In the murky darkness, blue and green blobs are dancing. Sometimes they keep decorous distances from each other, but other times they go cheek to cheek — and when that happens, other colors flare. The video, reported last year, is fuzzy and a few seconds long, but it wowed the scientists who saw it. For the first time, they were witnessing details of an early step — long unseen, just cleverly inferred — in a central event in biology: the act of turning on a gene. Those blue an ...read more

Narwhals, the unicorns of the sea, have survived for a million years with low genetic diversity — a trait that usually suggests a species is close to extinction. But a recent survey found narwhals number in the hundreds of thousands, countering the assumption that lots of gene variants within a population are necessary for survival. "There's this notion that in order to survive and be resilient to changes, you need to have high genetic diversity, but then you have this species t ...read more

In the largest-ever ancient DNA study of its kind, researchers have pieced together the history of the horse: It's an epic saga sprawling across continents and 5,000 years of evolution and domestication, and yes, it has plot twists. Among the finds: researchers uncovered two lost lineages of the animal on opposite ends of Eurasia and determined that the modern horse is very different than even its recent ancestors, thanks in part to geopolitics. The scope of the study included 278 sa ...read more

Lead water pipes have been a fixture of modern civilization for more than two thousand years.  Ancient Romans channeled water into homes and bathhouses through lead piping. In fact, the Latin word for lead, plumbum, is where we get the English word “plumbing.” Yet we have also long recognized that lead can have a serious impact on our health. Vitrivius, who lived during the first century BCE, wrote at length about the physical harm caused by lead exposure, concluding t ...read more

The European Space Agency's Gaia spacecraft is on a mission to map a billion stars. But as it stares out into space, it also spies a lot of closer objects. The newly released image above shows the orbits of 14,000 asteroids that it mapped during its first two years of observing. Most of those objects were known about from previous surveys. But three objects are new, those ones are picked out in gray in Gaia’s image. The few dozen yellow tracks show asteroids that are considered near-Earth ...read more

In 2010, a Japanese mission called Hayabusa returned to Earth from a seven-year space journey. It brought back not only images and data from its adventure, but also actual samples, small grains of rock from its target, the asteroid Itokawa. Just a handful of space missions have ever returned to Earth at all, let alone brought back pieces of their destinations. So Hayabusa’s samples are highly prized, and have been studied by many teams across the world. Now, researchers from Ari ...read more

A largely complete, roughly 300,000-year-old skull from southeastern China appears to be the latest evidence challenging the dominant model of human evolution. The Hualongdong skull's unique combination of features make the fossil a tantalizing clue to East Asia's diverse hominin history. Researchers excavating a collapsed cave site unearthed the skull, formally known as Hualongdong 6 (HLD 6), along with additional partial fossils of archaic humans and animals, plus assorted sto ...read more

On the mountainous Tibetan Plateau, small groups of nomadic herders still make a living two miles or more above sea level. Most of us would be poorly-equipped to deal with that altitude for long periods of time, but the Tibetans there have unique genetic adaptations that let their bodies function in the thin air. Mysteriously, those genes seem to come from another species of human, the Denisovans, a little-understood group of hominins who died out tens of thousands of years ago. ...read more

The Earth has always been in the path of rocks from space. When the solar system was forming, the early Earth was pelted with rocks so frequently that it left the surface molten. In fact, the creation of the Moon was caused by a massive impact of a "rock", albeit a Mars-sized rock. These days, there are many fewer impacts (thankfully) but the threat still remains that an asteroid we might not even know about yet could strike the planet. This week, as part of the 2019 Planetary Defense Confer ...read more

We've reached another "will they or won't they?" cliffhanger in the long-running soap opera, When Will Humans Return to the Moon? Last May, NASA administrator Jim Bridenstine promised that a crew would be landing there by 2028. "To many, this may sound similar to our previous attempts to get to the Moon," he admitted. "However, times have changed. This will not be Lucy and the football again." A month ago, Vice President Pence added a big plot twist, now declaring that "it is the stated pol ...read more