Head Lice begin their journey into the world as an egg or nit. These whitish-yellow specs are as small as one millimeter in length and they’re highly skilled at attaching themselves to individual hair strands close to the scalp. After roughly seven-to ten-days, a nit hatches and becomes a young louse or nymph. Nymphs mature into adult lice after about nine-to-twelve days, growing no larger than two millimeters in size. While head lice are known to crawl relatively quickly, they do not have the ability to hop, fly or jump on your hair follicles. Since lice live and breed completely in human hair, they typically only survive for up to one or two days before they drop off of your head or die from malnourishment. Adult lice cannot live longer than twenty-four hours on nonhuman surfaces such as hardwood floors, clothing and furniture.