Denisovan DNA in Tibetan Cave Changes History of Early Humans in Asia

An international team has found evidence that could change our understanding of a mysterious species of early humans, the Denisovans. They have found DNA from these humans in a Buddhist cave on the Tibetan Plateau in China.

These finds are adding to experts’ knowledge of the mysterious Denisovans and how they interacted with modern humans as they migrated into Asia.

The Baisiya Karst Cave is approximately 10,400 feet (3,200 m) high on the rugged Tibetan Plateau. For the local Buddhist monks, the cave is a sacred site. Many years ago, a mysterious lower jawbone (mandible) was found in the cave and it has recently been re-examined. In 2019 researchers proposed it belonged to a Denisovan, but this was disputed.

Denisovans: Relatives of Modern Humans

About 40,000 years ago, this species of archaic human lived across Asia. A close relative of Neanderthals, the Denisovans even interbred with our ancestors.

Many modern Australasians and Asians have Denisovan ancestry. Almost no remains of the hominins have been found outside of the Denisova Cave in Siberia, after which the species is named.

Because of the scarcity of remains, the jawbone could provide precious insights into the extinct archaic human species. However, the only evidence that it was Denisovan was “based on a single amino acid position,” reports Cosmos.

Archaeologist Dongju Zhang of Lanzhou University and her colleagues wanted to prove once and for all that the jawbone was from a Denisovan and sought DNA which would be used as conclusive proof.

Excavations in Sub-Zero Temperatures

In the winter of 2018, they worked with an international team on an intensive investigation of the cave. This excavation was terribly challenging. Because the cave is sacred to local Buddhists, the team could only work at night so as not to disturb the faithful during the day. They also had to remove all traces of their work before the morning and often worked in temperatures as low as –18°C (-0.4°F).

The experts dug deep into the soil of the cave. While they did not find any hominin bones, they found something even better: traces of mitochondrial DNA. This is a hugely important discovery. According to Science “Zhang’s team reports the first Denisovan ancient DNA found outside the Denisova Cave : mitochondrial DNA (mtDNA) gleaned not from fossils, but from the cave sediments themselves.”

This is the first time that genetic evidence for the Denisovans has been found outside Siberia. The DNA was extracted from human remains in the topsoil. This was probably left behind in the poop and urine of the Denisovans.

Early Humans in Tibet

Bo Li of the Australian University of Wollongong told Cosmos that they have “detected ancient human fragments that matched mitochondrial DNA associated with Denisovans in four different layers of sediment deposited.” The sediment where the DNA has been dated to around 100,000 and 60,000 years ago and possibly as “recently as 45,000 years back, the time when modern humans were migrating to the eastern part of Asia,” reports News Click .

These findings change the history of early humans in Asia. The researchers wrote in Science that the DNA “extends the time of occupation of the Tibetan plateau by hominins.” Li and his colleagues were able to date the finds by using optical dating, which works by showing when they had been exposed to light.

By showing that DNA and dates can be gathered from sediment, this groundbreaking research is paving the way for “a new era of molecular caving,” explains Katerina Douka of the Max Planck Institute in Science.

The find is important because it is the first DNA to have been found outside the Denisovan Cave in Siberia. Unearthed some 1200 km from Siberia, the discoveries in the soil of the cave end a long search for Denisovan DNA outside of Siberia. They also provide further evidence that Denisovans were once widespread across Asia.

Denisovan “Superathlete” Gene

But DNA wasn’t all they found. The team also unearthed several artifacts and other remains in the holy cave, as well as a great deal of charcoal which proves that the Denisovans used fire. Moreover, the experts found over 1,300 rudimentary tools and many animal bones, including some from hyenas and rhinos, both of which once roamed Tibet. It has also been speculated that they used the cave as a lookout from which to watch out for prey on the meadows below.

Finding the remains of Denisovans at such an altitude shows that the ancient species could cope with a range of environments and that they were highly adaptable. This ability was inherited by modern Tibetans, allowing them to survive in one of the world’s toughest environments.

Modern Tibetans inherited from the Denisovans “a ‘superathlete’ variant of a gene, called EPAS1,” explains Science. However, it only spread widely in the last 5,000 years and may indicate that the extinct archaic humans only lived seasonally in the cave.

More finds are expected to be made at the Baishiya Karst Cave site. Li told Cosmos that their “next target is to date more samples from the cave and try to answer when Denisovans started to occupy the cave and when they ‘disappear’ from the cave.” This could be crucial in understanding modern humans’ interactions with the archaic hominins and perhaps even solve the mystery of their extinction.

2,200-Year-Old Stone Armor Reveals Qin Shi Huang’s Legacy

Excavations in 1998 and 2019 unearthed hoards of ancient stone armor in and around the Mausoleum of Qin Shi Huang, offering insights into the emperor’s military achievements and life. Now, a new study highlights how these discoveries represent various aspects of Qin Shi Huang’s military legacy.

In 1998, archaeologists in China discovered a stash of ancient stone armor in ‘Pit K9801 ,’ in the Mausoleum of the First Qin Dynasty Emperor, Qin Shi Huang, who ruled in the central Shaanxi Province from 221 to 210 BC.

Famous for having united China under a centralized imperial government, Qin Shi Huang constructed the Great Wall of China and commissioned the famous Terracotta Army as part of his elaborate tomb complex .

Digging Beneath the Money Tree

In 1998, archaeologists unearthed over 600 small limestone plates, which were connected to each other using bronze wires. In 2001, further stone armor products, and the tools used to make them, were found in a well in Xinfeng, by the Wei River, that dated to the Qin Dynasty .

Then, in 2019, archaeologists from the Shaanxi Academy of Archaeology excavated the Liujiagou site , beneath the barren bush to the north of the main burial site, near a high-rise building in Xianyang, the capital city of the Qin Dynasty.

Even more defective stone armor and tools were found, and all of the findings matched the previously excavated stone armor remains from Pit K9801, and from the site in Xinfeng.

Analyzing “32,292” Ancient Artifacts

A new study published in Science Direct, by professor Xuewei Zhang of the Bioarchaeology Laboratory, Jilin University , Changchun, says the 2019 discovery “is significant,” because it links two phases of Qin Shi Huang’s life and death. Furthermore, these archaeological finds illustrate funerary and burial processes within the Mausoleum of the First Qin Emperor.

In 2019, the team of archaeologists excavated an area of 144 m2, (1,550 sq ft) revealing a hoard of “32,392 artifacts,” according to the study. Some stone armor plates were rectangular in shape with drilled holes, polished surfaces, and treated edges, and “almost finished,” resembling previously excavated stone armor.

Furthermore, the artifacts represented a specific type of stone armor, and included production waste.

Tellingly, the team of archaeologists also discovered tools that were used in the production of the stone armor, which informed the researchers about the manufacturers craft skills and production methods. The new paper focuses on the production process of stone armor, and it breaks the methods down into its different stages.

Almost Finished Stone Armor

Stone armor consists of front and rear tunics, pauldrons, and a tasset. The new analysis revealed the use of high-quality limestone with minimal joints as the raw material, and the researchers matched some “nearly finished,” broken plates, to their original armor sets.

The scientists also experimented with the wear patterns to better understand the perforation techniques used in making the stone armor. And after reconstructing the stone armor production process, the researchers found that the armor “was abandoned” before completion.

According to the new study, evidence suggests the process of making stone armor was similar to that of producing leather armor, by casting molds.

Furthermore, the stone armor production process consisted of “nine repetitive steps, potentially influenced by random variables.” And the new study also showed that the raw materials used to make the armor, “were not local but imported from distant locations”.

Stone Armor, For Afterlife Battles

The new study concluded that the 2019 excavation site was “a significant stone armor workshop during the Qin Dynasty.” However, in the practical world, stone armor offers limited protection, and is easily damaged when impacted, therefore it was unsuitable for use in combat.

Stone armor was used in ancient China to preserve grave goods during funerals, “because it decayed less rapidly than leather armor,” according to the new paper.

2,200 years ago, in China, stone armor was made primarily for funerary purposes, rather than for actual use in battles, but it imitated the style of armor used at that time.

Despite its practical limitations, the inclusion of stone armor and stone weapons in burials, such as that of Qin Shi Huang, the first emperor of the Qin Dynasty, reflected the people’s reverence for all things military, and each piece of stone armor reflects the military power and authority wielded by various rulers during their lifetime.