Workers excavating a new subway line in downtown Mexico City in the late 1980s found a mass grave that was decades old. Records showed that the grave was once attached to a hospital established around 1530, about 10 years after the Spanish conquest of Mexico, to treat the region’s indigenous population.
As archaeologists excavated the site around 1992, they found that three skeletons stood out due to their filed front teeth which were similar to enslaved Africans from Portugal and people living in parts of West Africa.
Analyses are now suggesting that those three individuals were genetically male and among the first Africans enslaved in the Americas.
Using a combination of genetic, osteological, and isotope analyses, scientists have determined from where in Africa the three men were likely captured, the physical hardships they experienced as slaves, and what novel pathogens they may have carried with them across the Atlantic.
The findings have since been published in the journal Current Biology.
“Using a cross-disciplinary approach, we unravel the life history of three otherwise voiceless individuals who belonged to one of the most oppressed groups in the history of the Americas,” says senior author Johannes Krause, an archaeogeneticist and professor at the Max-Planck Institute for the Science of Human History.
During the 16th and 17th centuries, thousands of enslaved and free Africans lived in Mexico, and with this study, researchers will now be able to find more answers to questions about the roots of Mexican culture.
“Having Africans in central Mexico so early during the colonial period tells us a lot about the dynamics of that time,” says first author Rodrigo Barquera, a graduate student at the Max-Planck Institute for the Science of Human History. “And since they were found in this mass burial site, these individuals likely died in one of the first epidemic events in Mexico City.”
To confirm the origins of the three men, Barquera and Krause extracted genetic and isotope data from their teeth. “Their genetics suggest they were born in Africa, where they spent all of their youth. Our evidence points to either a Southern or Western African origin before being transported to the Americas,” says Barquera.
A closer look at their bones also shows that the three individuals endured malnutrition and physical abuse while in the Americas. One individual had a series of leg and skull fractures while another had several gunshot wounds. The three men, however, survived those abuses, according to the researchers.
“Within our osteobiographies we can tell they survived the maltreatment that they received. Their story is one of difficulty but also strength because although they suffered a lot, they persevered and were resistant to the changes forced upon them,” Barquera says.
All three men died between the ages of about 25 and 35, and researchers are still not sure what killed them. Even though they were buried in a mass grave in a hospital’s cemetery that could be linked to an epidemic, researchers did not find DNA from deadly infectious diseases in their remains.
They, however, found the genetic material of two pathogens that infected two of the individuals while they were alive. “We found that one individual was infected with hepatitis B virus (HBV), while another was infected with the bacterium that causes yaws–a disease similar to syphilis,” says co-senior author Denise Kühnert, a mathematician working on the phylogeny of disease, from the Max-Planck Institute for the Science of Human History.
“Our phylogenetic analyses suggest that both individuals contracted their infections before they were likely forcibly brought to Mexico.”
Kühnert says that it’s plausible that yaws, which was common in Mexican people during the colonial period, “was not only brought into the Americas through the transatlantic slave trade but may subsequently have had a considerable impact on the disease dynamics in Latin America.”
“We want to get insights into how pathogens emerged and spread during the colonial period in the New Spain, but we also want to continue to explore the life stories of the Africans brought here and other parts of the Americas. That way they can take a more visible place in Latin American history,” says Barquera.
In effect, Hannes Schroeder, an archaeologist at the University of Copenhagen who wasn’t involved in the research, says the study “reminds us once again of the cruelty of the trans-Atlantic slave trade and the biological impact it had on individuals and populations in the New World.”