Lice DNA Supports Biblical Account of Humanity’s Creation
Every parent dreads receiving a note from their children’s school announcing an outbreak of lice. Messages of this sort set in motion a series of unpleasantries for the child, parent, and sometimes the rest of the family.
Some anthropologists, however, take a certain delight in lice infestations. These obligate surface parasites, and their genetic variability, offer insight into human origins and the migration of the first people around the world.
Most scientists who study lice are interested in these parasites for biomedical reasons. For example, some choose to focus on the natural history of these disease-causing organisms. Learning about the timing and location of lice origins, the historical pattern of their spread, and consequently, the contemporary distribution of their genetic variation helps biomedical researchers understand how infectious diseases harbored by insects spread. This information can potentially lead to more effective public health programs and, in some cases, treatments.
In the process of studying the origin and natural history of human parasites, like lice, molecular geneticists have stumbled upon an exciting new way to characterize humanity’s origin and movements around the world. Researchers believe that the timing and location of the origin, as well as the spread, of disease-causing and disease-harboring pests around the world mirrors the timing and location of the origin and spread of humanity. As such, the worldwide genetic variation of these infectious agents can be used in the same way that molecular anthropologists use human genetic variation to gain understanding of human prehistory.
A remarkable study on the global circulation of head lice illustrates how this creature can be used to track the spread of humanity around the world.*
There are three types of head lice (based on genetic fingerprints) distributed around the world: types A, B, and C. Type A is found throughout the world. Type B occurs in North and South America, and Europe. Type C is rare and geographically restricted to Ethiopia and Nepal.
Some investigations posit that Type A head lice established its association with modern humans in Africa shortly after the first people appeared. Type B originated in Europe after humanity spread into Asia and then Europe. Accordingly, Type B head lice appeared in the New World when Europeans colonized the Americas. If this model is correct, then Native Americans would have carried Type A head lice with them when they originally migrated into the Americas from Asia.
Researchers recognized a unique opportunity to test this model with the discovery of pre-Columbian mummies in Peru, dating to about 10,000 years in age, well before the Spanish and Portuguese arrived.
Anthropologists were able to recover the remains of ancient lice from the hair of the mummy. They then successfully extracted DNA from the lice specimens, then amplified and sequenced it. The lice possessed the Type A DNA fingerprint. This result means that the first immigrants into the Americas most likely carried the same genetic version of lice as the first humans in Africa. Type B lice must have been introduced by European settlers.
The natural history of lice matches the expected pattern of the Out-of-Africa hypothesis for human origins. Though often presented and discussed within the context of the evolutionary paradigm, this model has profound biblical implications. This hypothesis, which is substantiated by numerous studies, maintains that humanity originated recently (about 100,000 years ago) from East Africa (near the location theologians ascribed to the Garden of Eden) from a small population. Studies using mitochondrial and Y chromosomal DNA markers trace humanity’s origin back to a single man and woman. The genetic data also indicate that humanity’s migration around the world began at or near the Middle East.
If humanity’s genesis happened in the way described in Scripture, the genetic diversity patterns observed among international people groups would be very similar to those discovered by anthropologists. It looks as if Adam and Eve really existed, giving rise to all humanity.
For a detailed discussion of the myriad evidence in favor of the Out-of-Africa hypothesis and the use of parasites to characterize the origin of humanity see my book Who Was Adam?
*This study made science news headlines when first published. I discussed the scientific and biblical implications of this research on the February 11, 2008 edition of our new podcast, RTB’s Science News Flash. This podcast offers a unique Christian perspective on headline-grabbing discoveries. A free subscription is available through iTunes.