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Humans can use an intuitive sense of statistics to make predictions about uncertain future events, a cognitive skill that underpins logical and mathematical reasoning. Recent research shows that some of these abilities for statistical inferences can emerge in preverbal infants and non-human primates such as apes and capuchins. An important question is therefore whether animals share the full complement of intuitive reasoning abilities demonstrated by humans, as well as what evolutionary contexts promote the emergence of such skills. Here, we examined whether free-ranging rhesus macaques (Macaca mulatta) can use probability information to infer the most likely outcome of a random lottery, in the first test of whether primates can make such inferences in the absence of direct prior experience. We developed a novel expectancy-violation looking time task, adapted from prior studies of infants, in order to assess the monkeys' expectations. In Study 1, we confirmed that monkeys (n = 20) looked similarly at different sampled items if they had no prior knowledge about the population they were drawn from. In Study 2, monkeys (n = 80) saw a dynamic ‘lottery’ machine containing a mix of two types of fruit outcomes, and then saw either the more common fruit (expected trial) or the relatively rare fruit (unexpected trial) fall from the machine. We found that monkeys looked longer when they witnessed the unexpected outcome. In Study 3, we confirmed that this effect depended on the causal relationship between the sample and the population, not visual mismatch: monkeys (n = 80) looked equally at both outcomes if the experimenter pulled the sampled item from her pocket. These results reveal that rhesus monkeys spontaneously use information about probability to reason about likely outcomes, and show how comparative studies of nonhumans can disentangle the evolutionary history of logical reasoning capacities.
Data Types:
  • Other
  • Video
  • Dataset
While the ramifications associated with polybrominated diphenyl ethers (PBDE) exposures during human pregnancy have yet to be determined, increasing evidence in humans and animal models suggests that these compounds cause neurodevelopmental toxicity. Human embryonic stem cell models (hESCs) can be used to study the effects of environmental chemicals on the successive stages of neuronal development. Here, using a hESC differentiation model, we investigated the effects of common PBDE congeners (BDE-47 or -99) on the successive stages of early neuronal development. First, we determined the points of vulnerability to PBDEs across four stages of in vitro neural development by using assays to assess for cytotoxicity. Differentiated neural progenitors were identified to be more sensitive to PBDEs than their less differentiated counterparts. In follow-up investigations, we observed BDE-47 to inhibit functional processes critical for neurogenesis (e.g., proliferation, migration) in hESC-derived neural precursor cells (NPCs) at sub-lethal concentrations. Finally, to determine the mechanism(s) underlying PBDE-toxicity, we conducted global transcriptomic and methylomic analyses of BDE-47. We identified 589 genes to be differentially expressed (DE) due to BDE-47 exposure, including molecules involved in oxidative stress mediation, cell cycle, hormone signaling, steroid metabolism, and neurodevelopmental pathways. In parallel analyses, we identified a significant increase in CpG methylation. In summary, our results suggest, on a cellular level, PBDEs induce human neurodevelopmental toxicity in a concentration-dependent manner and sensitivity to these compounds is dependent on the developmental stage of exposure. Proposed mRNA and methylomic perturbations may underlie toxicity in early embryonic neuronal populations.
Data Types:
  • Video
  • Dataset
Characterising adaptive genetic divergence among conspecific populations is often achieved by studying genetic variation across defined environmental gradients. In marine systems this is challenging due to a paucity of information on habitat heterogeneity at local and regional scales and a dependency on sampling regimes that are typically limited to broad longitudinal and latitudinal environmental gradients. As a result, the spatial scales at which selection processes operate and the environmental factors that contribute to genetic adaptation in marine systems are likely to be unclear. In this study we explore patterns of adaptive genetic structuring in a commercially- harvested abalone species (Haliotis rubra) from south-eastern Australia, using a panel of genome-wide SNP markers (5,239 SNPs), and a sampling regime informed by marine LiDAR bathymetric imagery and 20-year hindcasted oceanographic models. Despite a lack of overall genetic structure across the sampling distribution, significant genotype associations with heterogeneous habitat features were observed at local and regional spatial scales, including associations with wave energy, ocean current, sea surface temperature, and geology. These findings provide insights into the potential resilience of the species to changing marine climates and the role of migration and selection on recruitment processes, with implications for conservation and fisheries management. This study points to the spatial scales at which selection processes operate in marine systems and highlights the benefits of geospatially-informed sampling regimes for overcoming limitations associated with marine population genomic research.
Data Types:
  • Geospatial Data
  • Dataset
1.Prioritising conservation of source populations within landscapes is proposed as a strategy for recovering tigers globally. We studied population dynamics of tigers in Corbett National Park (CNP) in Indian Terai, which harbours the largest and highest density tiger population in any protected area of the world. Through population viability models we demonstrate the importance of CNP in tiger recovery of western Terai. 2.We camera trapped 521 km2 of CNP using open population capture‐mark‐recapture framework between 2010‐2015 to estimate annual abundance, spatially explicit density, survival, recruitment, temporary movements, sex ratio and proportion of females breeding. We model metapopulation persistence with and without Corbett as a source within western Terai landscape at different levels of poaching and habitat connectivity. 3.In six years we recorded 6202 photo‐captures of 307 individual tigers. Annual tiger abundance and density were stable at 120 (SE 19) and 14 (SE 3) per 100 km2 respectively. Overall detection probability of tigers was (0.18 SE 0.03) and detection corrected male: female sex ratio was female biased (0.80 SE 0.13). Apparent annual survival probability was 0.79 (SE 0.05) for females and 0.60 (SE 0.04) for males. Overall survival (0.68 SE 0.12) was lower than that reported for other tiger populations. CNP tigers showed high reproduction with 54.8 (SE 5.1) % females breeding and with addition of 35(SE 8)% as new recruits to the population each year. Small tiger populations in the western Terai with moderate poaching could only persist through dispersal from CNP. 4.Synthesis and applications: The Corbett tiger population was characterised by a stable high density, high reproductive rate and low survival resulting in high turnover rates of 32‐48% between successive years. Such source populations could sustain low level poaching and with habitat connectivity recover tiger populations across the landscape. This study establishes potential thresholds that can likely be achieved by tiger populations under optimal natural conditions and highlights the importance of prioritizing conservation of source populations within tiger landscapes. This information can be used to plan and implement realistic tiger recovery programmes globally.
Data Types:
  • Geospatial Data
  • Dataset
The Near East cattle are adapted to different agro-ecological zones including desert areas, mountains habitats as well as humid regions along the Tigris and Euphrates rivers system. The region was one of the earliest and most significant areas of cattle husbandry. Currently four main breeds of Iraqi cattle are recognized. Among these, the Jenoubi is found in the southern more humid part of Iraq while the Rustaqi is found in the middle and drier region of the country. Despite their importance, Iraqi cattle have up to now been poorly characterized at genome level. Here, we report at genome-wide level the diversity and signature of positive selection in these two breeds. Thirty-five unrelated Jenoubi cattle, sampled in the Maysan and Basra regions, and 60 Rustaqi cattle, from around Baghdad and Babylon, were genotyped using the Illumina Bovine HD BeadChip (700K). Genetic population structure and diversity level were studied using principal component analysis (PCA), expected heterozygosity (He), observed heterozygosity (Ho) and admixture. Signatures of selection were studied using Extended Haplotype Homozygosity (EHH) (iHS and Rsb) and inter-population Wright’s Fst. The results of PCA and admixture analysis, including European taurine, Asian indicine, African indicine and taurine indicate that the two breeds are crossbreed zebu x taurine, with more zebu background in Jenoubi cattle compared to Rustaqi. The Rustaqi has the greatest mean heterozygosity (He = 0.37) among all breeds. iHS and Rsb signature of selection analyses identify 68 candidate genes under positive selection in the two Iraqi breeds, while Fst analysis identifies 220 candidate genes including genes related to the innate and acquired immunity responses, different environmental selection pressures (e.g. tick resistance, heat stress) and genes of commercial interest (e.g. marbling score).
Data Types:
  • Geospatial Data
  • Sequencing Data
  • Dataset
Objectives: The emergence of human-unique cognitive abilities has been linked to our species' extended juvenile period. Comparisons of cognitive development across species can provide new insights into the evolutionary mechanisms shaping cognition. This study examined the development of different components of spatial memory, cognitive mechanisms that support complex foraging, by comparing two species with similar life history that vary in wild ecology: bonobos (Pan paniscus) and chimpanzees (Pan troglodytes). Materials and methods: Spatial memory development was assessed using a cross-sectional experimental design comparing apes ranging from infancy to adulthood. Study 1 tested 73 sanctuary-living apes on a task examining recall of a single location after a 1-week delay, compared to an earlier session. Study 2 tested their ability to recall multiple locations within a complex environment. Study 3 examined a subset of individuals from Study 2 on a motivational control task. Results: In Study 1, younger bonobos and chimpanzees of all ages exhibited improved performance in the test session compared to their initial learning experience. Older bonobos, in contrast, did not exhibit a memory boost in performance after the delay. In Study 2, older chimpanzees exhibited an improved ability to recall multiple locations, whereas bonobos did not exhibit any age-related differences. In Study 3, both species were similarly motivated to search for food in the absence of memory demands. Discussion: These results indicate that closely related species with similar life history characteristics can exhibit divergent patterns of cognitive development, and suggests a role of socioecological niche in shaping patterns of cognition in Pan.
Data Types:
  • Other
  • Video
  • Dataset
Purpose: Surgical education videos currently all use a single point of view (POV) with the trainee locked onto a fixed viewpoint, which may not deliver sufficient information for complex procedures. We developed a novel multiple POV video system and evaluated its training outcome compared with traditional single POV. Methods: We filmed a hip resurfacing procedure performed by an expert attending using 8 cameras in theatre. 30 medical students were randomly and equally allocated to learn the procedure using the multiple POV (experiment group [EG]) versus single POV system (control group [CG]). Participants advanced a pin into the femoral head as demonstrated in the video. We measured the drilling trajectories and compared it with pre-operative plan to evaluate distance of the pin insertion and angular deviations. Two orthopedic attendings expertly evaluated the participants' performance using a modified global rating scale (GRS). There was a pre-video knowledge test that was repeated post-simulation alongside a Likert-scale questionnaire. Results: The angular deviation of the pin in EG was significantly less by 29% compared to CG (p=0.037), with no significant difference in the entry point's distance between groups (p=0.204). The GRS scores for EG were higher than CG (p=0.046). There was a 32% higher overall knowledge test score (p<0.001) and 21% improved Likert-scale questionnaire score (p=0.002) after video-learning in EG than CG, albeit no significant difference in the knowledge test score before video-learning (p=0.721). Conclusion: The novel multiple POV provided significant objective and subjective advantages over single POV for acquisition of technical skills in hip surgery.
Data Types:
  • Other
  • Video
  • Dataset
The honey bee (Apis mellifera L.) is an important pollinator and a model for pesticide effects on insect pollinators. The effects of agricultural pesticides on honey bee health have therefore raised concern. Bees can be exposed to multiple pesticides that may interact synergistically, amplifying their side-effects. Attention has focused on neonicotinoid pesticides, but flupyradifurone (FPF) is a novel butenolide insecticide that is also systemic and a nicotinic acetylcholine receptor (nAChR) agonist. We therefore tested the lethal and sublethal toxic effects of FPF over different seasons and worker types, and the interaction of FPF with a common SBI fungicide, propiconazole. We provide the first demonstration of adverse synergistic effects on bee survival and behaviour (poor coordination, hyperactivity, apathy) at field-realistic doses. Pesticide effects were significantly influenced by worker type and season. Foragers were consistently more susceptible to these pesticides (4-fold greater effect) than in-hive bees, and both worker types were more strongly affected by FPF in summer as compared to spring. Because risk assessment requires relatively limited tests that only marginally address bee behaviour and do not consider the influence of bee age and season, our results raise concerns about the safety of approved pesticides, including FPF. We suggest that pesticide risk assessment also test for common chemical mixture synergies on behaviour and survival.
Data Types:
  • Other
  • Video
  • Tabular Data
  • Dataset
Color is among the most striking features of organisms, varying not only in spectral properties like hue and brightness, but also in where and how it is produced on the body. Different combinations of colors on a bird’s body are important in both environmental and social contexts. Previous comparative studies have treated plumage patches individually or derived plumage complexity scores from color measurements across a bird’s body. However, these approaches do not consider the multivariate nature of plumages (allowing for plumage to evolve as a whole) or account for interpatch distances. Here, we leverage a rich toolkit used in historical biogeography to assess color pattern evolution in a cosmopolitan radiation of birds, kingfishers (Aves: Alcedinidae). We demonstrate the utility of this approach and test hypotheses about the tempo and mode of color evolution in kingfishers. Our results highlight the importance of considering interpatch distances in understanding macroevolutionary trends in color diversity and demonstrate how historical biogeography models are a useful way to model plumage color pattern evolution. Furthermore, they show that distinct color mechanisms (pigments or structural colors) spread across the body in different ways and at different rates. Specifically, net rates are higher for structural colors than pigment-based colors. Together, our study suggests a role for both development and selection in driving extraordinary color pattern diversity in kingfishers. We anticipate this approach will be useful for modeling other complex phenotypes besides color, such as parasite evolution across the body.
Data Types:
  • Software/Code
  • Video
  • Tabular Data
  • Dataset
  • Document
  • Text
  • File Set
Horse locomotion is remarkably economical. Here we measure external mechanical work of the galloping horse and relate it to published measurements of metabolic cost. Seven Thoroughbred horses were galloped (ridden) over force plates, under a racing surface. Twenty-six full strides of force data were recorded and used to calculate external mechanical work of galloping. The mean sum of decrements of mechanical energy was -876J (± 280J) per stride and increments were 2163J (± 358J) per stride as horses were accelerating. Combination with published values for internal work and metabolic costs for galloping yield an apparent muscular efficiency of 37-46% for galloping which would be reduced by energy storage in leg tendons. Knowledge about external work of galloping provides further insight into the mechanics of galloping from both an evolutionary and performance standpoint.
Data Types:
  • Video
  • Tabular Data
  • Dataset
  • Document
  • Text
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