Table_1_Eating smart: Free-ranging dogs follow an optimal foraging strategy while scavenging in groups.pdf

Foraging and acquiring of food is a delicate balance between managing the costs (both energy and social) and individual preferences. Previous research on solitarily foraging free-ranging dogs showed that they prioritise the nutritionally highest valued food, but do not ignore other less valuable food either, displaying typical scavenger behaviour. We conducted a similar experiment on 136 groups of dogs with the same set-up to see the change in foraging strategies, if any, under the influence of social cost like intra-group competition. We found multiple differences between the strategies of dogs foraging alone versus in groups with competition playing an implicit role in the dogs’ decision making when foraging in groups. Dogs continually assessed and evaluated the available resources in a “patch,” transitioning from random foraging to systematic foraging with time and more information. Dogs in groups used an, “eat first, sample afterwards” strategy whereas individual dogs sampled thoroughly before eating. Additionally, dogs in groups were quicker and more likely to respond to the experimental set-up and eat from it. The dogs adjusted their behaviour in terms of effort and time allocated according to the quality of the “patch.” Foraging in groups also provided benefits of reduced individual vigilance. The various decisions and choices made lend support to the optimal foraging theory wherein the dogs harvested the nutritionally richest patch possible with the least risk and cost involved but were willing to compromise if that was not possible. This underscores the cognitive, quick decision-making abilities and adaptable behaviour of these dogs, which is likely to have influenced the process of dog domestication.

觅食与获取食物是一项精妙的平衡行为，需要权衡各项成本（包括能量消耗与社交成本）与个体偏好。过往针对独居觅食的散养犬的研究表明，它们会优先选择营养价值最高的食物，但也不会忽略其他营养价值较低的食物，展现出典型的食腐行为模式。本研究采用相同的实验设置，对136组犬只开展了同类实验，以探究在群体内部竞争等社交成本的影响下，犬的觅食策略是否会发生变化。研究发现，独居觅食与群体觅食的策略存在多处差异，群体觅食时，竞争会对犬的决策产生隐性影响。犬只会持续评估并梳理“觅食斑块（patch）”内的可用资源，随着时间推移与信息积累，会从随机觅食转向系统性觅食。群体觅食的犬只会采用“先进食、后采样”的策略，而独居觅食的犬则会在进食前进行充分采样。此外，群体中的犬对实验装置的响应速度更快，也更愿意取食装置内的食物。犬只会根据“觅食斑块”的质量，调整其所投入的精力与分配的时间。群体觅食还能带来降低个体警戒成本的益处。犬的各类决策与选择均支持最优觅食理论：它们会在风险与成本最低的前提下，尽可能获取营养价值最高的觅食斑块，若无法实现则会选择妥协。这一结果凸显了此类犬的认知能力、快速决策能力与适应性行为，而这些特质很可能对犬的驯化进程产生了影响。