Human and nonhuman primates show a preference for looking at faces with direct gaze. In humans, this preference emerges shortly after birth, but little is known about the development of gaze preferences in monkeys. This study tracked the development of gaze preferences in infant monkeys from birth through 6 months of age using infrared eye-tracking. Although absent in the first week, a strong significant preference for direct compared to averted gaze faces emerged rapidly, peaking around 2 months of age. When looking at the eyes, the monkeys' fixations were equivalent in duration for both gaze types in the first 2 months, but thereafter remained longer for the averted gaze faces. Therefore, the infants spent a greater proportion of time overall, but made shorter fixations, when looking at the direct compared to averted gaze faces. These results suggest that monkeys develop an efficient strategy when viewing the preferred direct gaze faces that involves longer viewing times, but shorter fixations.

The way that people manage their livestock tells us about their interactions with the landscape, particularly the nature of adaptation to specific environments, social organisation, resilience and long-term farming sustainability. Globally, there is considerable variation in how these practices are manifested, due to differences in water availability, levels of environmental diversity and aridity, and also the nature of cultural choices. South Asia's Indus Civilisation (c.3000-1500 BCE) provides an important opportunity for investigating how populations managed their animals, because the region shows considerable diversity in rainfall distribution, seasonality and intensity, which results in marked environmental variability that is susceptible to change over time. The latter is particularly significant when it comes to consideration of the impact of the 4.2 ka BP event and its relation to the deurbanisation of the Indus Civilisation.This paper presents carbon isotope data from animal teeth from nine archaeological sites distributed across northwest India that are suitable for exploring how diverse practices were, and how animal management strategies changed through time. These data show clear differentiation in feeding practices between species, with cattle and water buffalo consuming very high proportions of C 4 plants, while sheep and goat ate varying quantities of C 3 and C 4 plants. This pattern is generally consistent across sites and throughout different periods, suggesting that the strategy was adapted to a range of environmental conditions and settlements of different sizes. We suggest that humans controlled cow and water buffalo diets, and they were likely provided with fodder. In contrast, sheep and goats had a less controlled diet, and were presumably more likely to roam the landscape. These animal management strategies must have involved some separation of tasks, although it remains unclear if this was on a household, settlement or population level.

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Greetings in primates fulfil important functions including navigation of rank, maintenance of social relationships, and potentially establishing coalition partnerships. Papio makes a particularly valuable study genus as baboons show variation in greeting, male-male cooperation, philopatry, and social system. However, baboon greeting research has largely focused on male-male interactions, with female approach behaviour neglected except in relation to friendships and grunting. Most if not all signals seen in male-male greetings are also present in approaches between other sex combinations. To understand these signals further, their use in all sex combinations should be explored. We investigated approaches between male and female adult chacma baboons (Papio ursinus griseipes, the only savannah baboon reportedly lacking male-male cooperation, recorded in Gorongosa National Park, Mozambique. We compared male-male greetings with those of other baboon species, identified network clusters of co-occurring signals, and compared male and female approaches more broadly. Male-male approaches were similar to those in other baboon species. We identified several predictable signal combinations, ear-flattening with lip-smacking being a particularly strong signal of benign intent across sexes. Further research comparing greeting across sex combinations and species will help disentangle links between risk, cooperation, and greeting behaviour.