How Did Head Lice Begin?

In an attempt to answer the question, “How did head lice begin?” scientists are studying the DNA of head lice. The DNA is extracted from the mitochondria of the head lice cells and used to reconstruct the ancestry of these parasites. They have found a link between head lice and humans dating back at least two million years, when a common lineage called Clade A split into two subgroups, Clade C and Clade B. The DNA of lice is relatively pure compared to the DNA of human beings, so scientists believe that head lice can provide important clues about human evolution.

Head lice are parasitic insects, meaning that they feed on the blood of their host. These parasites survive in human hair and are only known to attack the scalp. In the past, head lice and body lice were similar, but they evolved over time to latch onto human hair and clothing fibers. As a result, head lice and body lice have become a worldwide problem.

The life cycle of the head louse is dependent on the environment. The most common environment for head louse infestation is close head-to-head contact. Objects can also be a possible source of transmission, although this is rare.