers and through cohorts sharing the same father. This would explain the high levels of cooperation seen between females, such as allogrooming and home range defence. Conversely, members of all male bands, particularly the young adults who control the bands' movements, are unlikely to be related, because of the constantly changing membership and the high mortality rate suffered by the nomadic males. This study has tested these hypotheses using non-invasive techniques to obtain DNA samples from troops and bands in the population. 89 individuals of five troops and one band have been genotyped at eight polymorphic microsatellite loci. Analysis of the microsatellite data using Queller and Goodnight's RELATEDNESS and KINSHIP programs has shown that on average, troops are related by 0.17 ± 0.04, troop females by 0.14 ± 0.07, and non-adult troop members by 0.27 ± 0.07. Conversely, the relatedness of the band was only 0.05 ± 0.08. In three troops the resident male could not be excluded as the father of any non-adult, suggesting that these residents had had long term mating monopoly in these troops, whereas in the remaining two troops where takeover had recently occurred, the new residents could be excluded as fathers in all but 2/12 cases. Additionally, the population proved to be highly structured, and troops appeared outbred, an indication of female philopatry combined with polygyny. These results provide genetic evidence in support of the social organisation suggested from long-term behavioural data

Biological Evolution and Statistical Physics

This review is an introduction to theoretical models and mathematical calculations for biological evolution, aimed at physicists. The methods in the field are naturally very similar to those used in statistical physics, although the majority of publications appeared in biology journals. The review has three parts, which can be read independently. The first part deals with evolution in fitness landscapes and includes Fisher's theorem, adaptive walks, quasispecies models, effects of finite population sizes, and neutral evolution. The second part studies models of coevolution, including evolutionary game theory, kin selection, group selection, sexual selection, speciation, and coevolution of hosts and parasites. The third part discusses models for networks of interacting species and their extinction avalanches. Throughout the review, attention is paid to giving the necessary biological information, and to pointing out the assumptions underlying the models, and their limits of validity.Comment: Review article accepted for publication in Advances in Physics. 106 page

Defining the mechanisms of a cooperative computer system based on theories of cooperation

There is a growing interest in the development of computer systems that are actively involved in the tasks of the users and serve to augment the users' creativity. Cooperative computing is a major contribution to this research field. A survey of current developments in knowledge based systems led to the conclusion that there has hitherto been an absence of a formal definition of the mechanisms of cooperative computer systems based on theories of cooperation. The work in this thesis seeks to provide a full definition of cooperation derived from the behaviours of living cooperative systems. Studies on human cooperation and cooperation in the animal kingdom, established that cooperation is a dynamic behaviour; in that the interaction processes between the cooperative partners serve to facilitate the achievement of a common goal, or a set of goals that are mutually desired by the partners. Partners in cooperation are interdependent: one member's actions are contingent on another. Therefore, the underlying processes which induce and maintain cooperation were identified. These are: communication between the partners; emergence of norms and roles governing the behaviour of the cooperating members; resolution of conflicts; distributed and coordinated activities. These factors were further elucidated within the context of small problem solving groups. A model of cooperationw hich encapsulatedth esef actors was produced. From the discussionso f the advantageso f cooperationw ithin different contexts, the potential for synergy was found to be the main benefit of cooperation. The potential for achieving this synergy between a human and a computer is the main motivation for the work undertaken in this research. From the theoretical analysis of cooperation, the underlying mechanisms of a cooperative computer were successfully defined. A conceptual model of human-computer cooperation was presented. It was established that the quality of cooperation is closely associated with the nature of the task. Therefore, it is not practicable to produce a general purpose cooperative system. A specific task must be used. Creative tasks of a problem identifying and solving nature, were found to be more suitable to cooperative behaviour than others. Typical of these, and the one selected, was computer screen design. Current screen design practice was analysed, and the functional requirements and knowledge base needs of the systems were established. The underlying mechanisms of cooperation were formalised and successfully implemented within a software exemplar, named COSY. COSY exhibits the behavioural characteristics of cooperation, and utilises the knowledge of screen design to support users in the task of formatting computer screens. COSY successfully demonstrated the synergistic relationship in its cooperation with the users. It is concluded that the approach undertaken in this thesis has lead to a successful definition and implementation of the formal mechanisms of cooperation in a computer system, one which potentially enhances the innovative and creative aspects of design work

Functional and organizational aspects of vocal repertoires in bottlenose dolphins "Tursiops truncatus"

Bottlenose dolphins (Tursiops truncatus) produce a wide variety of sounds but little is known about the function and organization of their vocal repertoires. This thesis investigates several aspects of call usage and compares the biological validity of classification methods for dolphin whistles. Passive acoustic localisation methods were used to identify which animal produced a sound. Observations of captive dolphins in the Zoo Duisburg, Germany, showed that signature whistles are almost only used when the group was split up, but not if all animals swam in together in the same pool. This finding supported the hypothesis that signature whistles are cohesion calls. Whistles from these observations were used to compare whistle classification conducted by eye with three computer methods using different similarity measures. Only the human observer classification was able to recognize whistle types that were used in a context- specific way by the animals confirming the power of this common classification method. Copying of signature whistles and whistle matching between animals was rare in captivity. However, observations of whistle interactions in the Moray Firth, Scotland, showed that wild dolphins do not tend to interact vocally in general, but that whistle matching was more frequent than expected by chance. Whistle matching in captivity was rare. Sound pressure measurements of dolphin whistles in the wild showed that source levels can reach up to 169 dB re 1 μPa and that the active space of a dolphin whistle can range up to 38 km. Finally, observations of foraging in wild dolphins revealed that they produce low frequency braying sounds in this context. Other dolphins would rapidly approach the caller in response to a bray. However, it is not clear whether brays function to attract conspecifics or manipulate prey behaviour

Studies of the flocking behaviour of Sanderlings

The behaviour of sanderlings, Calidris alba, was studied at Teesmouth, N. E. England. Flock sizes and within-flock spacing were related to factors such as substrate type, season, and prey distribution. Sightings of individually-identifiable colour-ringed birds showed that turnover was high. Individuals varied in their vagility and in the way in which they allocated their time between feeding sites. There was a high degree of consistency between winters in the distributions of individual birds. When individual sighting frequencies were taken into account, associations between individual sanderlings, in terms of both flock membership and of occurrences at the same sites on the same days, were non-significantly different from those expected by chance. Previously used methods for detecting non-random associations gave inadequate null models. Each individual appeared to make a decision about where to feed independently of the decisions made by any other particular individuals .A number of aspects of the dynamics of flocks were examined, including flock cohesion; how flocks built up and broke down; whether birds tended to move to the largest or smallest, the nearest or furthest flocks; the effects of disturbance on flock dynamics; and the relationship between group size and the distance flown between flocks. The responses of sanderlings to experimental disturbances tended to support the hypothesis that responses should be varied according to the costs and benefits of different courses of action rather than the hypothesis that birds should take flight as soon as a predator is sighted. Birds often break off from performing an activity in order to raise their heads (scan). Preening birds had shorter inter-scan intervals than feeding birds. Flock size and spacing explained only a small proportion of the variance in vigilance. Vigilance was greater in autumn than in winter. There was some evidence for both feeding and preening birds avoiding very short inter-scan intervals but not for the avoidance of long intervals. Sequences of inter-scan interval durations of preening birds were non-random