Data from: Predictable males and unpredictable females: repeatability of sociability in eastern water dragons

There is growing evidence for consistent among-individual variation in individual sociability (e.g., tendency to be sociable) in a number of species. However, sexes often differ in their social behaviors, as well as the selection pressures which they experience. This may translate into differences in repeatability of sociability, although this has not yet been tested. Here, we investigated whether eastern water dragons (Intellegama leseurii) exhibited evidence of consistent among-individual variation (i.e., repeatability) in 4 different measurements of sociability. Specifically, we measured sociability in 4 ways (degree, centrality, proportion of time spent being social, and number of preferences), and tested whether there was evidence for sex differences in the repeatability of these sociability measurements, or whether observed levels of repeatability could be explained by a stable social environment. Our findings provide new evidence for sex differences in social personality: we found that males were significantly repeatable in 3 of 4 sociability measurements (degree, centrality, and proportion of time spent being social), whereas females were not. Further, we found that these differences were not a result of differences in the dynamics of the social environment. We discuss our findings in the context of sexual selection, as well as sex differences in the evolutionary drivers of social behavior

Raw data_Strickland & Frere

Raw spatial data used for all analysis described in article entitled "Predictable males and unpredictable females: repeatability of sociability in eastern water dragons"

DolphinGenotypeData

Genotypes for 272 individual Tursiops aduncus at 4235 loc

SimulatedGenotypeData

Genotypes simulated using the program Conancestry (Wang 2011) for 100 pairs at each of 6 levels of relatedness. Allele frequencies and genotyping error are set to match those found in the real dolphin genotype data in the study

Cooperation and strategic complementarity: An experiment with two voluntary contribution mechanism games with interior equilibria

In public goods game experiments, designs implementing non-linearities in the production are less common than the standard linear setting, especially so under the assumption that the private goods production and public goods aggregation function are both non-linear. We study a voluntary contribution game (VCM) in which returns from the private project have diminishing marginal benefits and the contributions to the joint project exhibit pairwise strategic complementarities. As a control, we use a public goods game with an identical private production technology, but with the standard linear public goods aggregation. In addition to the aggregation technology, we manipulate the group size variable: In both treatments, the subjects will first play a VCM game in groups of five for 20 rounds, after which the group size is reduced to two, and the game is played for another 20 rounds. A significant over-contribution is observed in both settings when the group size is five. The rate of over-contribution is much higher under the complementary technology, but as predicted by theory, the contributions drop drastically when the group size is reduced from n = 5 to n = 2 within this treatment. Our experiment also provides empirical evidence that the so-called group size effect is present in both treatments, but it is much weaker under the standard aggregation technology

Quantifying koala locomotion strategies: implications for the evolution of arborealism in marsupials

ABSTRACTThe morphology and locomotor performance of a species can determine their inherent fitness within a habitat type. Koalas have an unusual morphology for marsupials, with several key adaptations suggested to increase stability in arboreal environments. We quantified the kinematics of their movement over ground and along narrow arboreal trackways to determine the extent to which their locomotion resembled that of primates, occupying similar niches, or basal marsupials from which they evolved. On the ground, the locomotion of koalas resembled a combination of marsupial behaviours and primate-like mechanics. For example, their fastest strides were bounding type gaits with a top speed of 2.78 m s−1 (mean 1.20 m s−1), resembling marsupials, while the relatively longer stride length was reflective of primate locomotion. Speed was increased using equal modification of stride length and frequency. On narrow substrates, koalas took longer but slower strides (mean 0.42 m s−1), adopting diagonally coupled gaits including both lateral and diagonal sequence gaits, the latter being a strategy distinctive among arboreal primates. The use of diagonally coupled gaits in the arboreal environment is likely only possible because of the unique gripping hand morphology of both the fore and hind feet of koalas. These results suggest that during ground locomotion, they use marsupial-like strategies but alternate to primate-like strategies when moving amongst branches, maximising stability in these environments. The locomotion strategies of koalas provide key insights into an independent evolutionary branch for an arboreal specialist, highlighting how locomotor strategies can convergently evolve between distant lineages.</jats:p

Data from: Quality and quantity of genetic relatedness data affect the analysis of social structure

Kinship plays a fundamental role in the evolution of social systems and is considered a key driver of group living. To understand the role of kinship in the formation and maintenance of social bonds, accurate measures of genetic relatedness are critical. Genotype-by-sequencing technologies are rapidly advancing the accuracy and precision of genetic relatedness estimates for wild populations. The ability to assign kinship from genetic data varies depending on a species’ or population’s mating system and pattern of dispersal, and empirical data from longitudinal studies are crucial to validate these methods. We use data from a long-term behavioral study of a polygynandrous, bisexually philopatric marine mammal to measure accuracy and precision of parentage and genetic relatedness estimation against a known partial pedigree. We show that with moderate but obtainable sample sizes of approximately 4235 SNPs and 272 individuals, highly accurate parentage assignments and genetic relatedness coefficients can be obtained. Additionally, we subsample our data to quantify how data availability affects relatedness estimation and kinship assignment. Lastly, we conduct a social network analysis to investigate the extent to which accuracy and precision of relatedness estimation improve statistical power to detect an effect of relatedness on social structure. Our results provide practical guidance for minimum sample sizes and sequencing depth for future studies, as well as thresholds for post hoc interpretation of previous analyses

Data from: Quality and quantity of genetic relatedness data affect the analysis of social structure

Kinship plays a fundamental role in the evolution of social systems and is considered a key driver of group living. To understand the role of kinship in the formation and maintenance of social bonds, accurate measures of genetic relatedness are critical. Genotype-by-sequencing technologies are rapidly advancing the accuracy and precision of genetic relatedness estimates for wild populations. The ability to assign kinship from genetic data varies depending on a species’ or population’s mating system and pattern of dispersal, and empirical data from longitudinal studies are crucial to validate these methods. We use data from a long-term behavioral study of a polygynandrous, bisexually philopatric marine mammal to measure accuracy and precision of parentage and genetic relatedness estimation against a known partial pedigree. We show that with moderate but obtainable sample sizes of approximately 4235 SNPs and 272 individuals, highly accurate parentage assignments and genetic relatedness coefficients can be obtained. Additionally, we subsample our data to quantify how data availability affects relatedness estimation and kinship assignment. Lastly, we conduct a social network analysis to investigate the extent to which accuracy and precision of relatedness estimation improve statistical power to detect an effect of relatedness on social structure. Our results provide practical guidance for minimum sample sizes and sequencing depth for future studies, as well as thresholds for post hoc interpretation of previous analyses

Australian Magpies Gymnorhina tibicen cooperate to remove tracking devices

Recent advances in tracking technology have enabled devices such as Global Positioning Systems (GPS) loggers to be used on a wide variety of birds. Although there are established ethical considerations to these processes, different species may react differently to particular devices and attachments. Thus, pilot studies are still of utmost importance in this field. Here, we describe one such study trialling a novel harness design for GPS tracking devices on Australian Magpies Gymnorhina tibicen. Despite previous testing demonstrating the strength and durability of the harness, devices were removed within minutes to hours of initial fitting. Notably, removal was observed to involve one bird snapping another bird’s harness at the only weak point, such that the tracker was released. This behaviour demonstrates both cooperation and a moderate level of problem solving, providing potential further evidence of the cognitive abilities of this species. To our knowledge, this is the first study to report the conspecific removal of GPS trackers, and should be considered when planning future tracking studies especially on highly social species.</jats:p