ABOVE: A broken strand of human hair with an uneven end
WEN YANG
Astudy of eight types of mammals suggests that thin hair tends to be stronger than thick hair due to the way it breaks.
Wen Yang, a materials scientist at the University of California, San Diego, and colleagues stretched and broke individual hairs and studied them under a scanning electron microscope. Thick hairs with a diameter of more than 200 μm, such as those of boars, giraffes, and elephants, tended to split in a clean break, while thinner hairs from humans, bears, and horses sheared unevenly.
The researchers write in their study that they believe the difference in breaking pattern has to do with hair diameter. In thicker strands, an initial tear is small in relation to the hair’s diameter. This favors a regular fracture with a clean break. But in thinner hairs, the relatively large size of the ...