| Elahe Izadi |
YOU probably don’t spend much time thinking about how curious it is that your mother looks dra-matically different from your boss, whose face doesn’t at all resemble your mail carrier’s, let alone your fourth grade teacher’s or your prom date’s or that barista’s at the coffee shop.
But in the grand scheme of things, the massive variation among human faces is quite extraordinary when compared to animals that pretty much all look the same.
As it turns out, evolutionary pressures for individuals to be easily recognisable pushed us toward having widely different faces, according to a new study published in Nature Communica-tions and funded by the National Institutes of Health.
“Individual recognition is real-ly important, in some ways so important that sometimes we don’t realise how we recognise individuals,” said study co-author Michael Sheehan, a postdoctoral fellow at University of California, Berkeley’s Museum of Vertebrate Zoology. “It’s so ingrained within us.”
The study found that there’s more variation in human facial traits – such as the distance be-tween eyes or the length of a nose – than there is for other body traits.
And facial traits aren’t connec-ted to each other the way other body traits are; someone with long legs tends to have long arms. But you can have close-set eyes and either a wide nose or a small nose. Faces are unpredictable like that.
Researchers turned to two data sets to discover the variance: The Army Anthropometric Survey, which includes measurements of men and women and is often used to design things like clothes, and the 1000 Genomes Project, which has mapped out the genomes of nearly 1,000 people.
While the relationship between our genes and certain traits (like height) are quite reliable, the re-searchers found the genes that influence facial features to be less straightforward. WP-BLOOM