Researchers from the Florida Museum of Natural History study offer some new studies on how parasitical lice and vitamin-producing bacteria tend to make them end up sucking primates and humans.

Interestingly, bacteria live inside lice and provide their host's essential vitamins that are not present in human or primate blood. Hence, these bacterial partners are part of specialized cells within their insects. They can be transmitted from their female lice to their offspring. It is important for both the lice and their bacteria to live with each other. The lice wouldn't remain alive without the bacteria, which would not live outside their insect hosts either.

It is not clear how lice and bacteria evolved their relationship. Still, it has been found that lice acquired and took the place of their bacterial symbionts many times through the centuries.

The Florida Museum researchers Bret Boyd and David Reed discovered that the lice and bacteria have parasitized both apes and humans and also harbored the endosymbionts for more than 20 to 25 million years. Interestingly, this is the time during which the great apes and early monkeys actually had a common ancestor, according to Phys.org.

Hence, the lice and bacteria have evolved together. The lice seem to have evolved along with the primates. The evolution of the lice happened with that of the bacterial symbionts.

Boyd, who undertook the research as a doctoral student at the museum, clarified that the information gives new insights into the evolution of these symbiotic lice and bacteria. Currently, he is a postdoctoral researcher at the University of Georgia and the study's first author.

Boyd noted that even though lice and bacteria are "highly maligned" they offer a huge fount of scientific information. As the symbiotic bacteria are closely associated with a known evolutionary history between the insects as well as the apes, they also offer a conductive system for the research of the bacterial genome evolution, according to Science Daily.

Many species of blood-sucking lice and bacteria tend to live off just a single species of host. This is a specificity that gives insights into primate and human evolution, said Reed, curator of mammals and associate director of research and collections at the Florida Museum.

"Certain parts of our history are murky and hard to reconstruct," he said. "The evolution of lice and their symbiotic bacteria helps shed light on human and primate evolutionary history, providing new clues to our past."

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