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Elena Roché: Mother and Child, Morning Games (Charcoal on Velour Board, 2006) |
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Elena Roché: Mother and Child, Morning Games (Charcoal on Velour Board, 2006) |
What mommy told us |
| Anytime we discuss technical and cultural achievments of our noble genus Homo sapiens, we focus our attention on daunting feats, starting with the pyramids of Egypt and ending with the flight to the moon. However, exceptional events like these will have been hardly of any relevance during the evolutionary establishment of human culture and tradition. Likewise, the training of sophisticated skills as e.g. the artistic accomplishments of a concert pianist, most likely did not contribute to the survival of the human race. The biological roots of our behavior trace back to times when we still led the modest lives of technologically old-fashioned hunters and gatherers. In these times, cultural and technical tradition meant literally to do what you had been told to do, and nothing but you had been told. |
| If these last remarks reminded you vaguely about your own childhood, you're on the right track. In a recent commentary, the paleoanthropologist Dean Falk (2004) speculated on the origins of the behavioral feature most characteristic of Homo sapiens, of language. According to her hypothesis, the communication between a mother and her child is at the root of human language. In contrast to our closest relatives (the chimpanzees), bipedalism and furlessness prevented our hominin ancestors from carrying their babies around 24 hours a day. Before the advent of baby slings (a relatively modern invention in parallel to clothing, but this is a matter of debate), mothers might have tried other tricks to reassure their ward of their continued presence, also in the absence of bodily contact. And the mother's voice may have been such a means to keep in touch over some distance. |
| Since during embryogenesis, the skull and the brain form concomitantly, the outer surface of the brain remains imprinted in the inner face of the brain case. As originally realized by Phillip Tobias, these lucky circumstances allow for the reconstruction of several characteristic neuroanatomical features of our ancestors. The archeological record allows already in Australopithecus the identification of 'prominences' over those parts of the frontolateral cortex, where a precursor of Broca's motoric language area should reasonably be expected. However, an analogue of a receptive language area in the inferior parietal lobule (comparable to Wernicke's area) is missing from these specimens. Interestingly, such a correlate of a receptive language area is only to appear with Homo habilis, at approximately the same time as deliberately fashioned stone tools first appeared in the archeological record (Tobias 1996). |
| While Tobias is in doubt if Australopithecus knew to speak without the neuroanatomical correlate of Wernicke's area, he strongly advocates the presence of 'cultural and linguistic behavior' in Homo habilis (dated to 2.2-2.3 million years ago). However, he admits that those brain regions subserving language in modern humans, may not necessarily have done so in our ancestors. It is well known that Broca's area is not only related to language but also contains representations of hand actions and orofacial gestures (Nishitani et al. 2005). The first appearance of both productive and receptive language areas in the brain of Homo may in fact be related primarily to the manufacture of tools, and language may have arisen only later, after a sufficient refinement of tool production. |
| Even the first primitive stone tools resulted from directed blows, requiring some degree of hand coordination ('stone knapping', Wynn 2002). However, the overall shape of these earliest artifacts was most likely not the result of intention. Explicit categories of tools (as e.g. hand-axes) appeared for the first time not before about 400.000 years ago, at the evolutionary transition from Homo erectus to archaic Homo sapiens (Wynn 2002). Only since then, Homo produced carefully worked artifacts requiring higher cognitive skills as shape recognition, image manipulation, mental rotation, and abstract, multi-modal treatment of memory contents. Very likely, only at that advanced cognitive level Homo was able to use words and to combine them according to general rules as typical for 'language'. |
| Nevertheless, the exchange of sounds between mothers and babies may have accompanied human development for millions of years, setting up our first semantic categories long before the advent of our first creative achievements. Since language is the sine qua non of our culture and tradition, the mother / child relationship may not only have laid the ground to language, but also to the beginnings of our civilisation. In light of these considerations, maybe we should ask ourselves: what makes up the essence of our cultural traditions? What we do read in the newspapers? Learn at school? Or what mummy told us when we were little-ones? |
| D.Falk (2004)
Prelinguistic evolution in early hominins: Whence motherese? Behav. Brain
Sci. 27: 491-541. N.Nishitani, M.Schürmann, K.Amints, R.Hari (2005) Broca's region: from action to language. Physiology 20: 60-69. P.V.Tobias (1996) The dating of linguistic beginnings. Behav. Brain Sci. 19: 789-798. T.Wynn (2002) Archaeology and cognitive evolution. Behav. Brain Sci. 25: 389-438. |
