Understanding the behavior of non-human primates is crucial for improving animal welfare, modeling social behavior, and gaining insights into distinctively human and phylogenetically shared behaviors. However, the lack of datasets on non-human primate behavior hinders in-depth exploration of primate social interactions, posing challenges to research on our closest living relatives. To address these limitations, we present ChimpACT, a comprehensive dataset for quantifying the longitudinal behavior and social relations of chimpanzees within a social group. Spanning from 2015 to 2018, ChimpACT features videos of a group of over 20 chimpanzees residing at the Leipzig Zoo, Germany, with a particular focus on documenting the developmental trajectory of one young male, Azibo. ChimpACT is both comprehensive and challenging, consisting of 163 videos with a cumulative 160,500 frames, each richly annotated with detection, identification, pose estimation, and fine-grained spatiotemporal behavior labels. We benchmark representative methods of three tracks on ChimpACT: (i) tracking and identification, (ii) pose estimation, and (iii) spatiotemporal action detection of the chimpanzees. Our experiments reveal that ChimpACT offers ample opportunities for both devising new methods and adapting existing ones to solve fundamental computer vision tasks applied to chimpanzee groups, such as detection, pose estimation, and behavior analysis, ultimately deepening our comprehension of communication and sociality in non-human primates.

How does group membership framing affect the feedback students provide learners? This paper presents two between-subjects experiments investigating the effect of Ingroup/Outgroup membership on effort spent in peer evaluations, and whether the group membership criterion type affects quality and stringency of evaluation. Two peer-review assignments were implemented in two separate classes. In the first study, students were nominally grouped by location they sat in class and non-nominally grouped by current class score; each was asked to review an Ingroup and Outgroup peer assignment. A second study randomly assigned students to one of four group types (random, score, motivation, and location); student reviewed two Ingroup assignments. In both studies, score-grouped students graded their peers more stringently than students grouped by location. These studies illustrate for system designers the impacts of group framing - and the disclosure of that-in peer review tasks.