最新研究顯示,，與有時無法抗拒漢堡包誘惑的素食者一樣,，本是食草動物的大猩猩可能在一定條件下，也禁不住誘惑將魔爪伸向同類,。
盡管有些動物園飼養(yǎng)的大猩猩會吃肉,，但就科學家所知，野生大猩猩僅以植物,、水果以及奇異的昆蟲為食,。然而，最新一項研究在加蓬盧安果國家公園的非洲野生山地大猩猩的糞便中發(fā)現了猴和小羚羊的DNA樣本,。這一發(fā)現提出了一種可能性,，即野生大猩猩可能具有秘密的食肉習慣——以腐肉為食。
德國馬克斯-普朗克協(xié)會進化人類學研究所靈長類行為學家格利特-舒伯特(Grit Schubert)參與實施了這項研究,。他認為,，這項驚人發(fā)現或許具有更為平常的解釋——而在黑猩猩可能被列為食肉動物之前，這些解釋必須一一被排除掉。例如,，大猩猩吃螞蟻,，而螞蟻又以猴和其他哺乳動物的尸體和骨骼為食。研究人員推測,，當大猩猩吃掉螞蟻的時候,，它們可能還吞下存在于螞蟻消化道中的哺乳動物DNA，然后再排出體外,。
另一種可能性則是,，哺乳動物DNA來自于活猴或小羚羊，它們在大猩猩糞便中尋找可以食用的種子或其他殘留植物顆粒時留下了自己的DNA,。舒伯特說,，猴或小羚羊“可能舔了舔大猩猩的糞便，或是聞了聞,，或是在上面撒尿,。大猩猩的糞便中出現哺乳動物DNA的可能性有很多。我并不認為大猩猩會吃肉,。”
如果大猩猩真的吃肉,，那么它們可能就是第一種食肉類人猿。我們知道,，黑猩猩和倭黑猩猩就捕食其他哺乳動物,，比如猴。馬克斯-普朗克協(xié)會的遺傳學家邁克爾-霍夫利特(Michael Hofrieter)也參與了這項研究,。他說：“大多數食草動物都善于消化肉類,。”研究結果于2月25日發(fā)表在《公共科學圖書館-綜合》雜志的網站上。（生物谷Bioon.com）
猩猩吞食自己排泄物
生物谷推薦原始出處：
PLoS ONE 5(2): e9419. doi:10.1371/journal.pone.0009419
Vertebrate DNA in Fecal Samples from Bonobos and Gorillas: Evidence for Meat Consumption or Artefact?
Michael Hofreiter1,2*, Eva Kreuz1, Jonas Eriksson3,4, Grit Schubert3, Gottfried Hohmann3
1 Research Group Molecular Ecology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, 2 Department of Biology, University of York, York, United Kingdom, 3 Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, 4 Animal Ecology, Evolutionary Biology Centre (EBC), Uppsala University, Uppsala, Sweden
Background
Deciphering the behavioral repertoire of great apes is a challenge for several reasons. First, due to their elusive behavior in dense forest environments, great ape populations are often difficult to observe. Second, members of the genus Pan are known to display a great variety in their behavioral repertoire; thus, observations from one population are not necessarily representative for other populations. For example, bonobos (Pan paniscus) are generally believed to consume almost no vertebrate prey. However, recent observations show that at least some bonobo populations may consume vertebrate prey more commonly than previously believed. We investigated the extent of their meat consumption using PCR amplification of vertebrate mitochondrial DNA (mtDNA) segments from DNA extracted from bonobo feces. As a control we also attempted PCR amplifications from gorilla feces, a species assumed to be strictly herbivorous.
Principal Findings
We found evidence for consumption of a variety of mammalian species in about 16% of the samples investigated. Moreover, 40% of the positive DNA amplifications originated from arboreal monkeys. However, we also found duiker and monkey mtDNA in the gorilla feces, albeit in somewhat lower percentages. Notably, the DNA sequences isolated from the two ape species fit best to the species living in the respective regions. This result suggests that the sequences are of regional origin and do not represent laboratory contaminants.
Conclusions
Our results allow at least three possible and mutually not exclusive conclusions. First, all results may represent contamination of the feces by vertebrate DNA from the local environment. Thus, studies investigating a species' diet from feces DNA may be unreliable due to the low copy number of DNA originating from diet items. Second, there is some inherent difference between the bonobo and gorilla feces, with only the later ones being contaminated. Third, similar to bonobos, for which the consumption of monkeys has only recently been documented, the gorilla population investigated (for which very little observational data are as yet available) may occasionally consume small vertebrates. Although the last explanation is speculative, it should not be discarded a-priori given that observational studies continue to unravel new behaviors in great ape species.
