His view, called ‘The Naked Love Theory’, will be published in the MIT Press Journal: Biological Theory this June.
In Naked Love: The evolution of human hairlessness Dr Giles argues that human nakedness has its origin in the ancestral mother-infant relation. Skin-to-skin contact between mother and infant was experienced as affectionate and pleasurable by the mother. This would have encouraged ancestral females to bear infants, which was essential for the infant’s survival because with the advent of bipedalism, infants could no longer hold onto the mother.
‘Hairlessness is ultimately the adaptive consequence of bipedalism. This is because ancestral infants lost their prehensile feet and therefore the ability to grasp the mother’s fur with their feet, something that other primate infants must do’, says Dr Giles.
‘Early bipedal mothers were thus under much pressure to use their newly freed arms to carry the infant. Carrying an infant, however, is hard work and requires much effort. Therefore, in ancestral times infants survived only if mothers had a strong desire to hold them. Some evolutionary mechanism was required to select for a strong maternal desire to hold the infant and this is where naked skin came into play’, he says.
Because of this contact, especially in breast-feeding—which many women report to be erotically pleasurable—the desire to hold the infant would have been stronger in mothers possessing a hairless mutation that also enabled them to give birth to hairless infants. Survival of these infants would have then been greater than hair-covered infants.
The hairlessness that began to appear through this mechanism of maternal selection, Dr Giles says, was then reinforced by sexual selection in the male-female sexual relationship. This is because a hairless sexual partner would have enabled the individual to recreate the pleasure of skin-to-skin contact that he or she had originally experienced as an infant.
According to Dr Giles, ‘It is not just nursing mothers who enjoy skin-to-skin contact. Infants who are breast-feed in full naked contact with the mother experience less problems, show less distress and breast-feed longer than infants who are separated from their mother by clothing.’
The Naked Love Theory’ also helps to explain the evolutionary origins of romantic love. ‘One thing that distinguishes us from our closest primate relative is the intensity and duration of sexual intercourse’, he says. ‘While sexual intercourse for chimpanzees typically lasts about seven seconds, with human beings it’s more like 10 minutes’.
One of the reasons for this, argues Dr Giles—who is also the author of The Nature of Sexual Desire—is the extensive caressing of naked skin that human beings typically enjoy in sexual intercourse due to our lack of fur. This provided the pre-condition for the extensive long-term romantic attachments that human beings are capable of. Although some other primates have long term attachments, our closest relatives tend not to have them or form only short-term consortships.
‘Numerous biological features were, of course, prerequisite for the emergence of romantic love, but without human nakedness and all that it entails for skin-to-skin contact, it is doubtful that romantic love as we know it would have ever appeared,’ he says.
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