And now for something completely different… This is a repost with a difference – it’s an edited interview I did with London scientist Chris McManus way back in September 2007. This has a fond place in my heart, for it was the first proper freelance writing assigment that I did after winning the Telegraph’s Science Writer award. This is where all the cool freelancing began. It was originally published on Nature Network, but I note that their news archives have disappeared. As such, here it is again.
McManus, a Professor of Psychology and Medical Education at UCL, is an expert on asymmetry and left-handedness. He won the Aventis Prize for Science Books in 2002 with his first book – Right Hand, Left Hand. Now, he’s turned his attention to the rise and fall of left-handedness during British history.
About 11% of the British population is currently left-handed. But that wasn’t always the case. Among people born in 1900, the proportion of lefties was just 3%. McManus and Alex Hartigan from University College London worked this out with the help of old films made at the turn of the 19th century and recently restored.
What made you want to study historical rates of left-handedness?
People have always assumed that the rate of left-handedness has been constant throughout history but it’s never been properly explored. Recent data showed us that left-handedness was less common in people born at the beginning of the twentieth century than those born later, by a factor of four.
We wanted to find out what happened before that and why things changed. But of course, there’s very little data. People have talked about left-handers in the literature since the time of Aristotle but they never say how many there were.
How did you find out?
It was a stroke of luck. We came across these wonderful films by Mitchell and Kenyon, made between 1900 and 1906, where they filmed people coming in and out of factories. They’re wonderfully evocative films. You really get a sense of that late Victorian era.
We noticed that the people in the films waved whenever they saw the camera. My student, Alex Hartigan, went through this footage and recorded every time someone waved and which hand they used.
Chimpanzees may not be able to recite Hamlet or giving rousing speeches but there is no doubt that they are excellent communicators. They exchange a wide variety of sophisticated calls and gestures that carry meaning and can be tailored to different audiences.
The sophistication of chimp communication doesn’t stop there. Jared Taglialatela from the Yerkes National Primate Research Center has found that chimp signals and human speech are both strongly influenced by the same area in the left half of the brain – a region called the inferior frontal gyrus (IFG).