Dyble Mark, Thompson James, Smith Daniel, Salali Gul Deniz, Chaudhary Nikhil, Page Abigail E, Vinicuis Lucio, Mace Ruth, Migliano Andrea Bamberg
Anthropology, University College London, London WC1E 6BT, UK.
Anthropology, University College London, London WC1E 6BT, UK.
Curr Biol. 2016 Aug 8;26(15):2017-2021. doi: 10.1016/j.cub.2016.05.064. Epub 2016 Jul 21.
Like many other mammalian and primate societies [1-4], humans are said to live in multilevel social groups, with individuals situated in a series of hierarchically structured sub-groups [5, 6]. Although this multilevel social organization has been described among contemporary hunter-gatherers [5], questions remain as to the benefits that individuals derive from living in such groups. Here, we show that food sharing among two populations of contemporary hunter-gatherers-the Palanan Agta (Philippines) and Mbendjele BaYaka (Republic of Congo)-reveals similar multilevel social structures, with individuals situated in households, within sharing clusters of 3-4 households, within the wider residential camps, which vary in size. We suggest that these groupings serve to facilitate inter-sexual provisioning, kin provisioning, and risk reduction reciprocity, three levels of cooperation argued to be fundamental in human societies [7, 8]. Humans have a suite of derived life history characteristics including a long childhood and short inter-birth intervals that make offspring energetically demanding [9] and have moved to a dietary niche that often involves the exploitation of difficult to acquire foods with highly variable return rates [10-12]. This means that human foragers face both day-to-day and more long-term energetic deficits that conspire to make humans energetically interdependent. We suggest that a multilevel social organization allows individuals access to both the food sharing partners required to buffer themselves against energetic shortfalls and the cooperative partners required for skill-based tasks such as cooperative foraging.
与许多其他哺乳动物和灵长类动物社会一样[1-4]，据说人类生活在多层次的社会群体中，个体处于一系列层次结构分明的子群体中[5,6]。尽管这种多层次的社会组织在当代狩猎采集者中已有描述[5]，但个体从生活在这样的群体中获得的益处仍存在疑问。在这里，我们表明，当代两个狩猎采集者群体——菲律宾的帕拉南阿格塔人和刚果共和国的姆本杰莱巴亚卡人——之间的食物分享揭示了类似的多层次社会结构，个体位于家庭中，在由3至4个家庭组成的分享集群内，在规模各异的更广泛居住营地中。我们认为，这些分组有助于促进两性间的食物供应、亲属间的食物供应以及降低风险的互惠行为，这三种合作层次被认为是人类社会的基本要素[7,8]。人类具有一系列衍生的生活史特征，包括漫长的童年和较短的生育间隔，这使得后代对能量的需求很大[9]，并且已转向一种饮食生态位，这种生态位通常涉及对获取难度大、回报率高度可变的食物的开发利用[10-12]。这意味着人类觅食者面临着日常和更长期的能量不足，这些不足共同导致人类在能量上相互依赖。我们认为，多层次的社会组织使个体既能获得用以缓冲能量短缺所需的食物分享伙伴，又能获得诸如合作觅食等基于技能的任务所需的合作伙伴。
