Ancient genomes reveal legacies of human sacrifice and medieval epidemics

Sub: Science and tech

Sec: Biotech

Context:

In a recent scientific report published in Nature, a team of archaeologists and scientists from Germany, Mexico, Spain, the U.K., and the U.S. sequenced genetic material obtained from the human remains.

More on news:

Scientists have used archaeogenetics and evolutionary medicine to bring to light some of the inner lives and beliefs of the Mayan people.
People’s practice of burying human remains throughout modern history echoes diverse cultural, spiritual, and social beliefs, and is often considered to be a line in the sands of time between modern and ancient humans.
They read the results along with bio-archaeological evidence collected at the site to launch an extensive investigation of the remains of 64 sub-adults from the Sacred Cenote and compared them to modern-day individuals of Mayan origin.

Key findings of the study:

Their studies revealed that all sub-adults in the cenote were genetically male and closely related to each other.
The findings go against 20th century colonial accounts that claimed young women had been sacrificed here.
The study also identified two pairs of monozygotic twins among the remains.
Twins held significance in Mayan spiritual life and were linked to the underworld.
The researchers also used isotopic studies to establish that all the related individuals in the cenote had similar diets, suggesting they all belonged to the same household.
The similarities also suggested they were selected for a specific purpose.
It is widely believed the Mayans organized ritual sacrifices to ensure the bountiful growth of maize and to appease rain gods.

Benefits of the study:

By comparing the ancient and the modern genomes from Mexico, the researchers found evidence of positive selection in genes related to immunity, especially those associated with resistance to enteric fever caused by Salmonella enterica Paratyphi C, a pathogen serotype previously identified with the 16th century cocoliztli epidemic in Mexico.
The study of the ancient genomes and their modern counterparts allows us to resolve old mysteries, dispel old hypotheses, and gain new insights from the past to light the way for the future.

Practice of Burying:

Researchers have recorded the practice of burying since the time of our now-extinct Neanderthal ancestors.
The oldest intentional modern human burial dates to more than 100,000 years ago, in a cave in Israel.
This timeline overlaps with the discovery of the skeletal remains of a roughly three-year-old child buried in Kenya some 80,000 years ago.
Burial practices evolved with advancing human civilisations, with the construction of elaborate mausoleums.
The pyramids of Egypt were monumental tombs for the pharaohs; the Mughal emperor Shah Jahan commissioned the Taj Mahal in Agra as a mausoleum for his wife.
These structures reflect an enduring human desire to honor the dead and remember them.

Ancient Mayan genomes:

Chichén Itzá is an ancient Mayan city located in modern-day Mexico.
It is known for its grand architecture and iconic ceremonial temples, built around 800-1000 AD.
The temples are also infamous for having been the site of human sacrifices made as ritual offerings, and have been under constant archaeological investigation for more than a century.
The offerings were deposited in an enormous sinkhole or a subterranean cistern called the ‘Sacred Cenote’.
In Mayan culture, these subterranean features were often associated with water and rain.
The Sacred Cenote in Chichén Itzá holds the skeletal remains of more than 200 ritually sacrificed individuals, many of them children or adolescents.