Not a proverb, not an aphorism. Not the Ten Commandments. The earliest message that has come down to us through the generations was scratched onto an ivory comb and it reads “May this tusk root out the lice of the hair and the beard”.
Six millennia earlier, forebears of the comb’s owner were mummified with nits in their hair. More recently, poignantly, a young Inca girl, chosen for ritual sacrifice, was taken 6700m up into the Andes, drugged and buried alive with rich grave goods. Her body, and the nits in her hair, were perfectly preserved by the dry volcanic soil of the Atacama Desert.
Head lice have been feeding on human scalps since before recorded history began. One hundred million years ago lice were troubling feathered dinosaurs, and they have evolved in parallel with their changing hosts. About 1.7 million years ago our ancestors lost their body hair, so lice had nowhere to live except on their heads. When humans felt the chill of an ice age, they started wearing clothing, and some head lice evolved to body lice to share the shelter. Thanks to scientific analysis of lice, we estimate that date at around 170,000 years ago. And the ability of lice to adapt to new hosts provides a model determining how emerging infectious diseases may affect humans.
