Sangiran skull replica 17 Homo erectus de Java Crédit: Photo provided by the administrators of the Natural History Museum

In the study published in Nature Ecology and Evolution, researchers examined the genomes of more than 400 modern humans to study the interbreeding events between ancient humans and modern human populations that arrived on the island of Southeast Asia ago 50 000 at 60 000 years.

Un groupe international de chercheurs comprenant des experts du Muséum d’histoire naturelle et dirigé par l’Université d’Adélaïde a mené une analyse génétique complète et n’a trouvé aucune preuve de métissage entre les humains modernes et les anciens humains connus à partir des archives fossiles de l’île d’Asie du Sud-Est. L’équipe a trouvé d’autres preuves ADN de nos mystérieux anciens cousins, the Denisovans, which could mean that there are major discoveries to come in the area.

In the study published in Nature Ecology and Evolution, researchers examined the genomes of more than 400 modern humans to study the interbreeding events between ancient humans and modern human populations that arrived on the island of Southeast Asia ago 50 000 at 60 000 years.

In particular, they focused on detecting signatures suggesting crosses of deeply divergent species known from the region's fossil record.

The region contains one of the richest fossil records (at least 16 million years) documenting human evolution around the world Currently, there are three distinct ancient humans recognized from the fossil record in the area: Standing man, Homo floresiensis (known as the Flores Island Hobbits) and Homo luzonensis

These species are known to have survived until about 50 000 at 60 000 years in the case of Homo floresiensis and Homo luzonensis, and around 108 000 years for Homo erectus, which means they may have overlapped with the arrival of modern human populations.

The results of the study showed no evidence of interbreeding, however, the team was able to confirm previous results showing high levels of Denisovan ancestry in the region.

Une réplique du crâne Homo erectus Sangiran 17 trouvé à Java, en Indonésie Il n’y a aucun signe que les humains modernes se croisent avec d’anciennes lignées humaines, telles que H erectus, de l’île d’Asie du Sud-Est Crédit: Photo provided by the administrators of the Natural History Museum

Auteur principal et associé de recherche ARC de l’Université d’Adélaïde Dr João Teixeira, said: «Unlike our other cousins, Neanderthals, qui ont un vaste registre fossile en Europe, Denisovans are known almost only from DNA records. The only physical evidence for Denisovan's existence was a finger bone and a few other fragments found in a cave in Siberia and, more recently, a piece of jawbone found on the Tibetan plateau.”

«We know from our own genetic records that the Denisovans mingled with modern humans who came from Africa ago. 50 000 at 60 000 years both in Asia, et alors que les humains modernes traversaient l’île d’Asie du Sud-Est pour se rendre en Australie Les niveaux d’ADN de Denisovan dans les populations contemporaines indiquent qu’un métissage significatif s’est produit dans l’île d’Asie du Sud-Est Le mystère demeure alors, why haven't we found their fossils alongside other ancient humans in the area? Do we need to re-examine the existing fossil record to consider other possibilities? »

The co-author, le professeur Chris Stringer, du Natural History Museum, added: «While the known fossils of Homo erectus, Homo floresiensis and Homo luzonensis may seem to be in the right place and at the right time to represent the mysterious 'Southern Denisovans', leur les ancêtres se trouvaient probablement dans l’île d’Asie du Sud-Est il y a au moins 700000 ans Ce qui signifie que leurs lignées sont trop anciennes pour représenter les Denisoviens qui, by their DNA, were more closely related to Neanderthals and modern humans.”

The co-author, Professor Kris Helgen, chief scientist and director of the Australian Museum Research Institute, said: «These analyzes provide an important window into human evolution in a fascinating region and demonstrate the need for further archaeological research in the region between mainland Asia and Australia.”

Le professeur Helgen a ajouté: «This research also sheds light on a model of survival« megafaunal »which coincides with known areas of premodern human occupation in this part of the world. Large animals that survive in the area today include the Komodo dragon, and the Birus (a pig with remarkable overturned tusks) and the Tamaraw and Anoas (small wild buffaloes). Cela suggère qu’une exposition à long terme à la pression de la chasse par des humains anciens aurait pu faciliter la survie de l’espèce mégafaunale lors de contacts ultérieurs avec les humains modernes. Areas without documented premodern human occurrence, like Australia and New Guinea, have seen the complete extinction of land animals larger than humans during the 50000 last years.”

Dr Teixeira a déclaré: «La recherche corrobore des études antérieures selon lesquelles les Denisoviens se trouvaient sur une île d’Asie du Sud-Est et que les humains modernes ne se sont pas croisés avec des groupes humains plus divergents dans la région. This opens up two equally exciting possibilities: either a major discovery is in progress, or we need to reassess the current fossil record of the Southeast Asian island.”

Reference: «L’ascendance denisovienne répandue dans l’île d’Asie du Sud-Est, mais aucune preuve d’un mélange hominin super-archaïque substantiel» par João C Teixeira, Guy S Jacobs, Chris Stringer, Jonathan Tuke, Georgi Hudjashov, Gludhug A Purnomo, Herawati Sudoyo, Murray P Cox, Raymond Tobler, Chris S M Turney, Alan Cooper et Kristofer M Helgen, 22 mars 2021, Nature Ecology & EvolutionDOI: 101038 / s41559-021-01408-0

SciTechDaily: Home of the best scientific and technological news since 1998 Keep up to date with the latest science news via email or social media

Researchers using NASA's upcoming James Webb Space Telescope will map and model the nucleus of the nearby galaxy Centaurus A As technology has improved over the course of the…

Denisovan, Neanderthal, Homme Flores, Homme droit, Homo luzonensis, Homo, Évolution humaine, Hominini

News – FR – Nouvelle preuve ADN à la recherche des mystérieux Denisovans

Source: https://scitechdaily.com/new-dna-evidence-in-search-for-the-mysterious-denisovans/

Building on its expertise in the areas of digital, technologies and processes , CSS Engineering you in your most ambitious transformation projects and helps you bring out new ideas, new offers, new modes of collaboration, new ways of producing and selling.

CSS Engineering is involved in projects each customer as if it were his own. We believe a consulting company should be more than an advisor. We put ourselves in the place of our customers, to align we incentives to their goals, and collaborate to unlock the full potential their business. This establishes deep relationships and enjoyable.

Our services:

  1. Create professional websites
  2. Hosting high performance and unlimited
  3. Sale and video surveillance cameras installation
  4. Sale and Installation of security system and alarm
  5. E-Marketing

All our achievements here https://www.css-engineering.com/en/works/