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DNA sequencing of 20 ancient bone fragments from Siberia's Denisova Cave revealed Yak X, an unknown Ice Age bovine lineage that diverged from modern yak ancestors around 400,000 years ago. 

About Denisova Cave   

  • Location: Situated in the Anuy River valley in the Altai Krai/Altai Mountains region of Siberia, Russia.  

  • Significance: Famous for yielding the first physical remains of the Denisovans (Homo sapiens altaiensis), an extinct species/lineage of archaic humans. 

  • The "Three-Species" Site: It is the only known archaeological site in the world proven to have been inhabited at different times by three distinct human groups:

    1. Denisovans

    2. Neanderthals

    3. Early Modern Humans (Homo sapiens)

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  • Denny (F11 Hybrid): In 2018, researchers discovered a bone fragment ("Denny") belonging to a 13-year-old girl who was the direct first-generation offspring of a Neanderthal mother and a Denisovan father, providing direct evidence of interbreeding between archaic human species.  

  • Timeline of Occupation: The cave layers contain artifacts and hominin deposits spanning about  300,000 years, making it the oldest continuously/repeatedly inhabited cave in Siberia.  

  • Artifacts & Culture: It has yielded advanced Upper Paleolithic artifacts, including bone points, animal-tooth pendants, and a polished greenstone bracelet.

About Yak X

Yak X is a provisional name given by researchers to a newly discovered, extinct Ice Age mammal identified through ancient DNA extracted from fossil bone fragments in Siberia's Denisova Cave and nearby regional sites.

  • Timeline: The fossils date from roughly 250,000–200,000 years ago to 27,000 years ago. 

  • Evolutionary Lineage: Its evolutionary lineage diverged from the ancestors of modern yaks approximately 400,000 years ago—a split roughly concurrent with the divergence between polar bears and brown bears. 

  • Ecological Significance: It coexisted with other megafauna of the Pleistocene mammoth steppe, including steppe bison, aurochs, woolly mammoths, and woolly rhinoceroses, and may have been hunted by Denisovans. 

Source: MONEYCONTROL

PRACTICE QUESTION

Q. With reference to the "Denisova Cave", frequently mentioned in archaeological and paleoanthropological studies, consider the following statements:

  1. It is located in the Altai Mountains of southern Siberia, Russia.

  2. It is the site where the extinct hominin group known as the Denisovans was first discovered.

  3. Fossil remains excavated from the cave provide evidence of hybridization between Neanderthals and Denisovans.

Which of the statements given above are correct?

(a) 1 and 2 only

(b) 2 and 3 only

(c) 1 and 3 only

(d) 1, 2, and 3

Answer: (d)

Explanation:

Statement 1 is correct: Denisova Cave is situated in the Altai Mountains of southern Siberia, Russia, near the border with Mongolia, China, and Kazakhstan.

Statement 2 is correct: It is the type locality where the extinct hominin group known as the Denisovans was first identified and named following DNA analysis of a juvenile female finger bone discovered in 2010.

Statement 3 is correct: Fossil remains excavated from the cave (such as the bone fragment known as "Denny" / Denisova 11) provided direct genetic evidence of an F1 hybrid offspring born to a Neanderthal mother and a Denisovan father.