The identification of a new human group called the Denisovans has been one of the most exciting discoveries in human evolution over the past decade. Unlike Neanderthal remains, the Denisovan fossil record consists of only a few skeletal fragments. Several Denisovan populations, which likely had vast geographic ranges, adapted to different environments and through multiple different interbreeding events that helped shape early human history, according to a new study. I passed on some of my genes.
Portrait of a young Denisovan woman based on a skeletal profile reconstructed from ancient DNA methylation maps. Image credit: Maayan Harel.
Denisovans are an extinct hominin group first identified through genome sequences determined from finger bone fragments found in the Denisova Cave in the Altai Mountains of southern Siberia.
“This was one of the most exciting discoveries in human evolution in the past decade,” said Dr Linda Ongaro, a researcher at Trinity College Dublin.
Subsequent genome analysis showed that Denisovans diverged from Neanderthals 400,000 years ago, and that at least two distinct Denisovan populations intermingled with the ancestors of modern Asians.
The only physical remains of Denisovans discovered so far are a finger bone fragment, three teeth, and a skull fragment from the Denisovan Cave. Jaw bones and rib bones from Baisiya Karst Cave on the northeastern edge of the Tibetan Plateau.
“It's a common misconception that humans evolved suddenly and cleanly from one common ancestor, but the more we learn, the more we realize that interbreeding with different hominins occurred and helped shape the humans we know today. ” said Dr. Ongaro.
“Unlike Neanderthal remains, the Denisovan fossil record consists only of finger bones, jaw bones, teeth, and skull fragments.”
“However, by exploiting the remaining Denisovan parts of modern humans' genomes, scientists have found evidence of at least three past events in which genes from different Denisovan populations invaded modern humans' genetic characteristics. I discovered.”
Each of these shows different levels of relatedness to the sequenced Altai Denisovans, illustrating the complex relationships between these sister lineages.
Dr. Ongaro and his colleague Professor Emilia Huerta Sánchez of Trinity College Dublin and Brown University, in their new paper, have a wide geographical range, from Siberia to Southeast Asia, and from Oceania to the south. We have reviewed evidence pointing to several likely Denisovan populations. America has adapted to a unique environment.
They also outlined a number of genes of Denisovan origin that conferred advantages to modern humans in different environments.
“Among these are genetic loci that confer tolerance to hypoxia or hypoxic conditions, which makes a lot of sense because we see it in the Tibetan population. Multiple genes that increase immunity. Another “Influences lipid metabolism and provides heat when stimulated by cold, providing benefits to Arctic Inuit populations,” Dr. Ongaro said.
“There are many directions for future research that will help us more fully understand how Denisovans influenced modern humans, including uncovering currently hidden traces of Denisovan ancestry. This includes more detailed genetic analyzes in understudied populations that have the potential to
“Additionally, by integrating more genetic data with archaeological information, finding more Denisovan fossils will certainly fill in some more gaps.”
of paper Published in a magazine natural genetics.
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L. Ongaro & E. Huerta-Sánchez. History of multiple Denisovan introgressions in modern humans. Nat Genetpublished on November 5, 2024. doi: 10.1038/s41588-024-01960-y
Source: www.sci.news
