Your gut bacteria predates appearance of humans, genetic study finds

The Guardian reports: The evolutionary history of the bacteria in your guts predates the appearance of humans, and mirrors that of our great ape relatives, according to a genetic study.

The research suggests that microbes in our ancestors’ intestines split into new evolutionary lineages in parallel with splits in the ape family tree.

This came as a surprise to scientists, who had thought that most of our gut bacteria came from our surroundings – what we eat, where we live, even what kind of medicine we take. The new research suggests that evolutionary history is much more important than previously thought.

“When there were no humans or gorillas, just ancestral African apes, they harboured gut bacteria. Then the apes split into different branches, and there was also a parallel divergence of different gut bacteria,” said Prof Andrew Moeller of the University of California, Berkeley who led the study, published in Science. This happened when gorillas separated somewhere between 10-15 million years ago, and again when humans split from chimps and bonobos 5 million years ago. [Continue reading…]

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Biodiversity is below safe levels across more than half of world’s land, say scientists

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The Guardian reports: The variety of animals and plants has fallen to dangerous levels across more than half of the world’s landmass due to humanity destroying habitats to use as farmland, scientists have estimated.

The unchecked loss of biodiversity is akin to playing ecological roulette and will set back efforts to bring people out of poverty in the long term, they warned.

Analysing 1.8m records from 39,123 sites across Earth, the international study found that a measure of the intactness of biodiversity at sites has fallen below a safety limit across 58.1% of the world’s land.

Under a proposal put forward by experts last year, a site losing more than 10% of its biodiversity is considered to have passed a precautionary threshold, beyond which the ecosystem’s ability to function could be compromised.

“It’s worrying that land use has already pushed biodiversity below the level proposed as a safe limit,” said Prof Andy Purvis, of the Natural History Museum, and one of the authors. “Until and unless we can bring biodiversity back up, we’re playing ecological roulette.” [Continue reading…]

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Goats, sheep and cows could challenge dogs for title of ‘man’s best friend’

By Catherine Douglas, Newcastle University

Since the evolution of dogs from wolves tens of thousands of years ago, they have been selectively bred for various roles as guards, hunters, workers and companions. But dogs are not the only animal humans have domesticated, which suggests that although dogs get all the attention, there’s reason to argue other species could also deserve the title of “man’s best friend”.

Anthrozoology, the study of human-animal relationships, has established that dogs demonstrate complex communication with humans. Charles Darwin thought that dogs experienced love, but it was only in 2015 that Japanese scientists demonstrated what we all intuitively knew. Miho Nagasawa and colleagues sprayed the “love hormone” oxytocin up dogs’ noses, measured the loving gaze between dog and human, and then measured the oxytocin levels in the humans’ urine, finding them to be higher. Rest assured, dog owners, that science has verified your bond with your faithful hound.

Horses also show intentional communicative behaviour with humans, and another recent paper published in the Royal Society’s Biology Letters from researchers at Queen Mary University of London has shown that goats also demonstrate an affinity with humans. The experiments tested goats’ intelligence and ability to communicate with humans. What the team found may come as no surprise to anyone who has worked with livestock: goats are highly intelligent, capable of complex communication with humans, and are able to form bonds with us – treating us as potential partners to help in problem-solving situations.

Our attitudes to animals tend to reflect the familiarity we have with them. Dogs score higher in perceived intelligence ratings than cows, for example, yet a study in the 1970s demonstrated that in a test cows could navigate a maze as well as dogs, and only slightly less well than children. The point was made that our perception of an animal’s ability is influenced by how we test them.

[Read more…]

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Learning from nature: Record-efficiency turbine farms are being inspired by sealife

Alex Riley writes: As they drove on featureless dirt roads on the first Tuesday of 2010, John Dabiri, professor of aeronautics and bioengineering at the California Institute of Technology, and his then-student Robert Whittlesey, were inspecting a remote area of land that they hoped to purchase to test new concepts in wind power. They named their site FLOWE for Field Laboratory for Optimized Wind Energy. Situated between gentle knolls covered in sere vegetation, the four-acre parcel in Antelope Valley, California, was once destined to become a mall, but those plans fell through. The land was cheap. And, more importantly, it was windy.

Estimated at 250 trillion Watts, the amount of wind on Earth has the potential to provide more than 20 times our current global energy consumption. Yet, only four countries — Spain, Portugal, Ireland, and Denmark — generate more than 10 percent of their electricity this way. The United States, one of the largest, wealthiest, and windiest of countries, comes in at about 4 percent. There are reasons for that. Wind farm expansion brings with it huge engineering costs, unsightly countryside, loud noises, disruption to military radar, and death of wildlife. Recent estimates blamed turbines for killing 600,000 bats and up to 440,000 birds a year. On June 19, 2014, the American Bird Conservancy filed a lawsuit against the federal government asking it to curtail the impact of wind farms on the dwindling eagle populations. And while standalone horizontal-axis turbines harvest wind energy well, in a group they’re highly profligate. As their propeller-like blades spin, the turbines facing into the wind disrupt free-flowing air, creating a wake of slow-moving, infertile air behind them. [Continue reading…]

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A molecule deep in space could help explain the origins of life

Discover Magazine reports: A peculiar new molecule hovering within a star-forming dust cloud in deep in space could help explain why life on Earth is the way it is.

The cloud, called Sagittarius B2, resides near the center of the Milky Way, and it’s there that researchers from the California Institute of Technology discovered an organic element that displays a key property shared by all life. Propylene oxide is the first element discovered outside of our solar system to exhibit chirality, or the presence of two distinct, mirror-image forms. Many complex molecules have this property, including myriad organic molecules necessary for life. The chemical formula of these two versions is exactly the same, but the structure is flipped.

All life on Earth is composed of chiral molecules, and the versions organisms use, either right- or left-handed, determines fundamental properties of their biology. For example, all living things only use the right-handed form of the sugar ribose to form the backbone of DNA, giving it that the signature twist. You can think of molecular handedness by picturing gloves — hence the “handed terminology”. The gloves, or molecules, may look similar, but you could never put a left-handed glove on your right hand. [Continue reading…]

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RIP Bob Paine, a keystone among ecologists

Ed Yong writes: I’m deeply saddened to learn that Bob Paine, a giant of ecology, passed away yesterday. You may not know his name, but you almost certainly know the ideas that he pioneered.

Back in 1963, Paine began prying ochre starfish off a rocky beach in Washington and hurling them into the sea. After a year, the mussels that the starfish would normally have eaten had overrun the beach, turning a wonderland of limpets, anemones, and barnacles into a monoculture of black gaping shells.

The experiment was ground-breaking. It showed that not all species are equal, and that some — like the starfish—are secret lynchpins of the natural world. Their absence can ripple outwards, triggering the rise and fall of connected species and can even reshape the landscape. For example, when sea otters vanish, the sea urchins they eat transform lush forests of kelp into desolate barrens, dooming the fish, crabs, and other animals that once lived there. Paine called these ripples “trophic cascades”, and he billed the animals behind them — the starfish, otters, and others — as “keystone species”, after the central stone that stops an arch from collapsing. These concepts are so familiar today that we take them for granted, but we didn’t always know about them. We only do because of Paine. [Continue reading…]

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Yes, there have been aliens

Adam Frank writes: Last month astronomers from the Kepler spacecraft team announced the discovery of 1,284 new planets, all orbiting stars outside our solar system. The total number of such “exoplanets” confirmed via Kepler and other methods now stands at more than 3,000.

This represents a revolution in planetary knowledge. A decade or so ago the discovery of even a single new exoplanet was big news. Not anymore. Improvements in astronomical observation technology have moved us from retail to wholesale planet discovery. We now know, for example, that every star in the sky likely hosts at least one planet.

But planets are only the beginning of the story. What everyone wants to know is whether any of these worlds has aliens living on it. Does our newfound knowledge of planets bring us any closer to answering that question?

A little bit, actually, yes. In a paper published in the May issue of the journal Astrobiology, the astronomer Woodruff Sullivan and I show that while we do not know if any advanced extraterrestrial civilizations currently exist in our galaxy, we now have enough information to conclude that they almost certainly existed at some point in cosmic history. [Continue reading…]

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Theophrastus: The unsung hero of Western Science

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Andrea Wulf writes: In 345 B.C.E., two men took a trip that changed the way we make sense of the natural world. Their names were Theophrastus and Aristotle, and they were staying on Lesbos, the Greek island where tens of thousands of Syrian refugees have recently landed.

Theophrastus and Aristotle were two of the greatest thinkers in ancient Greece. They set out to bring order to nature by doing something very unusual for the time: they examined living things and got their hands dirty. They turned away from Plato’s idealism and looked at the real world. Both Aristotle and Theophrastus believed that the study of nature was as important as metaphysics, politics, or mathematics. Nothing was too small or insignificant. “There is something awesome in all natural things.” Aristotle said, “inherent in each of them there is something natural and beautiful.”

Aristotle is the more famous of the two men, but Theophrastus deserves equal bidding in any history of naturalism. Born around 372 B.C.E. in Eresos, a town on the southwestern coast of Lesbos, Theophrastus was 13 years younger than Aristotle. According to Diogenes Laërtius — a biographer who wrote his Eminent Philosophers more than 400 years afterwards but who is the main source for what we know about Theophrastus’ life — Theophrastus was one of Aristotle’s pupils at Plato’s Academy. For many years they worked closely together until Aristotle’s death in 322 B.C.E. when Theophrastus became his successor at the Lyceum school in Athens and inherited his magnificent library. [Continue reading…]

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‘Gene drives’ that tinker with evolution are an unknown risk, researchers say

MIT Technology Review reports: With great power — in this case, a technology that can alter the rules of evolution — comes great responsibility. And since there are “considerable gaps in knowledge” about the possible consequences of releasing this technology, called a gene drive, into natural environments, it is not yet responsible to do so. That’s the major conclusion of a report published today by the National Academies of Science, Engineering, and Medicine.

Gene drives hold immense promise for controlling or eradicating vector-borne diseases like Zika virus and malaria, or in managing agricultural pests or invasive species. But the 200-page report, written by a committee of 16 experts, highlights how ill-equipped we are to assess the environmental and ecological risks of using gene drives. And it provides a glimpse at the challenges they will create for policymakers.

The technology is inspired by natural phenomena through which particular “selfish” genes are passed to offspring at higher rate than is normally allowed by nature in sexually reproducing organisms. There are multiple ways to make gene drives in the lab, but scientists are now using the gene-editing tool known as CRISPR to very rapidly and effectively do the trick. Evidence in mosquitoes, fruit flies, and yeast suggests that this could be used to spread a gene through nearly 100 percent of a population.

The possible ecological effects, intended or not, are far from clear, though. How long will gene drives persist in the environment? What is the chance that an engineered organism could pass the gene drive to an unintended recipient? How might these things affect the whole ecosystem? How much does all this vary depending on the particular organism and ecosystem?

Research on the molecular biology of gene drives has outpaced ecological research on how genes move through populations and between species, the report says, making it impossible to adequately answer these and other thorny questions. Substantially more laboratory research and confined field testing is needed to better grasp the risks. [Continue reading…]

Jim Thomas writes: If there is a prize for the fastest emerging tech controversy of the century the ‘gene drive’ may have just won it. In under eighteen months the sci-fi concept of a ‘mutagenic chain reaction’ that can drive a genetic trait through an entire species (and maybe eradicate that species too) has gone from theory to published proof of principle to massively-shared TED talk (apparently an important step these days) to the subject of a US National Academy of Sciences high profile study – complete with committees, hearings, public inputs and a glossy 216 page report release. Previous technology controversies have taken anywhere from a decade to over a century to reach that level of policy attention. So why were Gene Drives put on the turbo track to science academy report status? One word: leverage.

What a gene drive does is simple: it ensures that a chosen genetic trait will reliably be passed on to the next generation and every generation thereafter. This overcomes normal Mendelian genetics where a trait may be diluted or lost through the generations. The effect is that the engineered trait is driven through an entire population, re-engineering not just single organisms but enforcing the change in every descendant – re-shaping entire species and ecosystems at will.

It’s a perfect case of a very high-leverage technology. Archimedes famously said “Give me a lever long enough and a fulcrum on which to place it, and I shall move the world. ” Gene drive developers are in effect saying “Give me a gene drive and an organism to put it in and I can wipe out species, alter ecosystems and cause large-scale modifications.” Gene drive pioneer Kevin Esvelt calls gene drives “an experiment where if you screw up, it affects the whole world”. [Continue reading…]

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Genes are overrated

Nathaniel Comfort writes: In the Darwinian struggle of scientific ideas, the gene is surely among the select. It has become the foundation of medicine and the basis of vigorous biotechnology and pharmaceutical industries. Media coverage of recent studies touts genes for crime, obesity, intelligence — even the love of bacon. We treat our genes as our identity. Order a home genetic-testing kit from the company 23andMe, and the box arrives proclaiming, “Welcome to you.” Cheerleaders for crispr, the new, revolutionarily simple method of editing genes, foretell designer babies, the end of disease, and perhaps even the transformation of humanity into a new and better species. When we control the gene, its champions promise, we will be the masters of our own destiny.

The gene has now found a fittingly high-profile chronicler in Siddhartha Mukherjee, the oncologist-author of the Pulitzer Prize–winning The Emperor of All Maladies, a history of cancer. The Gene’s dominant traits are historical breadth, clinical compassion, and Mukherjee’s characteristic graceful style. He calls it “an intimate history” because he shares with us his own dawning awareness of heredity and his quest to make meaning of it. The curtain rises on Kolkata, where he has gone to visit Moni, his paternal cousin, who has been diagnosed with schizophrenia. In addition to Moni, two of the author’s uncles were afflicted with “various unravelings of the mind.” Asked for a Bengali term for such inherited illness, Mukherjee’s father replies, “Abheder dosh” — a flaw in identity. Schizophrenia becomes a troubling touchstone throughout the book. But the Indian interludes are tacked onto an otherwise conventional triumphalist account of European-American genetics, written from the winners’ point of view: a history of the emperor of all molecules. [Continue reading…]

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Eagles take down drones

The New York Times reports: Its wings beating against a gathering breeze, the eagle moves gracefully through a cloudy sky, then swoops, talons outstretched, on its prey below.

The target, however, is not another bird but a small drone, and when the eagle connects, there is a metallic clunk. With the device in its grasp, the bird of prey returns to the ground.

At a disused military airfield in the Netherlands, hunting birds like the eagle are being trained to harness their instincts to help combat the security threats stemming from the proliferation of drones.

The birds of prey learn to intercept small, off-the-shelf drones — unmanned aerial vehicles — of the type that can pose risks to aircraft, drop contraband into jails, conduct surveillance or fly dangerously over public events.

The thought of terrorists using drones haunts security officials in Europe and elsewhere, and among those who watched the demonstration at Valkenburg Naval Air Base this month was Mark Wiebes, a detective chief superintendent in the Dutch police.

Mr. Wiebes described the tests as “very promising,” and said that, subject to a final assessment, birds of prey were likely to be deployed soon in the Netherlands, along with other measures to counter drones. The Metropolitan Police Service in London is also considering using trained birds to fight drones. [Continue reading…]

This has been described as a “a low-tech solution for a high-tech problem” but, on the contrary, what it highlights is the fact that in terms of maneuverability, the flying skills of an eagle (and most other flying creatures) are vastly superior to any form of technology.

In this, as in so many other instances, technology crudely imitates nature.

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What the songs of wolves reveal about language

Holly Root-Gutteridge writes: Dialects, or regional differences in the form and use of vocalisations, have been observed in birds, bats, chimpanzees and now an increasingly long list of other species. This has been most beautifully heard in whales, where the songs of humpbacks are transmitted across hundreds of miles, telling a listener which part of the ocean the whale lives in, and tracing its family group by the influences on song formations. The bioacousticians Katharine Payne and Roger Payne first listened to the whales on underwater microphone recordings in the 1960s, and used musical notation to explore the changes that occurred in each male’s song, year on year. Whalesong, heard by humans as long ago as Aristotle, became the subject of intense study and public interest. Their research showed that there were geographic differences in humpback whale songs and that we could tell apart populations just by using those songs, which change throughout their lives. So the whales were controlling their singing and subject to cultural influences. The Paynes had found dialects in whale song. Would we find the same for canids?

Despite their cultural popularity, wolf howls haven’t been the subject of focussed research until recently. Now, following the lead of marine biologists and ornithologists, and with improved sound recording equipment and analysis programs, researchers can study them in depth. The first step in understanding what animals are saying to one another is to figure out what aspects of the voice are functional and what parts are formed by the structure of the throat and mouth, or what is the piano and what is the tune. Studies since the 1960s have shown that the howls that have haunted our dreams for centuries can tell us a lot about the particular wolf vocalising. Like humans, each wolf has its own voice. Each pack also shares howl similarities, making different families sound distinct from each other (wolves respond more favourably to familiar howls). This much we knew. What we didn’t know was whether the differences seen between packs were true of subspecies or of species, and if an Indian wolf howl would be distinct from a Canadian one.

More questions follow. If howls from different subspecies are different, do the howls convey the same message? Is there a shared culture of howl-meanings, where an aggressive howl from a European wolf means the same thing as an aggressive howl of a Himalayan? And can a coyote differentiate between a red wolf howling with aggressive intent and one advertising the desire to mate? Even without grammar or syntax, howls can convey intent, and if the shape of the howl changes enough while the intent remains constant, the foundations of distinctive culture can begin to appear. [Continue reading…]

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