Masi Shelly, Breuer Thomas
Anthropologie et Ethnobiologie, Centre National de la Recherche Scientifique/Muséum national d'Histoire naturelle, University Paris Diderot, Sorbonne Paris Cité, Musée de l'Homme, Paris, France.
Global Conservation Program, Wildlife Conservation Society, Bronx, New York.
Am J Primatol. 2018 Apr;80(4):e22752. doi: 10.1002/ajp.22752. Epub 2018 Apr 17.
Unraveling the relationship between the unusual feeding behaviors and the nutritional intake of endangered species may provide crucial information for understanding species response to habitat unpredictable changes. Primates occasionally re-ingest fruit seeds alongside ingestion of feces, a behavior called coprophagy. The nutritional benefit is one of the several non-mutual exclusive hypotheses proposed to explain this behavior. We investigated the ecological correlates of coprophagy in wild western gorillas. We tested whether coprophagy occurred during periods of lower fruit availability and whether it led to higher nutrient intake in comparison to the other food. Data integrated phenological, fecal and nutritional analyses of gorilla food with behavioral observations collected at two sites in Central Africa (Mbeli Bai: ad libitum observations on 15 groups/solitary males, October 2002-November 2005; Bai Hokou: 5-min scan on a habituated group, December 2004-December 2005). Coprophagy occurred at the end of the high-fruiting season in association of two Dialium species. Coprophagy correlated positively with the occurrence of Dialium spp. fruit in gorilla feces and in the feeding scans, and showed a positive trend with Dialium availability but not with total fruit availability. Nutritional comparison of Dialium seeds with other important gorilla food showed higher fat and mineral content, particularly of Mg, but also of phenols and tannins in Dialium seeds. We discuss how the effect of gut processing and gut heat via coprophagy may act as cooking-like effect: increasing the ability to maximize nutrient intake by concurrently softening fibers and decreasing the toxic effect of antifeedants, like in human traditional cooking. Our results support both the multiple nutritional benefit hypothesis and the toxicity reduction hypothesis. Since Dialium is precious timber, the importance of this tree for the critically endangered western gorillas should be taken with high consideration when planning controlled logging of degraded forests or in face of habitat changes.
揭示濒危物种异常进食行为与营养摄入之间的关系，可能为理解物种对栖息地不可预测变化的反应提供关键信息。灵长类动物偶尔会在摄入粪便的同时重新摄取果实种子，这种行为被称为食粪行为。营养益处是为解释这种行为而提出的几种并非相互排斥的假设之一。我们调查了野生西部大猩猩食粪行为的生态相关因素。我们测试了食粪行为是否发生在果实可获得性较低的时期，以及与其他食物相比，它是否能带来更高的营养摄入。我们整合了大猩猩食物的物候、粪便和营养分析数据以及在中非两个地点收集的行为观察数据（姆贝利白沙滩：2002年10月至2005年11月对15个群体/独居雄性进行自由观察；白河口：2004年12月至2005年12月对一个习惯化群体进行5分钟扫描）。食粪行为发生在高果季末期，与两种猴面包树属植物有关。食粪行为与大猩猩粪便和进食扫描中猴面包树属果实的出现呈正相关，并且与猴面包树的可获得性呈正趋势，但与总果实可获得性无关。对猴面包树种子与其他重要的大猩猩食物进行营养比较发现，猴面包树种子的脂肪和矿物质含量更高，特别是镁，还有酚类和单宁。我们讨论了通过食粪行为进行肠道处理和肠道加热的效果如何可能起到类似烹饪的作用：通过同时软化纤维和降低抗营养剂的毒性作用，提高最大限度摄入营养的能力，就像人类传统烹饪一样。我们的结果支持了多重营养益处假设和毒性降低假设。由于猴面包树是珍贵木材，在规划对退化森林的控制性采伐或面对栖息地变化时，应高度重视这种树对极度濒危的西部大猩猩的重要性。
