Ancient Microbiome Unearthed from 1,000-Year-Old Remains in Mexico

The remarkably preserved remains of a 1,000-year-old man discovered in a cave in central Mexico have offered researchers an extraordinary insight into the ancient human gut microbiome. The individual, referred to as the Zimapán man, was naturally mummified due to the cave’s unique conditions in Zimapán, a region bordering Mesoamerica and Aridoamerica. His burial, which included an elaborate funerary bundle, suggests he played a significant role in the Otopame culture, a group of extinct hunter-gatherers.

Researchers highlighted the importance of this discovery in a recent study published in PLOS One, noting that the preserved intestinal tissue and fecal remains reveal a detailed portrait of the microbiome present in this ancient individual. The findings potentially provide insights into his life and underscore the sophistication of the culture from which he originated.

Significant Discoveries from the Past

The journey to uncover the Zimapán man began in 2014 when residents of El Saucillo, Zimapán, stumbled upon the mortuary bundle in a rock shelter that created ideal conditions for preservation. According to Santiago Rosas-Plaza of the National Autonomous University of Mexico, the remains included soft tissues, fragments of the intestinal wall, fecal matter, and blood vessels.

Using standard analytical methods, researchers identified the individual as male, who likely died between the ages of 21 and 35. His burial included layers of maguey fiber mats and woven cotton, indicating he was likely a person of importance in his community. “The outer layer of the bundle was made of a mat woven from long maguey fibers, providing a strong yet flexible covering,” stated Rosas-Plaza.

Insights into Ancient Microbiomes

In analyzing the mummified intestinal tissue and preserved feces, the team employed 16S rRNA gene sequencing to identify the types of bacteria present. Their findings revealed several families of bacteria, including Peptostreptococcaceae, Enterobacteriaceae, and Enterococcaceae, which have long-established symbiotic relationships with humans.

Notably, signs of bacteria from the Clostridiaceae family had previously been found in mummies from ancient Andean civilizations, linking the Zimapán man to a broader cultural context. The discovery of Romboutsia hominis in this ancient microbiome is particularly significant, as it had never been documented in previous studies, marking a pivotal moment in the research of microbial evolution.

The study authors concluded that the integration of data from anthropology, archaeology, and microbiome analysis offers a powerful approach to unraveling human evolution and its intricate relationships with biological and social environments. They suggested that the Zimapán paleofeces could contain authentic ancient gut bacteria, providing a window into dietary practices and health in ancient cultures.

The exceptional state of preservation of the Zimapán man reflects the cultural practices of his time. The researchers noted the mathematical composition of the knots within the burial fabric, indicating a complex arrangement that required considerable skill. Master Luisa Mainauo, who oversees the mortuary bundle, has dedicated nearly eight years to restoring it, aiming to share this significant piece of history with both the people of Mexico and the global community.

This groundbreaking research not only expands knowledge of ancient microbiomes but also highlights the intricate social structures of early human societies, marking a significant contribution to the understanding of our shared history.