Faces and Bodies

Sometimes some interesting stuff escapes your attention. Only recently I read about the work by Frans de Waal and Jennifer Pokorny which won an Ig Nobel Prize in 2012 for “discovering that chimpanzees can identify other chimpanzees individually by seeing photographs of their anogenital regions (their behinds)” [1,2]. Chimpanzees “were not only seeing the photographs as representations of chimps they knew, but linked the face and behind by drawing upon a mental representation of the whole body of those chimps” [3,4].

When I pushed a vision of respectable scientists, taking photos of chimps’ behinds in order to share them with other chimps, away from my imagination, I came to understanding that this discovery might hold a key to understanding the purpose of clothing. Among the Hominidae, chimpanzees are the closest living relatives to humans [5]. Someone even calls humans the “third chimpanzee” [6]. Though, one may ask, “What about humans?”

A psychological study done at the University of Texas in 2013 revealed that “people do better at facial recognition when the whole person, not just the face, is presented”. It appears that “when faces are partially obscured or difficult to differentiate, subtle body cues allow people to identify others with surprising accuracy”. “Our work shows that the body can be surprisingly useful for identification, especially when the face fails to provide the necessary identity information,” project supervisor said [7].

It should be taken into account that in the time-scale of evolution clothing is “a relatively new invention”. “Earliest recorded signs of clothing date to 36,000 BCE”. Considering that the use of clothing has a relatively short history, two scientists have assumed that it is possible “that the responses of the brain networks specialized in body perception could show attenuated responses towards bodies wearing clothing” [8]. It indeed turned out that “the human brain showed enhanced visual processing of nude over clothed bodies”. Human visual system has been found to be particularly sensitive to detecting nude bodies. The experimenters discovered that “brain mechanisms specifically devoted to processing visual information” worked more effectively as the amount of clothing on images shown to healthy male and female volunteers decreased from full clothing via swimsuits to nude bodies. The response traditionally assumed to be most pronounced to human faces proved to be even greater to nude bodies than to faces [8].

With all these in mind, we can now suppose that one of the purposes of clothing is to hide one’s true identity and “fool other’s into believing that he or she has is actually someone else”. In culture, the putting on masks attempting to hide one’s true identity is often considered as suspect or even criminal (see, for instance, [9]). Of course, under certain circumstances, there might be reasons to disguise one’s identity [10]. But, despite the fact that you may “enjoy being someone different”, it’s nice to know you’re still yourself at the end of the day [11].

References

[1] Frans B. M. de Waal, Jennifer J. Pokorny, Faces and Behinds: Chimpanzee Sex Perception, Advanced Science Letters, Volume 1, Number 1, June 2008, pp. 99-103(5)

[2] List of Ig Nobel Prize winners – From Wikipedia, the free encyclopedia

[3] Chimps can recognise friends by their behinds – New Scientist

[4] Butts, Faces Help Chimps Identify Friends – National Geographic News

[5] Chimpanzee – From Wikipedia, the free encyclopedia

[6] Jared M. Diamond, The Third Chimpanzee: The Evolution and Future of the Human Animal, Harper Perennial, 2006

[7] Study: People use body cues to help identify faces

[8] J.K. Hietanen, L. Nummenmaa, The naked truth: the face and body sensitive N170 response is enhanced for nude bodies, PLoS One. 2011;6(11):e24408

[9] Christine Matzke, Susanne Muehleisen, Postcolonial Postmortems: Crime Fiction from a Transcultural Perspective, Rodopi, 2006

[10] What are some reasons why someone would want to hide their identity?

[11] David Numeroff, Laura Joffe Numeroff, Why a Disguise, Turtleback Books, 1999.

A modified version of the post with some speculations on human evolution can be found on naktiv.net or DeviantArt.