La plus grande météorite martienne jamais retrouvée, revendiquée par le Niger, est mise en vente à New York.

Des chercheurs autochtones développent des outils spécifiques aux besoins de leurs nations.

Il était le commandant de la célèbre mission lunaire Apollo 13, qui avait échappé de peu à la catastrophe.

The announcement comes a week after the National Transportation Safety Board grilled aviation officials about safety gaps in the airspace near the capital.

© Kenny Holston/The New York Times

Si l’appareil se rend comme prévu dans l’espace, il s’agira d’une première dans l’histoire de la province.

La pluie de météores atteindra son paroxysme dans la nuit du 12 au 13 août.

Certains survivants ayant peu de moyens seraient revenus s’installer dans la zone dévastée.

Scientists have discovered million-year-old artifacts made by a mysterious group of early humans on the Indonesian island of Sulawesi, according to a breakthrough study published on Wednesday in Nature. 

The extraordinary find pushes the archaeological record of Sulawesi back by about 800,000 years, and confirms that hominins, the broader family to which humans belong, crossed treacherous ocean passages to reach the island, where they crafted simple tools.

The tool-makers may have been related to a group of archaic humans—nicknamed “hobbits” for their short stature—that lived on nearby Flores Island. But while the hobbits left behind skeletal remains, no fossils from the Sulawesi group have been unearthed. The tools, found at a site called Calio in South Sulawesi, are the only record of their existence for now.

“The discovery of these ancient stone tools at Calio is another important piece of the puzzle in our understanding of the movements of early hominins from the edge of the Asian landmass into the isolated zone of islands known as Wallacea,” said Adam Brumm, a professor of archaeology at Griffith University and a co-author of the new study, in an email. 

“A major question remaining is the identity of the archaic humans of Sulawesi,” he added, noting that they might be Homo erectus, or descendents of this influential early human species that migrated from Africa to Asia. ”But until we have their fossils, who they were will remain a mystery.”

The discovery was made by Budianto “Budi” Hakim, an Indonesian archaeologist who has spent decades searching for traces of archaic humans in Sulawesi. Hakim spotted one of the artifacts while scouring the region’s sandstone outcrops, prompting an excavation that unearthed a total of seven flaked tools crafted from chert rock. The remains of extinct elephants and pigs were also found in the sedimentary layers at the site, hinting at an ancient origin.

The team used two independent methods to date the tools, both of which placed their age at a minimum of 1.04 million years old, making the artifacts the earliest evidence for hominin occupation of Sulawesi by far.

“Budi has been searching for this evidence for much of his life, so it is very exciting indeed,” said Brumm. “But it is not so surprising that we now have evidence for hominins on Sulawesi by one million years ago; we have long suspected that there had been a very deep history of human occupation of this island based on the discovery (in 2010) of stone tools on Flores to the south that date to at least a million years ago. Sulawesi was probably where the first hominins to set foot on Flores actually came from, so it made sense to us that the human presence on Sulawesi would go back at least as far as a million years, if not considerably earlier.” 

“And personally, it did not surprise me that Budi unearthed this new find,” he continued. “He is a renowned figure in Indonesian archaeology and undoubtedly has the ‘golden touch.’”

The tools are sharp-edged flakes that were probably cut from larger rocks obtained from a nearby river channel. Like many tools made by hominins across time and regions, they would have been useful for cutting and scraping materials, though their exact purpose is unknown.  

The tools “can’t tell us very much about the behaviour or cognitive capacities of these early humans, other than that they were tool-makers who clearly understood how to choose stones with suitable properties and to fracture them in a controlled way to produce a supply of usable tools,” explained Brumm. “Over the past 2.5 million years, many different hominin species (including our own, Homo sapiens) have made stone tools that are essentially indistinguishable from the Sulawesi tools.”

In addition to their mysterious identity, it is unclear how these early humans crossed ocean waters to reach these island shores, given that the shortest distance between the Asian mainland and Sulawesi would have been 30 miles, at minimum.

“This is too far to swim (in any case the ocean currents are too strong),” Brumm explained. “It is also very unlikely these archaic hominins had the cognitive ability to develop watercraft that were capable of making sea voyages, or indeed of the advanced planning required to gather resources and set sail over the horizon to an unseen land.” 

“Most likely, they crossed to Sulawesi from the Asian mainland in the same way rodents and monkeys are suspected to have done; that is, by accident, perhaps as castaways on natural ‘rafts’ of floating vegetation,” he concluded.

It’s incredible to imagine these early humans getting caught up in tides or currents, perhaps stranded at sea for days, only to serendipitously wash up on a vast island that would become home to untold generations. Hakim, Brumm, and their colleagues hope to find more evidence of this long-lost population in the coming years, but for now, the stone tools offer a rare window into the lives of these accidental seafarers and their descendants.

The Sun powers almost all life on Earth, but chemosynthetic life is the fascinating exception. These organisms find fuel in chemical reactions, allowing them to flourish in places where the Sun doesn’t shine—like the deep sea.

Now, scientists have discovered chemosynthetic animals, such as foot-long tubeworms and mollusks, nearly six miles beneath the ocean surface, deeper than these ecosystems have ever been observed before, according to a study published on Wednesday in Nature. 

Researchers witnessed the hotspots of chemosynthetic life in person during crewed dives in the Fendouzhe submersible, which descended nearly 31,000 feet to the ocean’s deepest regions, known as hadal trenches, in the North Pacific.

The legislation, led by Senator Ted Cruz, the Republican chairman of a panel that oversees air travel, has a number of high-profile supporters — but no Democrats, yet.

© Kenny Holston/The New York Times

Thousands of scientific papers have used data collected by users of the platform iNaturalist, according to new research.

New observations fail to confirm signs of life in the atmosphere of the distant planet K2-18b. They also raise questions about what it will take to detect biology light-years away.

© N. Madhusudhan/University of Cambridge, via Agence France-Presse — Getty Images

The discovery, in a bizarre animal not closely related to birds, could change how scientists think about the origin of feathers.

A new global atlas of underground fungi suggests that some surprising biodiversity hot spots lie hidden beneath our feet.

© Tomas Munita for The New York Times

L’administration Trump a pris une nouvelle mesure lundi pour rendre plus difficile la recherche d’évaluations scientifiques majeures, légalement obligatoires, sur les dangers des changements climatiques pour le pays et sa population.
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Le taux de cholestérol est dans le sang. On retrouve deux types principaux de cholestérol sanguin : celui de haute densité, ou HDL, et celui de faible densité, ou LDL.
Le cholestérol LDL est celui qu’on dit « mauvais » : s’il est présent en trop grande quantité, il peut former des plaques et des dépôts gras sur les parois des artères, et ainsi empêcher le sang de circuler jusqu’au cœur et au cerveau.
Le HDL, en comparaison, est « bon », car il permet d’éliminer l’excès de cholestérol que l’on retrouve dans le corps.
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Nous avons construit depuis dix mille ans, un monde d’abondance de ressources, un écosystème stable, qui nous a poussé à optimiser et à performer. Le culte d...
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