Reproductive behaviour and aspects of group dynamics in the genus Acomys were studied in the respect to the individuals? physical condition, life history traits and social environment. Three of the presented studies reveal the important effect of social environment on the behaviour of group members to the new-coming male and reproductive behaviour of females (sex ratio of the pups and litter size). The other two studies investigate the costs associated with group living and cooperative breeding in Sinai spiny mice and the factors influencing alloparental behaviour. Results of this Ph.D. thesis reveal several aspects of social and reproductive behaviour of group-living mammals and contribute to the understanding of the formation and maintenance of the societies in general.

Dispersal is a critical life-history component; it determines gene flow and has profound effects on population structure, demography, social systems, and population viability. To add to our knowledge of dispersal and, in particular, our understanding of the relationship between dispersal and inbreeding, I studied three aspects of the biology of the red-cockaded woodpecker: dispersal of breeding females; the costs, benefits, and frequency of inbreeding; and the effect of inbreeding on natal dispersal. Dispersal of breeding female red-cockaded woodpeckers is strongly associated with inbreeding avoidance and mate choice, weakly associated with site choice, and not found to be associated with social constraints. Estimates of mortality for non-dispersing and dispersing breeding females were 24 and 59 percent per year, respectively-rare evidence of the cost of breeding dispersal. Significant costs of close inbreeding were found. Closely related pairs (kinship coefficient greater than 0.1) had lower hatching success as well as lower survival and recruitment of fledglings than unrelated pairs. Moderately related pairs (kinship coefficient between 0 and 0.1) and moderately inbred individuals had increased hatching success, but did not produce more young. Despite documented costs of close inbreeding and a predictable spatial distribution of closely related males near the natal territory, female fledglings disperse a median of only two territories and a modal distance of one territory. Natal dispersal of females is affected by closely related males on the natal site but unaffected by closely related males or moderately related males that are off the natal site. / Master of Science

Cooperatively breeding societies, in which one or more non-parental individuals (“alloparents”) care for young alongside the parents, show considerable variation in social structure. Traditionally, such societies have been thought to comprise small, kin-based family groups where offspring from previous broods delay dispersal and help raise closely-related offspring to gain indirect fitness benefits when independent breeding opportunities are unavailable or yield lower fitness outcomes. However, genetic evidence is increasingly revealing cooperatively breeding species whose social groups comprise unrelated individuals as co-breeders or alloparents or both (for e.g., 45% of all avian cooperative breeders). Such social groups exhibit complexity in social structure such as large group size, multiple breeders, and low and varied group kin structure. To understand why such complex societies form and how are they maintained when the opportunity to gain indirect benefits via kin selection is low and variable, I investigated the direct and indirect benefits driving a key demographic process, dispersal, and the resulting variation in group social structure on the individual, group, and population levels in an obligate, avian cooperative breeder, the superb starling (Lamprotornis superbus). I used a combination of long-term, individual-level data spanning 15 years from nine groups monitored at the Mpala Research Centre in Kenya and fine-scale genetic and environmental data sampled across 22 social groups that included the long-term study population. In Chapter 1, I show that (i) dispersal decisions in superb starling males are driven by temporal environmental variation experienced by their parents pre-laying, (ii) both dispersal and philopatry result in equivalent lifetime inclusive fitness outcomes, and (iii) oscillating selection due to high temporal variability in the environment likely maintains the two alternative dispersal tactics, resulting in the formation of mixed-kin groups. In Chapter 2, I show that (i) immigrants are vital to the stability of superb starling social groups in light of low and variable offspring recruitment in a harsh, unpredictable environment, (ii) plural breeding likely arises as a result of reproductive concessions provided by group members as joining incentives to recruit immigrants, and (iii) despite smaller groups providing more reproductive concessions, immigrants gain higher fitness in larger social groups and thus prefer to immigrate into larger groups which are found in higher-quality territories. Finally, in Chapter 3, I find genetic signatures of directional dispersal from social groups in low- to high-quality territories across an environmental gradient which likely generates considerable within-population variation in group social structure. Overall, my dissertation underscores the importance of direct benefits derived from group augmentation in the formation and maintenance of cooperative social groups with a complex social structure in a harsh and unpredictable environment.

<p>I studied acoustic and visual communication in the Smooth-billed Ani, a joint-nesting, cooperatively breeding cuckoo. I describe vocal repertoire of this species using both qualitative and quantitative methods. In this first, formal description of the species’ repertoire, I provide verbal descriptions of each call type, the contexts in which each call is produced, spectrograms, and acoustic measurements for each call type. I used multivariate statistics to show that call types can be correctly classified based on acoustic measurements alone. Smooth-billed Anis are capable of complex communication, including the use of functionally referential alarms and signals of aggression that reliably predict attack. Functionally referential signals are produced in response to a specific set of stimuli and elicit predictable, appropriate responses in signal receivers, even in the absence of any other cues. I show that anis produce two distinct signal types, <em>chlurps</em> and <em>ahnee</em> <em>alarms</em>, in response to two different predator classes, aerial and terrestrial, respectively. I also show that receiver responses to playback of these alarm signals are distinct and appropriate to evade predation from aerial and terrestrial attackers. Aggressive signals should increase in aggressive contexts, predict subsequent aggression and elicit responses from signal receivers. I show that <em>hoots</em>, an acoustic signal, and throat inflation, a visual signal, both increase in aggressive contexts and reliably predict aggressive escalation in the form of direct attacks on a mount. The receiver response to <em>hoots</em> and throat inflation remains to be tested. In the synthesis, I provide suggestions for future research.</p> / Master of Science (MSc)

Group living is a widespread social system among animals. Within these groups, decisions on interactions between individuals can be facilitated through knowledge about individual identity and kinship. Individual identity allows for the recognition of individuals from past interactions and thus, information on likelihood of reciprocity and group-membership can be gained. The benefit for cooperative interactions, specifically, increases with the level of relatedness between the helper and the recipient. Thus, knowing who is kin, is an essential ability among group-living species and remembering individual identity helps to maintain long-term relationships and inform future decisions. Kin recognition can be facilitated through temporal and spatial overlap (i.e. familiarity) or through phenotypic-templates (i.e. phenotype matching). The goal of this thesis was to explore recognition in the joint-nesting pūkeko (Porphyrio melanotus melanotus). For the first portion of this thesis (Chapter II), I tested for evidence of phenotype matching in pūkeko using a cross-fostering experiment. Comparing survival and growth between fostered and non-fostered offspring, I provide evidence that pūkeko do not use phenotype matching as their mechanism for kin recognition. In Chapter III, I show that pūkeko chick distress calls may have an individual and group signature. I found variation in the vocal parameters between individual chicks and social groups. I also tested for response of adults towards chick distress calls of their own group. Using a playback-choice experiment, I report a biased response of adult pūkeko towards the distress call of their own group's chicks rather than the call of a distressed chick from a foreign chick. / Thesis / Master of Science (MSc) / Kin recognition is an essential ability for social species. Knowing whom is kin can help inform decisions on cooperation and conflict. I explored whether the joint-nesting pūkeko use familiarity or phenotype matching to recognise cross-fostered offspring. I experimented to determine if adult pūkeko can recognise the distress vocalizations of chicks in their group. I found no evidence that pūkeko use phenotypic templates to recognise cross-fostered chicks as non-kin. However, adult pūkeko showed a bias in response towards the distress calls of their own versus unfamiliar chicks. Individual chick distress calls, while variable from day-to-day, show group-specific similarities.

One unresolved issue in the study of cooperative breeding is why individuals that delay their own reproduction assist others in raising young. Red-cockaded woodpecker helpers may again future indirect fitness benefits by increasing survival of breeders, who produce offspring related to the helper in the future. Breeder survival may be enhanced because of general benefits of group living, either because of the helper's own presence or because helping increases the production of fledglings. I demonstrate that breeder survival increases in the presence of helpers and additional young. Helpers may also reduce the workload of the breeder, and this may increase breeder survival as well. I show that breeders spend less time incubating and provisioning young when a helper is present. Helpers may also gain fitness benefits if once they become breeders, they are assisted by young they previously helped raise. Expected frequencies of reciprocal exchange of helping are low (2%). Slightly higher observed frequencies may be accounted for by preferential helping of kin and effects of territory quality. Reciprocity occurs no more often than expected among helpers unrelated to the young they help raise suggesting that young males do not preferentially helper former care-givers. i conclude that helpers do not gain fitness benefits from reciprocity. I examined the proximate causes of delayed breeding and helping behavior by measuring plasma testosterone (T) and prolactin (PRL) concentrations in female breeders, male breeders, and male helpers during different stages of the reproductive cycle. Among male breeders and helpers, T is low during the nonbreeding stage, peaks during copulation and declines during the incubation and nestling-provisioning stages. Helpers appear physiologically capable of reproducing: their T concentrations are equal those of breeders. Helpers unrelated to the breeding female have higher T than helper related to her. Sexual inactivity by male helpers is best explained by behavioral suppression. Female breeder, male breeder, and male helper PRL was equal and increased from the nonbreeding stage through the copulation and incubation stages. During the nestling provisioning stage, male breeder and male helper PRL declined, while female PRL continued to increase. I conclude that the physiological bases of helping behavior and parental behavior are the same. / Ph. D.

Made available in DSpace on 2014-12-17T15:37:23Z (GMT). No. of bitstreams: 1 FernandaHRC.pdf: 1074214 bytes, checksum: a491c48f14137c54d61720cb92efef5a (MD5) Previous issue date: 2007-09-21 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The Callitrichidae family presents cooperative breeding, where breeders and non breeders take care of the offspring. The aspects of care analyzed in this study were infant carrying, supervision, proximity and food transfer. Three sets of infants from two wild groups of Callithrix jacchus were studied in the environments of Caatinga (Assu group) and Atlantic Forest (Jundia? group). The methods used in the study were instantaneous focal sampling (infant carrying, supervision and proximity) and continuous focal sampling (food transfer). In the two sets observed in Assu group, the father carried and transferred food to infants more than the rest of the group. The biggest contribution in supervision was from the father and from another adult male. The members that remained in proximity to the infants in both groups were the younger in the groups (juveniles and sub-adults). In the Jundia? group, the father and the adult male helper of the group were the main caregivers; one of the sub-adult females was responsible for supervision of the infants. With the disappearance of the reproductive male and one of the sub-adults females in 3? month of infants life, the care was redistributed and the only adult male left in the group was the animal that contributed more in provisioning of the infant. In the Assu group, there were adult females in its composition which were involved in agonistic interactions with breeders and adult males, and seemed to influence their low participation in care. Food transfer initiates early in the development of the infants, as a way to encourage nutritional independence. Different types of food transfer (active food transfer, food steal, food steal attempt, passive food transfer and food handling) were observed in the study and frequency of each one varied with developmental phase and tolerance by the members. One relevant data of the study was the presence of active food transfer in Assu group, since in literature there are very few registers of this type of transfer for this species. It is important that groups from distinct environments and composition be studied for a better understanding of the dynamics of infants development / A fam?lia Callitrichidae apresenta um sistema de cuidado cooperativo, onde os reprodutores e n?o reprodutores cuidam da prole. Os aspectos do cuidado ? prole analisados neste estudo foram o transporte dos infantes, a supervis?o, a proximidade e as transfer?ncias de alimento. Foram estudados dois grupos de Callithrix jacchus silvestres em ambientes de Caatinga (Grupo de Assu) e de Floresta Atl?ntica (Grupo de Jundia?). Os m?todos utilizados foram animal focal (transporte do infante, supervis?o e proximidade) e o focal cont?nuo (transfer?ncia de alimento). Nas duas proles observadas no grupo de Assu, o indiv?duo que mais contribuiu no transporte dos filhotes e no provisionamento dos infantes foi o pai. A maior contribui??o na supervis?o de uma prole foi do pai e na outra de um macho adulto. Os membros mais pr?ximos dos infantes nos dois grupos foram os animais de faixas et?rias mais pr?ximas (juvenis e sub-adultos). Na ?nica prole do grupo de Jundia? observada, o pai e o ?nico ajudante macho adulto do grupo foram os principais carregadores dos filhotes e uma das f?meas sub-adultas, a principal respons?vel pela supervis?o dos infantes. Com o desaparecimento do macho reprodutor e uma das f?meas sub-adultas no 3? m?s de vida dos infantes, o cuidado foi redistribu?do e o ?nico macho adulto foi o que mais contribuiu no provisionamento do infante. O grupo de Assu apresentava f?meas adultas em sua composi??o e nele ocorreram mais intera??es agon?sticas entre estas f?meas adultas com os reprodutores e machos adultos, o que refletiu a baixa freq??ncia de ajuda deste sexo-idade. A transfer?ncia de alimento inicia cedo no desenvolvimento dos filhotes como maneira de encorajar a independ?ncia nutricional. Diversos tipos de transfer?ncia de alimento (transfer?ncia ativa, roubo, tentativa de roubo, transfer?ncia passiva e manipula??o do alimento) foram observados no estudo e a freq??ncia de cada um variou de acordo com o est?gio de desenvolvimento do infante e com a toler?ncia dos membros do grupo. Um dado relevante do estudo foi a presen?a de transfer?ncia ativa de alimento no grupo de Assu, j? que na literatura existem poucos registros deste tipo de transfer?ncia para esta esp?cie. ? interessante que grupos de ambientes e composi??o distintos sejam estudados para uma melhor compreens?o da din?mica das transfer?ncias de alimento na natureza

Maximiser le nombre de copies de gènes transmises aux générations suivantes implique une série de compromis. Chez les espèces à reproduction coopérative, des individus ne se reproduisent pas mais participent aux soins des jeunes d'autres individus reproducteurs. Ces assistants sont particulièrement intéressants dans le contexte des traits d'histoire de vie car ils forment un environnement prédictible favorable pour la reproduction, et leur présence peut aussi influencer les compromis évolutifs chez les reproducteurs. Un compromis évolutif majeur mais sous-étudié dans le cadre de la reproduction coopérative est l'allocation maternelle notamment via des effets maternels qui sont des modifications épigénétiques du phénotype de la descendance. Nous avons étudié l'existence d'effets maternels associés à la présence d'assistants et leurs possibles conséquences sur les femelles et leurs descendants chez un oiseau colonial et coopératif du sud de l'Afrique, le Républicain social Philetairus socius. Nos résultats montrent que les femelles pondent des œufs plus légers en présence d'assistants et que ces œufs sont moins concentrés en corticostérone et testostérone. Nos résultats montent aussi une plus grande probabilité de survie pour les femelles se reproduisant en groupe pouvant être en partie due à leur plus faible investissement dans les œufs. De plus, l'étude de la température dans les nids en fonction de la taille des groupes a permis de suggérer d'autres bénéfices pour les parents et assistants, en particulier via une réduction des coûts de thermorégulation qui pourrait aussi permettre de garder de l'énergie pour la survie. Pour comprendre les conséquences de la présence d'assistants et de l'allocation différentielle pour les poussins, une expérience d'adoption croisée a été réalisée. Elle a révélé que les œufs pondus par les femelles avec plus d'assistants produisent des poussins qui quémandent moins, montrant que des effets maternels pourraient influencer le comportement des poussins. Enfin nous avons étudié la survie des poussins après l'envol à l'aide d'analyses de captures recaptures et avons trouvé de manière surprenante que les poussins à l'envol ont une probabilité de survie plus faible lorsqu'ils sont élevés présence d'assistants. Ces résultats dans leur ensemble démontrent l'importance d'étudier les effets maternels chez les espèces coopératives et ouvrent de nombreuses perspectives de recherche sur les conflits familiaux et de compromis évolutifs associés à la présence d'assistants. / Maximizing of the number copies of genes that are transmitted to the next generations involves a series of tradeoffs. In cooperatively breeding species some sexually mature individuals do not breed but instead help other individuals to raise their offspring. These helpers are particularly interesting in a life history context as they create a predictably favorable breeding environment and their presence can thus influence evolutionary trade-offs. A major evolutionary trade-off that is often neglected in studies on cooperative breeding is maternal allocation, notably through maternal effects that are epigenetic modifications of offspring phenotype. Here we investigate whether there are maternal effects induced by the presence of helpers and their possible consequences on females and their offspring in a colonial cooperative breeder of southern Africa, the sociable weaver Philetairus socius. Our results show that females lay smaller eggs in the presence of helpers and in addition these eggs have lower corticosterone and testosterone concentrations. Our results also show a higher survival probability of females breeding in groups, which may be partially due to their lower investment in eggs. In addition, a study of roosting chamber temperatures in relation to group size suggests further benefits for parents and helpers, particularly through lower costs of thermoregulation that could also allow energy savings for survival. To start understanding the consequences of helpers presence and differential maternal allocation for offspring we conducted a cross fostering experiment. Our results show that eggs produced by females breeding in larger groups produce chicks that beg at a lower rate, showing that maternal effects may influence chicks' behavior. Finally, we investigated post-fledging survival through capture-recapture analyses and, surprisingly, found that fledglings have a lower survival probability when raised with helpers. Taken together, these results demonstrate the importance of studying maternal effects on cooperative breeders and open several research prospects on family conflicts and life history trade-offs according to the presence of helpers.

No description available.

I confronted empirical habitat data (1994-2004) and population data (1988-2005) with ecological theory on habitat dynamics, recruitment, survival, and dispersal to develop predictive relationships between landcover variation and population dynamics. I focus on Florida Scrub-Jays, although one chapter presents a model for the potential influence of habitat restoration on viability of the Florida Grasshopper Sparrow. Both species are unique to Florida landscapes that are dominated by shrubs and grasses and maintained by frequent fires. Both species are declining, even in protected areas, despite their protected status. I mapped habitat for both species using grid polygon cells to quantify population potential and habitat quality. A grid cell was the average territory size and the landcover unit in which habitat-specific recruitment and survival occurred. I measured habitat-specific recruitment and survival of Florida Scrub-Jays from 1988-2008. Data analyses included multistate analysis, which was developed for capture-recapture data but is useful for analyzing many ecological processes, such as habitat change. I relied on publications by other investigators for empirical Florida Grasshopper Sparrow data. The amount of potential habitat was greatly underestimated by landcover mapping not specific to Florida Scrub-Jays. Overlaying east central Florida with grid polygons was an efficient method to map potential habitat and monitor habitat quality directly related to recruitment, survival, and management needs. Most habitats for both species were degraded by anthropogenic reductions in fire frequency. Degradation occurred across large areas. Florida Scrub-Jay recruitment and survival were most influenced by shrub height states. Multistate modeling of shrub heights showed that state transitions were influenced by vegetation composition, edges, and habitat management. Measured population declines of 4% per year corroborated habitat-specific modeling predictions. Habitat quality improved over the study period but not enough to recover precariously small populations. The degree of landcover fragmentation influenced mean Florida Scrub-Jay dispersal distances but not the number of occupied territories between natal and breeding territories. There was little exchange between populations, which were usually further apart than mean dispersal distances. Florida Scrub-Jays bred or delayed breeding depending on age, sex, and breeding opportunities. I show an urgent need also for Florida Grasshopper Sparrow habitat restoration given that the endangered bird has declined to only two sizeable populations and there is a high likelihood for continued large decline. A major effect of habitat fragmentation identified in this dissertation that should apply to many organisms in disturbance prone systems is that fragmentation disrupts natural processes, reducing habitat quality across large areas. Humans have managed wildland fire for > 40,000 years, so it should be possible to manage habitat for many endangered species that make Florida's biodiversity unique. This dissertation provides methods to quantify landscape units into potential source and sink territories and provides a basis for applying adaptive management to reach population and conservation goals.