Earliest tuberculosis found in 1/2MIL-year-old human fossil

William Atkins
Saturday, 08 December 2007 19:48

Science - Biology

An international group of scientists discovers evidence of tuberculosis (TB) in a human fossil found in Turkey that is about 500,000 years old. Scientists previously thought that TB first appeared in humans only a few thousands of years ago.                   

A human fossil from the cranial area (region of the skull) of a young male from the human species Homo erectus was found in the country of Turkey. A series of small (one to two millimeter sized) lesions were found etched into the cranium near the bone around the right eye orbit.

The shape and location of these lesions indicate that they are a form of tuberculosis that negatively affects the meninges of the brain—what is called Leptomeningitus tuberculosa.

The discovery is the oldest evidence of TB in humans. The species Homo erectus is thought by scientists to be the first species of humans to move out of Africa and spread northward.

Previously, scientists had found TB in Egyptian and Peruvian mummified humans that had once lived several thousands of years. This much older discovery of TB is important to the ongoing medical research on tuberculosis.

U.S. physical anthropologist John Kappelman, from the University of Texas (Austin) is one member of an international team from the United States, Turkey, and Germany who performed the research. They published the results of their research (“First Homo erectus from Turkey and implications for migrations into temperate Eurasia (p NA)”) in the December 7, 2007 online issue of the American Journal of Physical Anthropology (AJPA).

Co-authors of the study include Mehmet Cihat Alçiçek, Nizamettin Kazanc , Michael Schultz, Mehmet Özkul, Sevket Sen.

Homo erectus people were originally thought to be dark-skinned humans that migrated northward into colder climates from tropical climates in Africa. They produced less vitamin D as they moved further north into seasonal climates, which adversely affected their skeleton because they received less sunlight from the Sun (which produces vitamin D in the human body).

Darker skinned peoples contain more melanin in the skin pigment that more effectively blocks ultraviolet radiation (light) from the Sun, which is what produces vitamin D in the human body.

Leptomeningitus tuberculosa was found to be common in certain early-human peoples who shared the physical characteristic of being of darker skin color and of having moved from equatorial latitudes to more northern latitudes.

Kappelman states in the December 7, 2007 University of Texas article “Most Ancient Case of Tuberculosis Found In 500,000-Year-Old Human; Evidence Suggests Vitamin D Deficiency Endangers Migrating Populations” that, "Skin color represents one of biology's most elegant adaptations. The production of vitamin D in the skin serves as one of the body's first lines of defenses against a whole host of infections and diseases. Vitamin D deficiencies are implicated in hypertension, multiple sclerosis, cardiovascular disease and cancer."