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Science (New York, N.Y.) Jul 2015
Comparative Study
Topics: Animals; Biological Evolution; Brain; DNA; Enhancer Elements, Genetic; GTPase-Activating Proteins; Gene Dosage; Genes, Regulator; Genetic Engineering; Genome, Human; Humans; Mice; Mutagenesis, Insertional; Organ Size; Pan troglodytes; Receptors, Cell Surface; Species Specificity
PubMed: 26138961
DOI: 10.1126/science.349.6243.21 -
Psychological Science Mar 2023Risk preference impacts how people make key life decisions related to health, wealth, and well-being. Systematic variations in risk-taking behavior can be the result of...
Risk preference impacts how people make key life decisions related to health, wealth, and well-being. Systematic variations in risk-taking behavior can be the result of differences in fitness expectations, as predicted by life-history theory. Yet the evolutionary roots of human risk-taking behavior remain poorly understood. Here, we studied risk preferences of chimpanzees (86 ; 47 females; age = 2-40 years) using a multimethod approach that combined observer ratings with behavioral choice experiments. We found that chimpanzees' willingness to take risks shared structural similarities with that of humans. First, chimpanzees' risk preference manifested as a traitlike preference that was consistent across domains and measurements. Second, chimpanzees were ambiguity averse. Third, males were more risk prone than females. Fourth, the appetite for risk showed an inverted-U-shaped relation to age and peaked in young adulthood. Our findings suggest that key dimensions of risk preference appear to emerge independently of the influence of human cultural evolution.
Topics: Animals; Female; Humans; Male; Pan troglodytes; Risk-Taking; Biological Evolution
PubMed: 36595467
DOI: 10.1177/09567976221140326 -
American Journal of Biological... Sep 2023Morphological intraspecific variation is due to the balance between skeletal plasticity and genetic constraint on the skeleton. Osteogenic responses to external stimuli,...
OBJECTIVES
Morphological intraspecific variation is due to the balance between skeletal plasticity and genetic constraint on the skeleton. Osteogenic responses to external stimuli, such as locomotion, have been well documented interspecifically across the primate order, but less so at the intraspecific level. Here, we examine the differences in cross-sectional variability of the femur, humerus, radius, and tibia in Pan troglodytes troglodytes versus Gorilla gorilla gorilla. We investigate whether there are sex, species, bone, and trait differences in response to variable body size and locomotion.
MATERIALS AND METHODS
Adult male and female P. t. troglodytes and G. g. gorilla long bones from the Cleveland Museum of Natural History were scanned with a peripheral quantitative computer tomography system. Scans were taken at the midshaft of each bone according to functional bone length. Coefficients of variation were used to provide a size-independent measure of variation. We applied a Bonferroni correction to account for the multiple pairwise tests.
RESULTS
There were limited significant differences between males and females, however, females tended to be more variable than males. Variation in Gorilla, when significant, was greater than in Pan, although significant differences were limited. There were no differences between bone variability in male and female Gorilla, and female Pan.
DISCUSSION
Increased female variability may be due to more variable locomotor behavior, particularly during periods of pregnancy, lactation, and caring for an offspring compared to consistent locomotion over the life course by males. Body size may be a contributing factor to variability; more work is needed to understand this relationship.
Topics: Animals; Male; Female; Gorilla gorilla; Pan troglodytes; Hominidae; Bone and Bones; Locomotion
PubMed: 37504383
DOI: 10.1002/ajpa.24823 -
Proceedings of the National Academy of... Aug 2022
Topics: Aggression; Animals; Hostility; Pan paniscus; Pan troglodytes; Territoriality
PubMed: 35881798
DOI: 10.1073/pnas.2208865119 -
Current Biology : CB Jul 2014The role that genes play in human intelligence or IQ has remained a point of significant scientific debate dating back to the time of Galton [1]. It has now become...
The role that genes play in human intelligence or IQ has remained a point of significant scientific debate dating back to the time of Galton [1]. It has now become increasingly clear that IQ is heritable in humans, but these effects can be modified by nongenetic mechanisms [2-4]. In contrast to human IQ, until recently, views of learning and cognition in animals have largely been dominated by the behaviorist school of thought, originally championed by Watson [5] and Skinner [6]. A large body of accumulated research now demonstrates a variety of cognitive abilities in nonhuman animals and challenges traditional behaviorist interpretations of performance [7, 8]. This, in turn, has led to a renewed interest in the role that social and biological factors might play in explaining individual and phylogenetic differences in cognition [9]. Specifically, aside from early attempts to selectively breed for learning skills in rodents [10-12], studies examining the role that genetic factors might play in individual variation in cognitive abilities in nonhuman animals, particularly nonhuman primates, are scarce. Here, we utilized a modified Primate Cognitive Test Battery [13] in conjunction with quantitative genetic analyses to examine whether cognitive performance is heritable in chimpanzees. We found that some but not all cognitive traits were significantly heritable in chimpanzees. We further found significant genetic correlations between different dimensions of cognitive functioning, suggesting that the genes that explain the variability of one cognitive trait might also explain that of other cognitive traits.
Topics: Animals; Cognition; Female; Intelligence; Intelligence Tests; Learning; Male; Pan troglodytes; Principal Component Analysis
PubMed: 25017206
DOI: 10.1016/j.cub.2014.05.076 -
Cell Oct 2015LINE retrotransposons actively shape mammalian genomes. Denli et al. reveal a new open reading frame, ORF0, on the antisense strand of human LINE-1 encoding a small...
LINE retrotransposons actively shape mammalian genomes. Denli et al. reveal a new open reading frame, ORF0, on the antisense strand of human LINE-1 encoding a small regulatory protein. This finding may represent the birth of an emerging retrotransposon gene that can adopt various fates, as it can be fused to adjacent host sequences.
Topics: Animals; Humans; Pan troglodytes; Retroelements
PubMed: 26496595
DOI: 10.1016/j.cell.2015.10.033 -
Biological Reviews of the Cambridge... Nov 2018After 40 years of debate it remains unclear whether signallers produce vocalizations in order to provide receivers with information about call context or external... (Review)
Review
After 40 years of debate it remains unclear whether signallers produce vocalizations in order to provide receivers with information about call context or external stimuli. This has led some researchers to propose that call production is arousal- or affect-based. Although arousal influences certain acoustic parameters within a call type, we argue that it cannot explain why individuals across vertebrates produce different call types. Given emerging evidence that calls are goal-based, we argue that call type is a signal of a caller's goal to elicit a change in receiver behaviour. Using chimpanzees (Pan troglodytes) and vervet monkeys (Cercopithecus aethiops) as case studies, we demonstrate the two benefits of viewing call production as signalling both caller goal (which determines call type) and caller arousal (which affects within-call-type variation). Such a framework can explain first, why a single class of calls is apparently given in multiple contexts, and, second, why some species have larger call repertoires than others. Previous studies have noted links between sociality and repertoire size, but have not specified exactly why animals living in societies that are more complex might require a greater number of differentiated signals. The caller-goal framework potentially clarifies how social complexity might favour call diversification. As social complexity increases, callers may need to elicit a larger number of distinct behaviours from a wider range of distinct audiences.
Topics: Animals; Chlorocebus aethiops; Pan troglodytes; Social Behavior; Vocalization, Animal
PubMed: 29896860
DOI: 10.1111/brv.12437 -
Current Biology : CB Feb 2018For humans, there appears to be a clear link between general intelligence and self-control behavior, such as sustained delay of gratification [1-9]. Chimpanzees also...
For humans, there appears to be a clear link between general intelligence and self-control behavior, such as sustained delay of gratification [1-9]. Chimpanzees also delay gratification [10-12] and can be given tests of general intelligence (g) [13-15], but these two constructs have never been compared within the same sample of nonhuman animals. We presented 40 chimpanzees with the hybrid delay task (HDT) [16, 17], which measures inter-temporal choices and the capacity for sustained delay of gratification, and the primate cognitive test battery (PCTB), which measures g in chimpanzees [13-15]. Importantly, none of the sub-tasks in the PCTB directly assesses self-control or other forms of behavioral inhibition. Rather, they assess areas of physical cognition (e.g., quantity discrimination) or social cognition (e.g., gaze following). In three phases of testing, we consistently found that the strongest relation was between chimpanzee g scores and efficiency in the HDT. Chimpanzee g was not most closely related to the proportion of trials the chimpanzees chose to try to wait for delayed rewards, but rather most closely related to how good they were at waiting for those rewards when they chose to do so. We also found the same strong relation between HDT efficiency and those factors in the PCTB that loaded most strongly on chimpanzee g. These results highlight that, as with humans, there is a strong relation between chimpanzees' self-control and overall intelligence-a relation that likely reflects the role of successful inhibitory control during cognitive processing of information and intelligent decision-making.
Topics: Animals; Choice Behavior; Female; Intelligence; Male; Pan troglodytes; Reward; Self-Control; Social Behavior
PubMed: 29429613
DOI: 10.1016/j.cub.2017.12.043 -
Scientific Reports Jul 2018In wild animal conservation, knowing the age of an individual animal is extremely beneficial. However, estimating the age is difficult for many species. Recently,...
In wild animal conservation, knowing the age of an individual animal is extremely beneficial. However, estimating the age is difficult for many species. Recently, epigenetics-based methods of estimating age have been reported. These studies were predominantly on humans with few reports on other animals, especially wild animals. In the present study, a chimpanzee (Pan troglodytes) age prediction model was developed based on the ELOVL2, CCDC102B, and ZNF423 genes that may also have application in human age prediction. Pyrosequencing was used to measure methylation in 20 chimpanzee blood samples and correlation between age and methylation status was calculated. Age and methylation of sites in ELOVL2 and CCDC102B were significantly correlated and an age prediction model was created using these genes. In the regression equation using only ELOVL2, the highest correlation coefficient was 0.741, with a mean absolute deviation (MAD) of 5.41, compared with the combination of ELOVL2 and CCDC102B, where the highest correlation coefficient was 0.742 and the MAD was 5.41. Although larger MADs were observed in chimpanzees than in humans based on these genes, the results indicate the feasibility of estimating chimpanzee age using DNA methylation, and can have implications in understanding the ecology of chimpanzees and chimpanzee conservation.
Topics: Age Factors; Animals; CpG Islands; DNA Methylation; Epigenesis, Genetic; Epigenomics; Forecasting; Forensic Genetics; Pan troglodytes; Sequence Analysis, DNA
PubMed: 29968770
DOI: 10.1038/s41598-018-28318-9 -
Proceedings of the National Academy of... Dec 2014
Topics: Animals; Animals, Wild; Behavior, Animal; Female; Male; Pan troglodytes; Social Behavior
PubMed: 25512536
DOI: 10.1073/pnas.1421559112