Young Brunette Girl With Long Hair Reveals Her Tanned Body At Home

The eyelash grows at the edges of the eyelid and protects the eye from dirt entering the eye. Camels have particularly long and thick eyelashes. The eyelash is to humans, camels, horses, ostriches etc., what whiskers are to cats; they are used to sense when dirt, dust, or any other potentially harmful object is too close to the eye. The eye reflexively closes as a result of this sensation.
Evolution
A 2008 study by scientists from the Medical University of Vienna traced the origins of hair to the common ancestor of mammals, birds, and lizards that lived 310 million years ago. The study found chickens, lizards, and humans all possessed a similar set of genes that was involved in the production of alpha keratin. In chickens and lizards, the α-keratin produced was found in their claws, but in mammals it was used to produce hair. The scientists involved continued searching for the mechanisms that allowed mammals to use the keratins of animal claws to produce hair.