ريتشارد دوكنز's Blog, page 402

Random Chance: A Primary Driver of Cancer Mutations?

By Carl Engelking

Whether we like to or not, we’re all gamblers.

Every waking moment, countless stem cells inside our bodies are dividing in order to replace worn out biological machinery. But every time these perfectly healthy cells divide, roughly three mistakes occur in the genetic code—no one’s perfect. These mutations, though unpredictable, are typically benign, but sometimes this molecular game of Roulette takes an unlucky turn.

“Most of the time these mutations don’t do any harm; they’re in junk DNA, or unimportant places,” says Johns Hopkins cancer researcher Bert Vogelstein. “That’s the usual situation, and that’s good luck. But occasionally they occur in a cancer driver gene, and that’s bad luck.”

Today, there’s little doubt that mutations cause cancer, but there’s less consensus regarding the primary instigators of those mutations.

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How to hunt for a black hole with a telescope the size of Earth

By Davide Castelvecchi

Here’s how to catch a black hole. First, spend many years enlisting eight of the top radio observatories across four continents to join forces for an unprecedented hunt. Next, coordinate plans so that those observatories will simultaneously turn their attention to the same patches of sky for several days. Then, collect observations at a scale never before attempted in science — generating 2 petabytes of data each night.

This is the audacious plan for next month’s trial of the Event Horizon Telescope (EHT), a team-up of radio telescopes stationed across the globe to create a virtual observatory nearly as big as Earth. And researchers hope that when they sift through the mountain of data, they will capture the first details ever recorded of the black hole at the centre of the Milky Way, as well as pictures of a much larger one in the more distant galaxy M87.

The reason this effort takes so much astronomical firepower is that these black holes are so far from Earth that they should appear about as big as a bagel on the surface of the Moon, requiring a resolution more than 1,000 times better than that of the Hubble Space Telescope. But even if researchers can nab just a few, blurry pixels, that could have a big impact on fundamental physics, astrophysics and cosmology. The EHT aims to close in on each black hole’s event horizon, the surface beyond which gravity is so strong that nothing that crosses it can ever climb back out. By capturing images of what happens outside this zone, scientists will be able to put Einstein’s general theory of relativity to one of its most stringent tests so far. The images could also help to explain how some supermassive black holes produce spectacularly energetic jets and rule over their respective galaxies and beyond.

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Pakistani police prevent clerics’ rally against blasphemy

By KATHY GANNON, ASSOCIATED PRESS

Pakistani police blocked a rally on Friday in Islamabad by clerics seeking to press their calls for the death of social media activists accused of insulting Islam — an offense punishable by death in this Islamic country.

Hundreds of security forces sealed off and surrounded the Red Mosque, long seen as a refuge for Islamic militants in the Pakistani capital, and the home of a religious leader, Maulana Abdul Aziz, preventing his followers from staging the gathering.

The clerics vowed to try again next week, having already launched blasphemy charges in the Islamabad High Court against five bloggers, who were held for nearly three weeks in January.

The bloggers — who went missing but were later returned unhurt to their families — have accused Pakistan’s intelligence agency of orchestrating their disappearance because of their criticism of the military and intelligence agencies.

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A New Origin Story for Dogs

By Ed Yong

Tens of thousands of years ago, before the internet, before the Industrial Revolution, before literature and mathematics, bronze and iron, before the advent of agriculture, early humans formed an unlikely partnership with another animal—the grey wolf. The fates of our two species became braided together. The wolves changed in body and temperament. Their skulls, teeth, and paws shrank. Their ears flopped. They gained a docile disposition, becoming both less frightening and less fearful. They learned to read the complex expressions that ripple across human faces. They turned into dogs.

Today, dogs are such familiar parts of our lives—our reputed best friends and subject of many a meme—that it’s easy to take them, and what they represent, for granted. Dogs were the first domesticated animals, and their barks heralded the Anthropocene. We raised puppies well before we raised kittens or chickens; before we herded cows, goats, pigs, and sheep; before we planted rice, wheat, barley, and corn; before we remade the world.

“Remove domestication from the human species, and there’s probably a couple of million of us on the planet, max,” says archaeologist and geneticist Greger Larson. “Instead, what do we have? Seven billion people, climate change, travel, innovation and everything. Domestication has influenced the entire earth. And dogs were the first.” For most of human history, “we’re not dissimilar to any other wild primate. We’re manipulating our environments, but not on a scale bigger than, say, a herd of African elephants. And then, we go into partnership with this group of wolves. They altered our relationship with the natural world.”

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Dinosaur crater’s clue to origin of life

By Paul Rincon

The crater made by the asteroid that killed off the dinosaurs is revealing clues to the origins of life on Earth.

Scientists have drilled into the 200km-wide Chicxulub crater now buried under the Gulf of Mexico.

They say its rocks show evidence of having been home to a large “hydrothermal system”, where hot fluids flowed through cracks and fissures.

Similar systems, generated by impacts on the early Earth, could have helped kickstart the first lifeforms.

The hydrothermal system at Chicxulub may have been active for two million years or more, the scientists say.

Dr David Kring, from the Lunar and Planetary Institute in Houston, is one of the researchers who discovered and reported the crater’s location.

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Dinosaur family tree poised for colossal shake-up

By Sid Perkins

The longstanding division of dinosaurs into ‘bird-hipped’ species including Stegosaurus and their ‘lizard-hipped’ counterparts such as Brachiosaurus and Tyrannosaurus rex may no longer be valid, a study published on 22 March in Nature contends1. Among the other proposed changes to the dinosaur family tree, the long-necked herbivorous and often gargantuan sauropods such as Brachiosaurus are no longer as closely related to bipedal, meat-eating theropods such as T. rex as they were under previous schemes.

“This is a textbook changer — if it continues to pan out,” says Thomas Holtz, a vertebrate palaeontologist at the University of Maryland in College Park. “It’s only one analysis, but it’s a thorough one.”

The new study assesses kinship among 74 dinosaur species that span the family tree, on the basis of similarities or differences in more than 450 anatomical features, says Matthew Baron, a vertebrate palaeontologist at the University of Cambridge, UK, who led the study.

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The endangered listing for the rusty patched bumblebee is finally given wings

By Darryl Fears

The rusty patched bumblebee’s path to the endangered list was as up and down as the way it flies.

After a years-long run-up to a determination early this year that it was eligible for the list, and a month-long delay for a newly required review by the Trump administration, the rusty patched on Tuesday became the first bumblebee — and the first bee overall in the continental United States — to be listed under the Endangered Species Act.

As a result, the Natural Resources Defense Council said it could pull a lawsuit filed last month to challenge the delay. That suit could be replaced by another from a coalition of oil, housing developers, farm and energy lobbies that petitioned the Interior Department for a year-long delay in implementing the bee’s status.

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We Might Soon Resurrect Extinct Species. Is It Worth the Cost?

By STEPH YIN

With enough determination, money and smarts, scientists just might revive the woolly mammoth, or some version of it, by splicing genes from ancient mammoths into Asian elephant DNA. The ultimate dream is to generate a sustainable population of mammoths that can once again roam the tundra.

But here’s a sad irony to ponder: What if that dream came at the expense of today’s Asian and African elephants, whose numbers are quickly dwindling because of habitat loss and poaching?

“In 50 years, we might not have those elephants,” said Joseph Bennett, an assistant professor and conservation researcher at Carleton University in Ontario. Dr. Bennett has spent his career asking hard questions about conservation priorities. With only so much funding to go around, deciding which species to save can be a game of triage.

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Faith-healing bill dies in Idaho Senate

By Associated Press

BOISE, Idaho (AP) — BOISE, Idaho (AP) – The Idaho Senate has spiked a proposal seeking to tweak the state’s laws allowing families to cite religious reasons for medical decisions without fear of being charged with neglect or abuse.

The proposal would have only amended Idaho’s civil laws to make it easier for judges to get involved in faith-healing cases. The bill did not change the state’s religious exemption regarding criminal charges, which is considered the most contentious part of the religious waiver.

However, despite the proposal being pitched as a compromise, criticism among lawmakers ranged from those who thought the bill didn’t change enough while others thought the bill went too far.

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This May Be Our Best Idea of What a Dinosaur Really Looked Like

By Jason Bittel

Picture a red-headed woodpecker crossed with a tiny velociraptor, and you have a good mental image of Anchiornis, a foot-high dinosaur that hails from the Late Jurassic.

That’s the conclusion of scientists who examined nine specimens of this ancient animal, lighting up its previously invisible soft tissues with high-powered lasers so they could get an even better idea of the dinosaur’s true dimensions.

The study shows that Anchiornis was remarkably bird-like, with drumstick-shaped legs and long forearms connected by a layer of skin called the patagium. It also had a slender tail and scaly footpads reminiscent of those on a chicken.

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