Psychology · Social Psychology
Carrion crows were trained to respond to visual cues with either a vocalization or a peck. Vocal responses were slower and more variable, and switching into them caused additional delays and occasional errors that were largely absent for pecking.
A study of bonobos estimates that moving on two legs could fit into a varied movement repertoire without creating an immediate energy constraint. The findings suggest early human ancestors may have incorporated bipedalism before it became highly efficient.
A three-year study of 103 female rhesus macaques found that those more interested in unfamiliar female faces were more likely to reproduce the next year. Nursing females, however, showed less interest in unfamiliar monkeys than pregnant or nonbreeding females.
Researchers developed an explainable AI system that classified the sex of wild mountain gazelles from camera-trap images. It achieved 75% accuracy and an F1 score of 75%, while highlighting body shape, legs, heads and male horns as important visual cues.
Fossil collections from Lebanon reveal that productive Mediterranean woodlands persisted along the central Levantine coast for much of the period from about 400,000 to 100,000 years ago. The findings also suggest that ancient hominins hunted seasonally in different coastal habitats.
Researchers identified three Denisovan bone fragments and two teeth from Bianfu Cave in Southwest China. The remains, dated to about 167,000–134,000 years ago, add evidence from a region missing from the known Denisovan record.
Among wild Guinea baboons, variation in maternal caregiving style was not linked to infant growth or survival. The researchers suggest that disease and predators may have stronger effects in this population, but future work is needed to examine how infant behaviour and maternal responses interact.
Wild chimpanzees with overlapping visual gestures appeared to share repertoires for reasons beyond repeated exposure and reinforcement. The findings are more consistent with the idea that cues such as vocalizations, gestures and waiting for a response help chimpanzees infer communicative goals in uncertain social situations.
Alpine marmots played less as temperatures rose, while grooming, greetings and aggressive interactions remained comparatively stable. The researchers suggest that declining play could be an early sign of heat stress, although its long-term effects were not measured.
