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Ex situ conservation breeding for species recovery often must address small founder number. Here we investigated the long‐term effects of small founder size in the endangered black‐footed ferret Mustela nigripes using 20 years of reproductive data. Specifically, we studied seminal traits, pregnancy success and litter size in the context of the population's low genetic diversity. Detailed evaluation of 539 electroejaculates from 262 pedigreed donors with varied inbreeding coefficients (F = 0.000–0.250) revealed a wide range in sperm motility (0.0–100.0%), forward progression (type of forward movement on a scale 0–5; 5 = best; 0.0–4.5), cell concentration (7.2–6348.0 × 106 mL−1 of ejaculate), structural normality (0.0–89.0%) and normal apical ridges (critical for fertilization; 4.8–100.0%). Over this two decade interval, there was an increase (P < 0.05) in F and a decrease (P < 0.05) in sperm forward progression and structurally normal cell morphology. From analysis of artificial insemination (AI) data, higher values for sperm motility, forward progression and structural normality or spermatozoa that retained a normal apical ridge had a positive influence (P < 0.05) on litter size. Males producing higher values for these four traits also sired more kits. Results demonstrate that sperm motility and morphology are decreasing in black‐footed ferrets managed intensively ex situ. These two metrics appear associated with an increasing F and likely are at least partially responsible for lowered reproductive success in this closed, endangered population. These results illustrate the potential physiological and offspring production impact of having few founders available in an ex situ conservation breeding program. [ABSTRACT FROM AUTHOR]

The study of social learning in non-human animals has advanced beyond attempts to determine which animals are capable of learning socially to investigations of the factors that influence transmission. Capuchin monkeys (Sapajus sp.) are adept social learners of various behaviours including extractive foraging techniques and social customs. Here, we conducted an open diffusion experiment to determine whether capuchins would learn an arbitrary convention from a knowledgeable demonstrator. In addition, we investigated whether rank, sex and social context affected acquisition and expression of the behaviour. Participation in the experiment was strongly influenced by dominance rank in the group setting. However, when tested individually, the majority of individuals participated and faithfully copied the convention that was seeded into their group. Our findings demonstrate that capuchins can acquire an arbitrary convention via social learning, but that social context must be carefully considered in studies of social learning. [ABSTRACT FROM AUTHOR]

Wild chimpanzees routinely share high-value resources such as meat obtained through hunting and fruit procured from raiding crops. Although it is predicted that the proximate mechanisms for sharing behaviour are the result of reciprocity, interchange and mutualism, examinations of these factors in captivity have not mirrored the degree to which they are found in the wild. The goal of the current study was to investigate how a group of seven captive chimpanzees responded when a highly desirable and monopolizable resource diminished over the course of eight months. To do this we measured the amount of time that was spent sharing food at an artificial termite mound as well as the relationship between dyads that spent time sharing. Our results contradicted our predictions that rates of aggression would increase and the number of individuals fishing at the termite mound would decrease when resources diminished, as we observed no difference in either variable over time. We did, though, find an increase in the amount of sharing as the number of baited holes decreased. We also found a correlation between the strength of dyadic relationships outside of the study and the amount of time that individuals spent sharing with each other. [ABSTRACT FROM AUTHOR]

Although there are published reports of wild chimpanzees, bonobos, and orangutans hunting and consuming vertebrate prey, data pertaining to captive apes remain sparse. In this survey-based study, we evaluate the prevalence and nature of interactions between captive great apes and various indigenous wildlife species that range into their enclosures in North America. Our hypotheses were threefold: (a) facilities housing chimpanzees will report the most frequent and most aggressive interactions with local wildlife; (b) facilities housing orangutans and bonobos will report intermediate frequencies of these interactions with low levels of aggression and killing; and (c) facilities housing gorillas will report the lowest frequency of interactions and no reports of killing local wildlife. Chimpanzees and bonobos demonstrated the most aggressive behavior toward wildlife, which matched our predictions for chimpanzees, but not bonobos. This fits well with expectations for chimpanzees based on their natural history of hunting and consuming prey in wild settings, and also supports new field data on bonobos. Captive gorillas and orangutans were reported to be much less likely to chase, catch and kill wildlife than chimpanzees and bonobos. Gorillas were the least likely to engage in aggressive interactions with local wildlife, matching our predictions based on natural history. However unlike wild gorillas, captive gorillas were reported to kill (and in one case, eat) local wildlife. These results suggest that some behavioral patterns seen in captive groups of apes may be useful for modeling corresponding activities in the wild that may not be as easily observed and quantified. Furthermore, the data highlight the potential for disease transmission in some captive settings, and we outline the associated implications for ape health and safety. Am. J. Primatol. 71:458–465, 2009. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Understanding the rates and causes of mortality in wild chimpanzee populations has important implications for a variety of fields, including wildlife conservation and human evolution. Because chimpanzees are long-lived, accurate mortality data requires very long-term studies. Here, we analyze 47 years of data on the Kasekela community in Gombe National Park. Community size fluctuated between 38 and 60, containing 60 individuals in 2006. From records on 220 chimpanzees and 130 deaths, we found that the most important cause of mortality in the Kasekela community was illness (58% of deaths with known cause), followed by intraspecific aggression (20% of deaths with known cause). Previous studies at other sites also found that illness was the primary cause of mortality and that some epidemic disease could be traced to humans. As at other study sites, most deaths due to illness occurred during epidemics, and the most common category of disease was respiratory. Intraspecific lethal aggression occurred within the community, including the killing of infants by both males and females, and among adult males during the course of dominance-related aggression. Aggression between communities resulted in the deaths of at least five adult males and two adult females in the Kasekela and Kahama communities. The frequency of intercommunity violence appears to vary considerably among sites and over time. Intercommunity lethal aggression involving the Kasekela community was observed most frequently during two periods. Other less common causes of death included injury, loss of mother, maternal disability, and poaching. Am. J. Primatol. 70:766–777, 2008. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Understanding the local and regional patterns of species distributions has been a major goal of ecological and evolutionary research. The notion that these patterns can be understood through simple quantitative rules is attractive, but while numerous scaling laws exist (e.g., metabolic, fractals), we are aware of no studies that have placed individual traits and community structure together within a genetics based scaling framework. We document the potential for a genetic basis to the scaling of ecological communities, largely based upon our long-term studies of poplars (Populus spp.). The genetic structure and diversity of these foundation species affects riparian ecosystems and determines a much larger community of dependent organisms. Three examples illustrate these ideas. First, there is a strong genetic basis to phytochemistry and tree architecture (both above- and belowground), which can affect diverse organisms and ecosystem processes. Second, empirical studies in the wild show that the local patterns of genetics based community structure scale up to western North America. At multiple spatial scales the arthropod community phenotype is related to the genetic distance among plants that these arthropods depend upon for survival. Third, we suggest that the familiar species–area curve, in which species richness is a function of area, is also a function of genetic diversity. We find that arthropod species richness is closely correlated with the genetic marker diversity and trait variance suggesting a genetic component to these curves. Finally, we discuss how genetic variation can interact with environmental variation to affect community attributes across geographic scales along with conservation implications.Heredity (2008) 100, 121–131; doi:10.1038/sj.hdy.6800914; published online 18 October 2006 [ABSTRACT FROM AUTHOR]

The evolutionary analysis of community organization is considered a major frontier in biology. Nevertheless, current explanations for community structure exclude the effects of genes and selection at levels above the individual. Here, we demonstrate a genetic basis for community structure, arising from the fitness consequences of genetic interactions among species (i.e., interspecific indirect genetic effects or IIGEs). Using simulated and natural communities of arthropods inhabiting North American cottonwoods (Populus), we show that when species comprising ecological communities are summarized using a multivariate statistical method, nonmetric multidimensional scaling (NMDS), the resulting univariate scores can be analyzed using standard techniques for estimating the heritability of quantitative traits. Our estimates of the broad-sense heritability of arthropod communities on known genotypes of cottonwood trees in common gardens explained 56-63% of the total variation in community phenotype. To justify and help interpret our empirical approach, we modeled synthetic communities in which the number, intensity, and fitness consequences of the genetic interactions among species comprising the community were explicitly known. Results from the model suggest that our empirical estimates of broad-sense community heritability arise from heritable variation in a host tree trait and the fitness consequences of IGEs that extend from tree trait to arthropods. When arthropod traits are heritable, interspecific IGEs cause species interactions to change, and community evolution occurs. Our results have implications for establishing the genetic foundations of communities and ecosystems. [ABSTRACT FROM AUTHOR]