34 results match your criteria: "Kyoto University Primate Research Institute[Affiliation]"

Article Synopsis
  • Maternal behavior in primates shows significant variation and influences the behaviors of their immature offspring, but the extent of this impact is still not fully understood.
  • In a study of Japanese macaques, researchers found that juveniles with mothers who frequently rejected them were more likely to engage with peers, even when mothers were absent, indicating a lasting effect of maternal rejection.
  • Conversely, juveniles with more protective mothers tended to play less and interact less with others, but this influence seemed to diminish when the mother was not nearby, suggesting different dynamics between maternal rejection and protectiveness.
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  • Environmental contamination, particularly in wetlands, significantly contributes to biodiversity loss, impacting species during critical development phases.
  • This study examined the effects of the herbicide nicosulfuron on spined toad tadpoles at various developmental stages, revealing that exposure led to larger size but altered body and tail muscle traits, increased activity, and changes in swimming speed and behavior.
  • Results indicated that higher concentrations of the herbicide correlated with more significant effects, and that the timing of exposure did not change the outcomes, highlighting the importance for regulators to address sublethal concentrations in environmental policies.
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We performed a comprehensive fecal metabolite analysis using LC-MS/MS and LC-QTOF-MS approaches as a preliminary study. Feces of Japanese macaques on Yakushima Island were collected from five monkeys at two separate locations. Using the former methodology, 59 substances such as free amino acids, nucleotides, nucleosides and nucleic acid bases, and organic acids in the citrate cycle were quantitatively detected and successfully differentiated in two different monkey groups by the concentrations of nucleic acid metabolites and free amino acids.

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Why aren't rabbits and hares larger?

Evolution

April 2021

Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA.

Macroevolutionary consequences of competition among large clades have long been sought in patterns of lineage diversification. However, mechanistically clear examples of such effects remain elusive. Here, we postulated that the limited phenotypic diversity and insular gigantism in lagomorphs could be explained at least in part by an evolutionary constraint placed on them by potentially competing ungulate-type herbivores (UTHs).

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  • Changes in marine ecosystems are more easily observed in predators like seabirds since they connect different levels of the food web.
  • A study on little penguins reveals that their diving behavior is affected by sea surface temperature and water stratification, impacting how efficiently they forage for food.
  • Penguins foraging in warmer, stratified waters displayed more complex diving patterns and higher foraging efficiency, indicating they adapt their strategies based on environmental conditions.
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Biometric ratios of the relative length of the rays in the hand have been analyzed between primate species in the light of their hand function or phylogeny. However, how relative lengths among phalanges are mechanically linked to the grasping function of primates with different locomotor behaviors remains unclear. To clarify this, we calculated cross and triple-ratios, which are related to the torque distribution, and the torque generation mode at different joint angles using the lengths of the phalanges and metacarpal bones in 52 primates belonging to 25 species.

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  • Group-living animals experience social interactions shaped by socioecological factors, affecting both individual behaviors and the overall social network structure.
  • These factors impact animal health and reproductive success by influencing stress levels, information sharing, and mating systems, thereby altering social behaviors and the topology of social networks.
  • The paper emphasizes the role of evolutionary forces in shaping social strategies and network structures, highlighting the adaptability of networks to changing conditions, which reflects a process called "network evolution" and the concept of "collective social niche construction."
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Behaviour of nonhuman primate mothers toward their dead infants: uncovering mechanisms.

Philos Trans R Soc Lond B Biol Sci

September 2018

Center for International Collaboration and Advanced Studies in Primatology (CICASP) & Section of Language and Intelligence, Kyoto University Primate Research Institute, 41-2 Kanrin, Inuyama, Aichi 484-8506, Japan.

In comparative thanatology, most reports for nonhuman mammals concern mothers' behavioural responses to their dead offspring: most prominently, dead-infant carrying (sometimes of extended duration); but also inspection, proximity, maternal care such as grooming, protective behaviours and filial cannibalism. Documented across many primate species, these behaviours remain poorly understood in all. The literature is dominated by relatively brief qualitative descriptions of isolated anecdotal cases in apes and monkeys.

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The Southern Ocean is currently experiencing major environmental changes, including in sea-ice cover. Such changes strongly influence ecosystem structure and functioning and affect the survival and reproduction of predators such as seabirds. These effects are likely mediated by reduced availability of food resources.

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Article Synopsis
  • The study explores various hypotheses that explain self-directed behaviors like scratching and self-grooming in female Japanese macaques, including parasite load, environmental conditions, and social factors.
  • Researchers conducted observations and used statistical models to investigate the impact of lice load, social dynamics, and environmental factors on these behaviors.
  • Results indicated a strong connection between scratching and ectoparasite load, while self-grooming was influenced by social grooming, dominance rank, and social interactions, suggesting a complex interplay between biological and social factors.
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Article Synopsis
  • Social structures can impact disease risk by influencing how close individuals are and how often they interact, which is particularly relevant for primates with complex social networks.
  • A study on Japanese macaques used social network analysis to identify how relationships within the group affect the transmission of a theoretical infectious agent, finding that more central individuals transmit infections faster and get infected sooner.
  • However, the research showed that in some cases, the spread of disease in these macaque networks did not significantly differ from random networks, suggesting that individual characteristics may not always play a crucial role in disease transmission.
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  • - Lice, which are ectoparasites, are transmitted socially among female Japanese macaques, and their spread is influenced by the macaques' contact with each other during grooming.
  • - A study tested two predictions about the relationship between social grooming and lice load: one suggesting central females would have more lice due to their contacts, and another suggesting they would have fewer due to increased grooming.
  • - Results showed that more social interactions correlated with lower lice loads in winter and summer, contradicting the idea that more contact means more lice, and highlighting how grooming can reduce lice burden, influenced by seasonal variations and the biology of both the parasites and macaques.
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Despite being a charismatic and well-known species, the social system of the koala (Phascolarctos cinereus--the only extant member of the family Phascolarctidae) is poorly known and much of the koala's sociality and mating behaviors remain un-quantified. We evaluated these using proximity logging-GPS enabled tracking collars on wild koalas and discuss their implications for the mating system of this species. The frequency and duration of male-female encounters increased during the breeding season, with male-male encounters quite uncommon, suggesting little direct mating competition.

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Chimpanzee choice rates in competitive games match equilibrium game theory predictions.

Sci Rep

June 2014

1] Division of the Humanities and Social Sciences, Caltech, Pasadena CA 91125, USA [2] Computation & Neural Systems, Caltech.

The capacity for strategic thinking about the payoff-relevant actions of conspecifics is not well understood across species. We use game theory to make predictions about choices and temporal dynamics in three abstract competitive situations with chimpanzee participants. Frequencies of chimpanzee choices are extremely close to equilibrium (accurate-guessing) predictions, and shift as payoffs change, just as equilibrium theory predicts.

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Article Synopsis
  • From the late 1960s to early 1970s, a significant number of congenitally malformed Japanese macaque infants were observed, with a notable decrease in occurrences later on.
  • The suspected main cause of the malformations is agrichemicals present in the provisioned food, as other factors like population size and birth rate showed no influence.
  • The study revealed higher rates of malformations in males, particularly in feet and specifically in the fourth digit, correlating with the increased provision of food during that period.
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Animal behaviour exhibits fractal structure in space and time. Fractal properties in animal space-use have been explored extensively under the Lévy flight foraging hypothesis, but studies of behaviour change itself through time are rarer, have typically used shorter sequences generated in the laboratory, and generally lack critical assessment of their results. We thus performed an in-depth analysis of fractal time in binary dive sequences collected via bio-logging from free-ranging little penguins (Eudyptula minor) across full-day foraging trips (2(16) data points; 4 orders of temporal magnitude).

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Parasitism and other stressors are ubiquitous in nature but their effects on animal behaviour can be difficult to identify. We investigated the effects of nematode parasitism and other indicators of physiological impairment on the sequential complexity of foraging and locomotion behaviour among wild Japanese macaques (Macaca fuscata yakui). We observed all sexually mature individuals (n = 28) in one macaque study group between October 2007 and August 2008, and collected two faecal samples/month/individual (n = 362) for parasitological examination.

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Parasites are characteristically aggregated within hosts, but identifying the mechanisms underlying such aggregation can be difficult in wildlife populations. We examined the influence of host age and sex over an annual cycle on the eggs per gram of feces (EPG) of nematode parasites infecting wild Japanese macaques (Macaca fuscata yakui) on Yakushima Island. Five species of nematode were recorded from 434 fecal samples collected from an age-structured group of 50 individually recognizable macaques.

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The objective of this study was to test the hypothesis that activity-behavioral sleep parameters differ between nocturnallyactive owl monkeys and diurnally-active squirrel monkeys which are sympatric and of Bolivian origin. The total sleep time (TST) and sleep episode length (SEL) of 7 adult owl monkey siblings and 4 adult squirrel monkeys were quantitated by actigraphy for 7 days under captive conditions. The higher TST/24 h values and longer SEL/12 h quiescent phase quantitated for owl monkeys in comparison to that of squirrel monkeys clearly indicate that the behavioral sleep is markedly different between these two groups, though they are sympatric in wild.

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Vigilance is thought to have evolved as an antipredator defense but, in primates, conspecific threat often better explains this behavior. We examined vigilance in one group of Colobus vellerosus inhabiting the Boabeng-Fiema Monkey Sanctuary in Ghana. We aimed to (1) describe factors affecting vigilance in this population, and (2) examine the importance of predation avoidance and conspecific threat in explaining vigilance patterns.

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Data on the development of the perception of facial biological motion during preschool years are disproportionately scarce. We investigated the ability of preschoolers to recognise happy, angry, and surprised expressions, and eye-closing facial movements on the basis of facial biological motion. Children aged 4 years (n = 18) and 5-6 years (n = 19), and adults (n = 17) participated in a matching task, in which they were required to match the point-light displays of facial expressions to prototypic schematic images of facial expressions and facial movement.

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Background: A table summarizing the primary literature on 19 species of longevous non-human primates, other than owl monkey, is presented.

Methods: We prospectively quantitated the sleep of a longevous female owl monkey (Aotus azarae), aged >30 years, longitudinally for 2 years and also evaluated the senility-induced change in spinal curvature.

Results: The mean daily total sleep time (TST) of this monkey ranged between 790 and 1106 minutes, and was markedly higher in comparison with its female progeny (aged 16 years and used as a control) whose daily TST during the same experimental period ranged between 612 and 822 minutes.

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Sleep quantitation in common marmoset, cotton top tamarin and squirrel monkey by non-invasive actigraphy.

Comp Biochem Physiol A Mol Integr Physiol

June 2006

Center for Human Evolution Modeling Research, Kyoto University-Primate Research Institute, Inuyama City 484-8506, Japan.

Sleep quantitation data on the Neotropical primate species, apart from the squirrel monkey, are still sparse. As such, we have quantitated sleep in the common marmosets (Callithrix jacchus), cotton top tamarins (Saguinus oedipus) and squirrel monkeys (Saimiri sciureus) reared in one primate facility simultaneously, by non-invasive actigraphy. The range in total sleep time/24h measured for male adult common marmosets, cotton top tamarins and squirrel monkeys were 713-793 min (n=4), 707-889 min (n=4) and 459-475 min (n=2) respectively.

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