Hundreds of fossils uncovered in southern China's province of Yunnan reveal that at least some of the life-forms scientists had thought arose in the Cambrian period were alive and thriving millions of years earlier, in an era known as the Ediacaran period.
Four protrusions appear to be arranged in pairs, each consisting of two connected branches surrounding a central depression. We really don't understand what any of these features represent anatomically.
The new work was less notable for showing that we had found these bases in Ryugu than for solving a previous mystery: earlier studies had failed to detect them there, despite their presence in many other asteroid samples.
Colossal Biosciences, valued at $10.2bn after raising hundreds of millions of dollars in funding from investors including celebrities spanning from Tiger Woods to Paris Hilton, has provoked a stampede of acclaim as well as denunciation after announcing last year it had made the dire wolf, a species lost from the world for more than 10,000 years, de-extinct via the birth of three new pups.
Although there are many amber stones containing a single creature, there are fewer that include two or more, as is the case with a pair of mosquitoes trapped in amber 130 million years ago which tell us that, back then, males also sucked blood. Even more extraordinary is when several organisms can be seen interacting, either eating the other, acting as a parasite, or cooperating.
Marine fossils have been discovered on mountain ranges around the world, including the Himalayas, Andes and Rocky Mountains, which scientists say were once covered by ancient seas before being pushed upward as continents collided and mountains formed.
For example, reader David Erickson had this on his mind: If there were aliens 66 million light-years from Earth, how big a telescope would they need to see dinosaurs? Ha! I love this question. I've thought of it myself but never worked out the mathexcept to think, Probably pretty big, which turns out to dramatically underestimate the actual answer.
At first glance, it looked like Wooller and his colleagues might have found evidence that mammoths lived in central Alaska just 2,000 years ago. But ancient DNA revealed that two "mammoth" bones actually belonged to a North Pacific right whale and a minke whale-which raised a whole new set of questions. The team's hunt for Alaska's last mammoth had turned into an epic case of mistaken identity, starring two whale species and a mid-century fossil hunter.
Eukaryotes drastically differ from archaea and bacteria (collectively, prokaryotes) by the complex organization of eukaryotic cells. The signature features of this organizational complexity include the eponymous nucleus, the endomembrane system, the elaborate cytoskeleton and the energy-converting mitochondrion, which evolved from an alphaproteobacterial endosymbiont9. Thus, the last eukaryotic common ancestor (LECA) probably already possessed mitochondria along with the other signatures of the eukaryotic cellular organization.
Mold is a perennial scourge in museums that can disfigure and destroy art and artifacts. To keep this microbial foe in check, institutions follow protocols designed to deter the familiar fungi that thrive in humid settings. But it seems a new front has opened in this long-standing battle. I'd recently heard rumblings that curators in my then home base of Denmark have been wrestling with perplexing infestations that seem to defy the normal rules of engagement.
Wooden objects carrying the marks of carving and use could be the oldest wooden tools ever found. Researchers dated the artefacts, found in what is now Greece, to 430,000 years ago - and suggest they might have been made by early Neanderthals or their ancestors, Homo heidelbergensis. A separate study describes 480,000-old flint-knapping tools made from antler and elephant bone, from what is now the United Kingdom.
New research published today in Nature dates the boneschipped out from a cave called Grotte a Hominides and nearby it over decadesto about 773,000 years ago, during the era of the last common ancestor of Homo sapiens, Homo neanderthalensis and Denisovans (a group of humans that ranged across Asia and that does not have an agreed-upon species name). We can say that the shared ancestry between these three species is perhaps in Grotte a Hominides in Casablanca, says study co-author Abderrahim Mohib, a prehistorian at the National Institute of Archaeology and Heritage Sciences in Rabat, Morocco.
We have little physical evidence of these interactions turning violent, however, because burials were rare and carnivores were more likely to finish off their prey. That's why the embellished burial site of a 15-year-old from 27,000 years ago is an important window into the past: the teenager's bones indicate he was mauled by a bear. The finding represents some of the first evidence of its kind.
Which animals came first? For more than a century, most evidence suggested that sponges, immobile filter-feeders that lack muscles, neurons and other specialized tissues, were the first animal lineages to emerge. Then, in 2008, a genomic study pointed to a head-scratching rival: dazzling, translucent predators called comb jellies, or ctenophores, with nerves, muscles and other sophisticated features. That single study ignited a debate that has raged for nearly 20 years, sparking fierce arguments about how complexity evolved in animals.
