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.
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.
We think that in this early deuterostome, the median eye contained both ciliary and rhabdomeric cells. As a result, both cellular lineages were incorporated into a single, ancient, cyclopean eye, which later evolved into the vertebrate eyes.
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.
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.
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.
The lava heron also has a much thicker bill than other closely related herons - an adaptation linked to feeding among sharp volcanic rocks and hard-shelled prey. "What we learned was something that hadn't been reported before," Mendales said. The discovery underscores how much remains unknown, even in iconic places like the Galápagos, said John Dumbacher, the Academy's curator of birds and mammals and Mendales' thesis adviser.
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.
In a sudden turn of events last Wednesday the U.S. Food and Drug Administration agreed to review Moderna's new mRNA flu vaccine, according to the company. The announcement came roughly a week after Moderna revealed that the FDA had rejected its application. The company said the agency originally called the plan for the vaccine's phase 3 trials acceptable, But its position changed after top FDA official Vinay Prasad overruled the agency's reviewers, according to STAT.
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.
