When an Ear Witness Decides the Case

[elleng]

In ways that researchers are just beginning to appreciate, we humans are beholden to our ears. Mechanically, electrically, behaviorally and cosmetically, our paired sounding boards are a genuine earmark of our species. And if the words aural and oral are often confused, they should be, for our ears and our mouths jointly gave us our voice.

Scientists now suspect that the origin of human language owes as much to improvements in the early hominid ear as to more familiar spurs like a changing vocal tract or even a generally expanding brain. In one recent molecular analysis, John Hawks of the University of Wisconsin reported that eight genes involved in shaping the human ear appear to have undergone significant changes over the past 40,000 years, some as recently as the dawn of the Roman Empire. Only with highly refined auditory infrastructure, researchers said, could our ancestors have tuned in to the sort of tiny fluctuations in pressure waves that characterize all human speech, let alone properly conjugated Latin.

Moreover, the avidity with which our auditory sense seeks to organize ambient noise into a meaningful acoustical pattern — a likely consequence of our dependence on language — could help explain our distinctly human musicality.

http://www.nytimes.com/2009/06/23/science/23angi.html?th&emc=th