靈長類動物是人類的近親,，在進(jìn)化的過程中它們與人類發(fā)生了分歧,，它們的一些行為有時令人難以捉摸。近日,，科學(xué)家找到了雄性卷尾猴(capuchin monkey)為何將尿液涂裹在身上原因,。
研究發(fā)現(xiàn)雄性卷尾猴將尿液涂抹在身上的行為是為了吸引單身的雌性卷尾猴
據(jù)國外媒體報道，研究發(fā)現(xiàn)雄性卷尾猴將尿液涂抹在身上的行為是為了吸引單身的雌性卷尾猴,。據(jù)研究人員介紹,，雄性成年卷尾猴身上的尿液會散發(fā)出男性氣息，能夠引發(fā)雌性卷尾猴的一系列腦部活動,。
早前也有關(guān)于這類的研究,，當(dāng)時科學(xué)家想通過對尿液的檢測而得出結(jié)論，結(jié)果并非得償所愿,。早前科學(xué)家還猜測這種行為能幫助卷尾猴保持體溫或者是能便于猴子間的區(qū)分,。
美國德克薩斯州三一大學(xué)(Trinity University)的心理學(xué)博士金伯利(Kimberley Phillips)教授一直在從事有關(guān)靈長類動物生物學(xué)與神經(jīng)學(xué)基礎(chǔ)行為的研究。他發(fā)現(xiàn)當(dāng)附近有雌性卷尾猴時,，雄性成年卷尾猴會增加身上涂抹的尿液比例,。
于是他進(jìn)行了更深入的研究，金伯利博士使用了磁共振成像技術(shù)來掃描雌性卷尾猴的大腦,。當(dāng)雄性卷尾猴的尿液氣味被雌性"捕捉"到時,，雌性卷尾猴的腦部活動會變得活躍起來。這證實了雄性成年卷尾猴將尿液涂裹身上是為了吸引雌性卷尾猴,。該項研究刊登在了最新的美國靈長類動物學(xué)雜志(Journal of Primatology)上,。
雄性成年卷尾猴的尿液中會摻雜著較高濃度的睪丸激素，以便讓雌性卷尾猴能檢測到它的氣味,。卷尾猴生活在南美洲中部,，猴群內(nèi)的雄性個體多于雌性，一般以雄猴為群體的首領(lǐng),。另外,，睪丸激素濃度影響著雄性成年卷尾猴在猴群的地位，往往濃度越高的雄性地位也就越高,。
金伯利教授表示,，雌性卷尾猴能用大腦區(qū)分出成年雄性卷尾猴和小卷尾猴的尿液，這也許是猴群中異性溝通的一種方式,。（生物谷Bioon.com）
生物谷推薦原文出處：
Am. J. Primatol. 73:1-7, 2011. DOI: 10.1002/ajp.20931
Why do capuchin monkeys urine wash? An experimental test of the sexual communication hypothesis using fMRI
Kimberley A. Phillips1,*, Courtney A. Buzzell2, Nicholas Holder1, Chet C. Sherwood3
Keywords:urine washing;olfactory communication;Cebus
Abstract
Urine washing (UW) consists of depositing urine on the hands and vigorously rubbing the body. As urine contains chemical and pheromonal cues, UW may convey socially relevant information. Although ritualized UW is observed in many New World primates, including capuchin monkeys, the functional significance of UW remains unclear. In this experiment, we investigated the social signaling hypothesis of UW. Specifically, we hypothesized that UW by males conveys socially relevant signals that females can detect. We used functional magnetic resonance imaging (fMRI) to test whether adult female capuchins show differential brain activation in response to adult male and juvenile male capuchin urine. We expected to see changes in activation of structures involved in olfactory processing, including the piriform cortex, medial preoptic and anterior hypothesis, orbitofrontal cortex, hippocampus, and cerebellum. Data were acquired from four adult female capuchin monkeys. Presentations of odor stimuli (obtained from unfamiliar males) were made during fMRI acquisition using a standard ON-OFF design. All fMRI data were spatially normalized to a template and analyzed using the FMRI Expert Analysis Tool Version 5.98, part of the FMRIB's Software Library (www.fmrib.ox.ac.uk/fsl). Whole brain analyses revealed significant activations in the inferior temporal cortex, parahippocampal gyrus, precuneus, hippocampus, pulvinar, and cerebellum when females were presented with the adult male urine. Notably, significantly greater signal activation was observed in several regions associated with olfactory processing, when subjects were presented with adult male urine as compared with urine from juvenile males. Our results indicate that UW serves a social communicative function in capuchins, providing support for the sexual signaling hypothesis.
