Browsed by
Category: Evolution

A mysterious crater’s age may add clues to the dinosaur extinction

A mysterious crater’s age may add clues to the dinosaur extinction

The New York Times reports: Some 65 million years ago, a rock from outer space slammed into Earth, wreaking havoc on life in its wake and leaving a large crater on our planet’s surface. No, it’s not the one you’re thinking of. Boltysh crater, a 15-mile-wide formation in central Ukraine, may not be as famous as the Chicxulub crater under the Yucatán Peninsula in Mexico, which is directly implicated in the death of the dinosaurs and many other species about…

Read More Read More

The day the dinosaurs died

The day the dinosaurs died

Douglas Preston writes: If, on a certain evening about sixty-­six million years ago, you had stood somewhere in North America and looked up at the sky, you would have soon made out what appeared to be a star. If you watched for an hour or two, the star would have seemed to grow in brightness, although it barely moved. That’s because it was not a star but an asteroid, and it was headed directly for Earth at about forty-five thousand…

Read More Read More

No one knows how often DNA jumps between animal species

No one knows how often DNA jumps between animal species

Christie Wilcox writes: To survive in the frigid ocean waters around the Arctic and Antarctica, marine life evolved many defenses against the lethal cold. One common adaptation is the ability to make antifreezing proteins (AFPs) that prevent ice crystals from growing in blood, tissues and cells. It’s a solution that has evolved repeatedly and independently, not just in fish but in plants, fungi and bacteria. It isn’t surprising, then, that herrings and smelts, two groups of fish that commonly roam…

Read More Read More

Is a revolution brewing in evolutionary theory?

Is a revolution brewing in evolutionary theory?

Kevin Laland writes: When researchers at Emory University in Atlanta trained mice to fear the smell of almonds (by pairing it with electric shocks), they found, to their consternation, that both the children and grandchildren of these mice were spontaneously afraid of the same smell. That is not supposed to happen. Generations of schoolchildren have been taught that the inheritance of acquired characteristics is impossible. A mouse should not be born with something its parents have learned during their lifetimes,…

Read More Read More

Life deep underground and inside other worlds

Life deep underground and inside other worlds

Jordana Cepelewicz writes: Scientists poke and prod at the fringes of habitability in pursuit of life’s limits. To that end, they have tunneled kilometers below Earth’s surface, drilling outward from the bottoms of mine shafts and sinking boreholes deep into ocean sediments. To their surprise, “life was everywhere that we looked,” said Tori Hoehler, a chemist and astrobiologist at NASA’s Ames Research Center. And it was present in staggering quantities: By various estimates, the inhabited subsurface realm has twice the…

Read More Read More

The ‘dark matter’ inside your gut

The ‘dark matter’ inside your gut

Jonathan Jarry writes: There is a kind of dark matter inside our intestinal tract. “Dark matter” is the phrase coined for the matter that is implied to be present in the universe based on physicists’ calculations but that cannot be seen yet. Scientists who study tiny living things are facing their own type of dark matter: invisible microbes that are indirectly detected. They call it “microbial dark matter.” Much has been written about the bacteria that live inside our gut….

Read More Read More

Sleep evolved before brains. Hydras are living proof

Sleep evolved before brains. Hydras are living proof

Veronique Greenwood writes: The hydra is a simple creature. Less than half an inch long, its tubular body has a foot at one end and a mouth at the other. The foot clings to a surface underwater — a plant or a rock, perhaps — and the mouth, ringed with tentacles, ensnares passing water fleas. It does not have a brain, or even much of a nervous system. And yet, new research shows, it sleeps. Studies by a team in…

Read More Read More

Neanderthals carb loaded, helping grow their big brains

Neanderthals carb loaded, helping grow their big brains

Science reports: Here’s another blow to the popular image of Neanderthals as brutish meat eaters: A new study of bacteria collected from Neanderthal teeth shows that our close cousins ate so many roots, nuts, or other starchy foods that they dramatically altered the type of bacteria in their mouths. The finding suggests our ancestors had adapted to eating lots of starch by at least 600,000 years ago—about the same time as they needed more sugars to fuel a big expansion…

Read More Read More

Is music what makes us human?

Is music what makes us human?

Kevin Berger writes: In the past two years, the debate over whether music is universal, or even whether that debate has merit, has raged like a battle of the bands among scientists. The stage has expanded from musicology to evolutionary biology to cultural anthropology. This summer, in the journal Behavioral and Brain Sciences, more than 100 scholars sound off on evolution and universality of music. I love the din. The academic discord gives way to a symphony of insights into…

Read More Read More

One incredible ocean crossing may have made human evolution possible

One incredible ocean crossing may have made human evolution possible

Yasni/Shutterstock By Nicholas R. Longrich, University of Bath Humans evolved in Africa, along with chimpanzees, gorillas and monkeys. But primates themselves appear to have evolved elsewhere – likely in Asia – before colonising Africa. At the time, around 50 million years ago, Africa was an island isolated from the rest of the world by ocean – so how did primates get there? A land bridge is the obvious explanation, but the geological evidence currently argues against it. Instead, we’re left…

Read More Read More

Natural GM: How plants and animals steal genes from other species to accelerate evolution

Natural GM: How plants and animals steal genes from other species to accelerate evolution

Grassland in Uganda. Luke Dunning, Author provided By Luke Dunning, University of Sheffield Little did biologist Gregor Mendel know that his experiments with sweet peas in a monastery garden in Brno, Czech Republic, would lay the foundations for our understanding of modern genetics and inheritance. His work in the 19th century helped scientists to establish that parents pass their genetic information onto their offspring, and in turn, they pass it on to theirs. Indeed, this premise forms the basis of…

Read More Read More

At any one time, 20,000 Tyrannosaurus rex roamed the Earth, calculation determines

At any one time, 20,000 Tyrannosaurus rex roamed the Earth, calculation determines

Nature reports: Ever wondered how many Tyrannosaurus rex ever roamed the Earth? The answer is 2.5 billion over the two million or so years for which the species existed, according to a calculation published today in Science1. The figure has allowed researchers to estimate just how exceedingly rare it is for animals to fossilize. Palaeontologists led by Charles Marshall at the University of California, Berkeley, used a method employed by ecologists studying contemporary creatures to estimate the population density of…

Read More Read More

How bipedalism led humans down a strange evolutionary path

How bipedalism led humans down a strange evolutionary path

Riley Black writes: No other animal moves the way we do. That’s awfully strange. Even among other two-legged species, none amble about with a straight back and a gait that, technically, is just a form of controlled falling. Our bipedalism doesn’t just set us apart, paleoanthropologist Jeremy DeSilva posits; it’s what makes us human. There’s no shortage of books that propose this or that feature — tool use or self-awareness, for example — as the very definition of humankind. But much of our supposed…

Read More Read More

I have come to bury Ayn Rand

I have come to bury Ayn Rand

David Sloan Wilson writes: My father, Sloan Wilson, wrote novels that would help define 1950s America. I loved and admired him, but the prospect of following in the footsteps of The Man in the Gray Flannel Suit and A Summer Place was like being expected to climb Mount Everest. My love of nature provided an alternative path. I would become an ecologist, spending my days researching plants and animals, which fascinated me since the summers I spent as a boy…

Read More Read More

New data helps clarify how plate tectonics drove the evolution of complex life

New data helps clarify how plate tectonics drove the evolution of complex life

Howard Lee writes: In 2016, the geochemists Jonas Tusch and Carsten Münker hammered a thousand pounds of rock from the Australian Outback and airfreighted it home to Cologne, Germany. Five years of sawing, crushing, dissolving and analyzing later, they have coaxed from those rocks a secret hidden for eons: the era when plate tectonics began. Earth’s fractured carapace of rigid, interlocking plates is unique in the solar system. Scientists increasingly connect it to our planet’s other special features, such as…

Read More Read More

Nature knows how to avoid network collapse

Nature knows how to avoid network collapse

Ruth DeFries writes: Sometime in the first billion years of the planet’s 4.5-billion-year history, a cell emerged in a primordial stew of chemicals brewing in liquid water. At that moment, the predictable chemistry and physics of the early Earth gave way to seething, roiling complexity. Primitive life thrived in the deep sea, where underwater volcanoes vented heat and spilled a cocktail of chemicals into seawater. Once life was underway, the course of the planet and the life it supported became…

Read More Read More