How bacteria help regulate blood pressure

Veronique Greenwood writes: Some years ago, when Jennifer Pluznick was nearing the end of her training in physiology and sensory systems, she was startled to discover something in the kidneys that seemed weirdly out of place. It was a smell receptor, a protein that would have looked more at home in the nose. Given that the kidneys filter waste into urine and maintain the right salt content in the blood, it was hard to see how a smell receptor could be useful there. Yet as she delved deeper into what the smell receptor was doing, Pluznick came to a surprising conclusion: The kidney receives messages from the gut microbiome, the symbiotic bacteria that live in the intestines.

In the past few years, Pluznick, who is now an associate professor of physiology at Johns Hopkins University, and a small band of like-minded researchers have put together a picture of what the denizens of the gut are telling the kidney. They have found that these communiqués affect blood pressure, such that if the microbes are destroyed, the host suffers. The researchers have uncovered a direct, molecular-level explanation of how the microbiome conspires with the kidneys and the blood vessels to manipulate the flow of blood.

The smell receptor, called Olfr78, was an orphan at first: It had previously been noticed in the sensory tissues of the nose, but no one knew what specific scent or chemical messenger it responded to. Pluznick began by testing various chemical possibilities and eventually narrowed down the candidates to acetate and propionate. These short-chain fatty acid molecules come from the fermentation breakdown of long chains of carbohydrates — what nutritionists call dietary fiber. Humans, mice, rats and other animals cannot digest fiber, but the bacteria that live in their guts can.

As a result, more than 99 percent of the acetate and propionate that floats through the bloodstream is released by bacteria as they feed. “Any host contribution is really minimal,” Pluznick said. Bacteria are therefore the only meaningful source of what activates Olfr78 — which, further experiments showed, is involved in the regulation of blood pressure. [Continue reading…]

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The scallop sees its world with hundreds of space-age eyes

Carl Zimmer writes: It’s hard to see what’s so special about a scallop. It looks a lot like a clam, mussel or any other bivalve. Inside its hinged shell lurks a musclebound creature that’s best enjoyed seared in butter.

But there’s something more to this ubiquitous entree: the scallop sees its world with hundreds of eyes. Arrayed across the opening of its shell, the eyes glitter like an underwater necklace. Each sits at the tip of its own tentacle and can be extended beyond the rim of the shell.

While some invertebrate eyes can sense only light and dark, scientists have long suspected that scallops can make out images, perhaps even recognizing predators quickly enough to jet away to safety. But scallop eyes — each about the size of a poppy seed — are so tiny and delicate that scientists have struggled to understand how they work.

Now, a team of Israeli researchers has gotten a look at the hidden sophistication of the scallop eye, thanks to powerful new microscopes. On Thursday, they reported in the journal Science that each eye contains a miniature mirror made up of millions of square tiles. The mirror reflects incoming light onto two retinas, each of which can detect different parts of the scallop’s surroundings.

Our own eye has been likened to a camera: it uses a lens to focus light on the retina. The new research suggests that scallop eyes are more akin to another kind of technology: a reflector telescope of the sort first invented by Newton. Today, astronomers build gigantic reflector telescopes to look in deep space, and they also build their mirrors out of tiles.

“For me, Newton and Darwin come together in these eyes,” said Gáspár Jékely, a neuroscientist at the University of Exeter who was not involved in the new study. [Continue reading…]

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Bacteria from outer space rendezvous with Russians at International Space Station?

National Geographic reports: Living bacteria have been found on the outside of the International Space Station, a Russian cosmonaut told the state news agency TASS this week.

Anton Shkaplerov, who will lead Russia’s ISS crew in December, said that previous cosmonauts swabbed the station’s Russian segment during spacewalks and sent the samples back to Earth. The samples came from places on the station that had accumulated fuel waste, as well as other obscure nooks and crannies. Their tests showed that the swabs held types of bacteria that were not on the module when it originally launched into orbit, Shkaplerov says.

In his interview with TASS, Shkaplerov says the bacteria “have come from outer space and settled along the external surface”—a claim that sparked some media outlets to issue frenzied reports about aliens colonizing the space station.

For now, though, details about the swabbing experiment are thin on the ground. Shkaplerov did not note whether the study has been vetted by a peer-reviewed journal, which means it’s unclear exactly when and how the full experiment was conducted, or how the team avoided any contamination from much more mundane bacteria on the cosmonauts or in the Earth-bound lab. Interview requests with the Russian space agency were unanswered when this article went to press.

Rather than microbes raining down from outer space, it’s much more plausible that the outside of the space station became contaminated by earthly organisms, many of which can survive in the harsh environment in orbit. [Continue reading…]

Indeed, the journey along Occam’s Razor is much shorter and vastly easier than any voyage from distant worlds.

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Cockatoos match shapes better than primates

James Gorman writes: Cockatoos are smart birds, and the Goffin’s cockatoos in a Vienna lab are among the smartest. In an experiment reported about a year ago, they turned out to be real stars at making tools from a variety of materials in order to get a treat.

In a new study, researchers tested the birds’ ability to match shapes using an apparatus reminiscent of a child’s toy. The birds had to put a square tile into a square hole and more complicated, asymmetrical shapes into matching holes. If they were successful, they got a treat.

Cornelia Habl, a master’s student at the University of Vienna, and Alice M. I. Auersperg, a researcher at the University of Veterinary Medicine in Vienna, ran several experiments. They reported in the journal PLOS One that the cockatoos were not only able to match the shapes to the holes, but did much better than monkeys or chimpanzees.

“It was thought to be an exclusively human ability for a long time,” Ms. Habl said. Tests of matching shapes are used to mark milestones in child development.

Babies can put a sphere into the right hole at age 1, but they can’t place a cube until age 2. From there, they continue to improve.

Some primates can do similar tasks, although they need a lot of basic training to get up to speed before they can use the experimental apparatus, called a key box.

The birds jumped right in without any training and excelled. “Compared to primates, the cockatoos performed very well,” Ms. Habl said.

Why are they so good? In the wild, they haven’t been observed using tools. But they are generalists, foragers who take whatever food they can find. [Continue reading…]

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Young again: How one cell turns back time

Carl Zimmer writes: None of us was made from scratch. Every human being develops from the fusion of two cells, an egg and a sperm, that are the descendants of other cells. The lineage of cells that joins one generation to the next — called the germline — is, in a sense, immortal.

Biologists have puzzled over the resilience of the germline for 130 years, but the phenomenon is still deeply mysterious.

Over time, a cell’s proteins become deformed and clump together. When cells divide, they pass that damage to their descendants. Over millions of years, the germline ought to become too devastated to produce healthy new life.

“You take humans — they age two, three or four decades, and then they have a baby that’s brand new,” said K. Adam Bohnert, a postdoctoral researcher at Calico Life Sciences in South San Francisco, Calif. “There’s some interesting biology there we just don’t understand.”

On Thursday in the journal Nature, Dr. Bohnert and Cynthia Kenyon, vice president for aging research at Calico, reported the discovery of one way in which the germline stays young.

Right before an egg is fertilized, it is swept clean of deformed proteins in a dramatic burst of housecleaning. [Continue reading…]

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Bacteria slow their DNA repair to a crawl in favor of proofreading RNA gene transcripts

Jordana Cepelewicz writes: Evolution is a game of trade-offs. Every trait an organism inherits may have benefits and drawbacks; what matters to natural selection is whether the trait is positive or negative on balance. But in a recent study, researchers described a balancing act that seems more counterintuitive than most: Bacterial cells prioritize transcription — the process of making RNA transcripts of genes as the first step in protein production — over repairing double-strand breaks in their DNA.

“We tend to think of DNA as the brains of the cell,” said Susan Rosenberg, a biologist at Baylor College of Medicine in Houston. “If we push that analogy and think about parts of the cell competing for resources the way the parts of the body do, the brain should be getting whatever it needs at the expense of everything else.”

So when her Baylor colleague Christophe Herman approached her with the hypothesis that transcription might be more important than DNA repair, Rosenberg was ready to bet the other way. “And I was sure I would win,” she said.

But she was proven wrong. Last month, she, Herman and their team published the results of their research in Nature: They found, using a series of experiments and intricate controls, that transcription can trump DNA repair in E. coli. [Continue reading…]

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Dogs attempt to communicate with us through facial expressions

Gemma Tarlach writes: Hey dog owners, you’re not imagining it: Researchers think your pooch may be trying to say something with a pout or pleading eyes.

Everyone who lives with dogs may be rolling their eyes right about now and saying “Of course Boopsie/Rex/Potato is smiling/frowning/expressing wide-eyed existential dread,” but heaps of anecdotal evidence don’t mean much in terms of scientific cred. A study out today, however, is a big step toward confirming that dogs use facial expressions in an attempt to communicate with humans.

Within our extended primate clan, particularly orangutans and gibbons, there is evidence that individuals modulate their facial expressions based on whether there’s an audience, which suggests they’re using the expressions as a form of communication. But there’s been no evidence that’s the case among non-primates — their facial expressions have generally been considered involuntary and reflexive displays of emotion.

Interested in testing that notion, reasearchers from the University of Portsmouth designed an experiment to determine whether the facial expressions of dogs change in the presence of a human audience. [Continue reading…]

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Sheep learned to recognize photos of Obama and other celebrities, neuroscientists say

Ben Guarino writes: Of the roughly 1.1 billion sheep on Earth, roughly 1.1 billion have no idea who Barack Obama is. But there are at least eight sheep who can recognize the former president by his face. After a few days of training at the University of Cambridge in England, the animals learned to select the former president’s portrait out of a collection of photos.

Recognizing Obama meant the sheep won a snack. The scientists, in turn, were rewarded with better ways to measure sheep brain function.

Sheep are about as capable of recognizing faces as monkeys or humans, University of Cambridge researchers report Tuesday in the journal Royal Society Open Science. The Cambridge flock, eight female Welsh Mountain sheep, successfully learned the faces of four celebrities in a recent experiment: Obama, British newscaster Fiona Bruce and actors Emma Watson and Jake Gyllenhaal.

“Sheep are capable of sophisticated decision making,” said study author Jenny Morton, a neurobiologist at the University of Cambridge. Seven years ago, she said, she bought these sheep out of the back of a truck on its way to a slaughterhouse. Morton, who studies Huntington’s disease, uses them as a stand-in for humans, in part because “sheep have large brains with humanlike anatomy.” [Continue reading…]

Like many other research findings, this will garner the response than animals turn out not to be as stupid as humans are inclined to believe.

This experiment, however, invites a rather obvious follow-up: a test to measure the human capacity to recognize sheep’s faces.

I predict that on this score, the human capacity is probably inferior to that of the sheep, which is to say that our anthropocentric habits have rendered us as among the least perceptive of creatures.

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The physics of life

Jeremy England writes: Living things are so impressive that they’ve earned their own branch of the natural sciences, called biology. From the perspective of a physicist, though, life isn’t different from non-life in any fundamental sense. Rocks and trees, cities and jungles, are all just collections of matter that move and change shape over time while exchanging energy with their surroundings. Does that mean physics has nothing to tell us about what life is and when it will appear? Or should we look forward to the day that an equation will finally leap off the page like a mathematical Frankenstein’s monster, and say, once and for all, that this is what it takes to make something live and breathe?

As a physicist, I prefer to chart a course between reductionism and defeat by thinking about the probability of matter becoming more life-like. The starting point is to see that there are many separate behaviours that seem to distinguish living things. They harvest energy from their surroundings and use it as fuel to make copies of themselves, for example. They also sense, and even predict things about the world they live in. Each of these behaviours is distinctive, yes, but also limited enough to be able to conceive of a non-living thing that accomplishes the same task. Although fire is not alive, it might be called a primitive self-replicator that ‘copies’ itself by spreading. Now the question becomes: can physics improve our understanding of these life-like behaviours? And, more intriguingly, can it tell us when and under what conditions we should expect them to emerge?

Increasingly, there’s reason to hope the answer might be yes. The theoretical research I do with my colleagues tries to comprehend a new aspect of life’s evolution by thinking of it in thermodynamic terms. When we conceive of an organism as just a bunch of molecules, which energy flows into, through and out of, we can use this information to build a probabilistic model of its behaviour. From this perspective, the extraordinary abilities of living things might turn out to be extreme outcomes of a much more widespread process going on all over the place, from turbulent fluids to vibrating crystals – a process by which dynamic, energy-consuming structures become fine-tuned or adapted to their environments. Far from being a freak event, finding something akin to evolving lifeforms might be quite likely in the kind of universe we inhabit – especially if we know how to look for it. [Continue reading…]

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What is an individual in nature?

Derek J Skillings writes: When she was two years old, I took my daughter to the American Museum of Natural History for the first time. As we strolled through the displays of taxidermy animals, she would waddle towards each one, and point and ask what we were looking at. When we entered the Hall of African Mammals, she was so overwhelmed by the presence of her storybook companions that she could only manage to jump up and down on the spot while shouting a mishmash of half-formed names. Leophant! Zeepotamus! Seeing her favourite animals was the highlight of her day, but mine was reliving the excitement of discovering strange new beings, as my daughter asked, wide-eyed, over and over again: what’s that?

Most of the time the living world appears to us as manageable chunks. Even a toddler can see that. We know if we have one dog or two; at a pinch, we can probably count how many trees are growing in our backyard. Natural history museums started, in part, as embodiments of early scientific approaches to ordering and cataloguing the diversity of life. This is possible only because humans can usually intuitively pick out one organism from the next – that is, because most of the creatures we come across have pretty clear boundaries in space and time. When my daughter and I stood back and considered a herd of frozen elephants walking in a line at the museum, it was clear – even for a baby with its trunk wrapped tenderly around its mother’s – where one elephant ended and another began.

How come, then, the meaning of individuality is one of the oldest and most vexing problems in biology? For millennia, naturalists and philosophers have struggled to define the most fundamental units of living systems and to delimit the precise boundaries of the organisms that inhabit our planet. This difficulty is partly a product of the search for a singular theory that can be used to carve up all of the living world at its joints. But my view is that no such unified theory exists; there’s no single answer to the question: ‘What parts of the world are a part of you as a biological individual, and what parts are not?’ Different accounts of individuality pick out different boundaries, like an overlapping Venn diagram drawn on top of a network of biotic interactions. This isn’t because of uncertainty or a lack of information; rather, the living world just exists in such a way that we need more than one account of individuality to understand it.

When you stop to think about it, the problem of individuality is (ironically enough) actually composed of two problems: identity and individuation. The problem of identity asks: ‘What does it mean for a thing to remain the same thing if it changes over time?’ or ‘What makes two entities the same kind of thing?’ The problem of individuation asks: ‘How do we tell things apart?’ or ‘What are the boundaries of an object?’ Identity is fundamentally about the nature of sameness and continuity; individuation is about differences and breaks. [Continue reading…]

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A giant insect ecosystem is collapsing due to humans. It’s a catastrophe

Michael McCarthy writes: Thirty-five years ago an American biologist Terry Erwin conducted an experiment to count insect species. Using an insecticide “fog”, he managed to extract all the small living things in the canopies of 19 individuals of one species of tropical tree, Luehea seemannii, in the rainforest of Panama. He recorded about 1,200 separate species, nearly all of them coleoptera (beetles) and many new to science; and he estimated that 163 of these would be found on Luehea seemannii only.

He calculated that as there are about 50,000 species of tropical tree, if that figure of 163 was typical for all the other trees, there would be more than eight million species, just of beetles, in the tropical rainforest canopy; and as beetles make up about 40% of all the arthropods, the grouping that contains the insects and the other creepy-crawlies from spiders to millipedes, the total number of such species in the canopy might be 20 million; and as he estimated the canopy fauna to be separate from, and twice as rich as, the forest floor, for the tropical forest as a whole the number of species might be 30 million.

Yes, 30 million. It was one of those extraordinary calculations, like Edwin Hubble’s of the true size of the universe, which sometimes stop us in our tracks.

Erwin reported that he was shocked by his conclusions and entomologists have argued over them ever since. But about insects, his findings make two things indisputably clear. One is that there are many, many more types than the million or so hitherto described by science, and probably many more than the 10m species sometimes postulated as an uppermost figure; and the second is that this is far and away the most successful group of creatures the Earth has ever seen.

They are multitudinous almost beyond our imagining. They thrive in soil, water, and air; they have triumphed for hundreds of millions of years in every continent bar Antarctica, in every habitat but the ocean. And it is their success – staggering, unparalleled and seemingly endless – which makes all the more alarming the great truth now dawning upon us: insects as a group are in terrible trouble and the remorselessly expanding human enterprise has become too much, even for them.

Does it matter? Oh yes. Most of our fruit crops are insect-pollinated, as are the vast majority of our wild plants
The astonishing report highlighted in the Guardian, that the biomass of flying insects in Germany has dropped by three quarters since 1989, threatening an “ecological Armageddon”, is the starkest warning yet; but it is only the latest in a series of studies which in the last five years have finally brought to public attention the real scale of the problem. [Continue reading…]

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Insectageddon: Farming is more catastrophic than climate breakdown

George Monbiot writes: Which of these would you name as the world’s most pressing environmental issue? Climate breakdown, air pollution, water loss, plastic waste or urban expansion? My answer is none of the above. Almost incredibly, I believe that climate breakdown takes third place, behind two issues that receive only a fraction of the attention.

This is not to downgrade the danger presented by global heating – on the contrary, it presents an existential threat. It is simply that I have come to realise that two other issues have such huge and immediate impacts that they push even this great predicament into third place.

One is industrial fishing, which, all over the blue planet, is now causing systemic ecological collapse. The other is the erasure of non-human life from the land by farming.

And perhaps not only non-human life. According to the UN Food and Agriculture Organisation, at current rates of soil loss, driven largely by poor farming practice, we have just 60 years of harvests left. And this is before the Global Land Outlook report, published in September, found that productivity is already declining on 20% of the world’s cropland.

The impact on wildlife of changes in farming practice (and the expansion of the farmed area) is so rapid and severe that it is hard to get your head round the scale of what is happening. A study published this week in the journal Plos One reveals that flying insects surveyed on nature reserves in Germany have declined by 76% in 27 years. The most likely cause of this Insectageddon is that the land surrounding those reserves has become hostile to them: the volume of pesticides and the destruction of habitat have turned farmland into a wildlife desert.

It is remarkable that we need to rely on a study in Germany to see what is likely to have been happening worldwide: long-term surveys of this kind simply do not exist elsewhere. This failure reflects distorted priorities in the funding of science. There is no end of grants for research on how to kill insects, but hardly any money for discovering what the impacts of this killing might be. Instead, the work has been left – as in the German case – to recordings by amateur naturalists.

But anyone of my generation (ie in the second bloom of youth) can see and feel the change. We remember the “moth snowstorm” that filled the headlight beams of our parents’ cars on summer nights (memorialised in Michael McCarthy’s lovely book of that name). Every year I collected dozens of species of caterpillars and watched them grow and pupate and hatch. This year I tried to find some caterpillars for my children to raise. I spent the whole summer looking and, aside from the cabbage whites on our broccoli plants, found nothing in the wild but one garden tiger larva. Yes, one caterpillar in one year. I could scarcely believe what I was seeing – or rather, not seeing.

Insects, of course, are critical to the survival of the rest of the living world. Knowing what we now know, there is nothing surprising about the calamitous decline of insect-eating birds. Those flying insects – not just bees and hoverflies but species of many different families – are the pollinators without which a vast tract of the plant kingdom, both wild and cultivated, cannot survive. The wonders of the living planet are vanishing before our eyes. [Continue reading…]

Out of sight, out of mind — the issue here is not just generational in the sense experienced by those of us old enough to remember insects, birds, and other creatures in greater numbers. The issue is above all one that springs from the physical separation between humans and nature in a world where humans experience life predominantly inside cities and predominantly as the seemingly most commonplace species.

I happen to live in a town where squirrels undoubtedly outnumber humans and where bears can show up in the most unexpected places and yet even here, for most people most of the time, nature remains in the background of human affairs.

While the rapid demise of flying insects should provoke alarm in anyone with even just a rudimentary understanding of the interdependence of species, a more commonplace response is likely to be that this loss signifies a welcome reduction in unwanted pests — fewer mosquitoes, fewer flies, and less irritants to complain about.

When it comes to human appreciation for non-human forms of life, insects get short shrift.

Butterflies are admired and yet most people would be hard pressed to name a single species, let alone recognize and appreciate any species in its larval form.

Bees are appreciated as productive, yet potentially dangerous and to most people indistinguishable from wasps.

Ants are lauded in the abstract as exemplars of industry and complex social organization and yet bound to suffer swift extermination when they turn up where they’re unwelcome.

Even so, the objective truth that insects would grasp if they had the cognitive capacities to do so is that the most prolific forms of life that have lived sustainably on this planet for hundreds of millions of years are now at risk from the life-threatening effects of human infestation.

No, this isn’t an argument for the elimination of humans, but as the late-comers on the stage of life, we have to do a hell of a lot better learning how to harmoniously co-exist with the creatures around us. Not only do their lives depend on this, but so do ours.

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Warning of ‘ecological Armageddon’ after dramatic plunge in insect numbers

The Guardian reports: The abundance of flying insects has plunged by three-quarters over the past 25 years, according to a new study that has shocked scientists.

Insects are an integral part of life on Earth as both pollinators and prey for other wildlife and it was known that some species such as butterflies were declining. But the newly revealed scale of the losses to all insects has prompted warnings that the world is “on course for ecological Armageddon”, with profound impacts on human society.

The new data was gathered in nature reserves across Germany but has implications for all landscapes dominated by agriculture, the researchers said.

The cause of the huge decline is as yet unclear, although the destruction of wild areas and widespread use of pesticides are the most likely factors and climate change may play a role. The scientists were able to rule out weather and changes to landscape in the reserves as causes, but data on pesticide levels has not been collected.

“The fact that the number of flying insects is decreasing at such a high rate in such a large area is an alarming discovery,” said Hans de Kroon, at Radboud University in the Netherlands and who led the new research.

“Insects make up about two-thirds of all life on Earth [but] there has been some kind of horrific decline,” said Prof Dave Goulson of Sussex University, UK, and part of the team behind the new study. “We appear to be making vast tracts of land inhospitable to most forms of life, and are currently on course for ecological Armageddon. If we lose the insects then everything is going to collapse.” [Continue reading…]

I often get the impression that many of the people who dismiss dire warnings about environmental collapse and climate change have a fabulously inflated faith in the human capacity to solve problems through technical solutions, combined with an attitude that the natural world is in some fundamental sense superfluous to human needs. Seemingly, nature needs protecting mostly because it provides pleasant locations for vacations.

Nevertheless, experiments in the creation of closed ecological systems should have already shattered any illusions about the capacity for humanity to survive on an ecologically wrecked planet through artificial means.

But maybe the cavalier attitude that many decision-makers display in the exercise of their responsibility to protect the ecosystem on which all of life depends is ultimately a reflection of the cynicism and selfishness of individuals who simply don’t care much about the continuation of life after the end of their own.

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How toxic PCBs came to permeate life on Earth

Rebecca Altman writes: Deep in the Mariana Trench, at depths lower than the Rockies are high, rests a tin of reduced-sodium Spam.

NOAA scientists caught sight of it last year near the mouth of the Mariana’s Sirena Deep. It isn’t an isolated incursion, but it was nevertheless startling, the sight of those timeless golden letters bright against the deep ocean bottom.

Shortly after came news from another team of scientists who had found in the Mariana an innovation less familiar than shelf-stable meat, but far more significant. In the bodies of deep-dwelling creatures were found traces of industrial chemicals responsible for the rise of modern America—polychlorinated biphenyls.

PCBs had been detected in Hirondellea gigas, tiny shrimp-like amphipods scooped up by deepwater trawlers. Results from the expedition, led by Newcastle University’s hadal-zone expert Alan Jamieson, were preliminary released last year and then published in February.

PCBs have been found the world over—from the bed of the Hudson River to the fat of polar bears roaming the high Arctic—but never before in the creatures of the extreme deep, a bioregion about which science knows relatively little.

How PCBs reached the Mariana is still under investigation. Jamieson and colleagues speculated on multiple, regional sources. A nearby military base. The industrial corridors along the Asian coastline. And the Great Pacific Garbage Patch, where PCBs glom onto plastic particles caught in the current. Over time, the plastic degrades and descends into the depths, ferrying PCBs with them.

But the true origin of PCBs lies in another time and place, in Depression-era Alabama, and before that, 19th-century Germany at the pinnacle of German chemistry. [Continue reading…]

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The thermodynamic theory of ecology

Veronique Greenwood writes: Ecologists study the connections between species and their environment, traditionally through detailed observations of the natural world. They might penetrate far into a rainforest, learning the calls of birds one by one until they identify one they’ve never heard before. They might, as Harte does, monitor a single meadow for decades, becoming deeply versed in the details of each creature’s existence. Many are also interested in high-level, abstract questions, such as how birds first began to flock. But the field is rooted in a kind of natural history.

Macroecology deals with patterns that might be universal across ecosystems. When the field arose in the 1970s, ecologists tried to model the environment as a well-oiled machine that, given enough time, would settle into certain patterns. Yet when it became clear how much messier the real world is than those models, the field went quiet. “We were trying to answer bigger questions than our data could support,” said William Kunin, a professor of ecology at University of Leeds in the U.K. who watched the field evolve as an undergraduate in the 1970s.

In the late 1990s and early 2000s, macroecology rose again, driven by the need to understand the effects of mass deforestation, climate change and other large-scale changes in the environment. “We’re in a situation where there are big global-scale trends in species distributions, in climates, in fertilization of the planet. We’re doing big things to the world,” said Kunin, who now does macroecology work. “And policymakers want from us answers of what that will do to biodiversity.” Vanessa Weinberger, a doctoral student at the Pontifical Catholic University of Chile who has interned with [John] Harte [who has developed what he calls the maximum entropy (MaxEnt) theory of ecology], adds: “What these people started to do was to try to come up with laws of ecology.” [Continue reading…]

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Microbes that eat electricity

Emily Singer writes: [In 2015], biophysicist Moh El-Naggar and his graduate student Yamini Jangir plunged beneath South Dakota’s Black Hills into an old gold mine that is now more famous as a home to a dark matter detector. Unlike most scientists who make pilgrimages to the Black Hills these days, El-Naggar and Jangir weren’t there to hunt for subatomic particles. They came in search of life.

In the darkness found a mile underground, the pair traversed the mine’s network of passages in search of a rusty metal pipe. They siphoned some of the pipe’s ancient water, directed it into a vessel, and inserted a variety of electrodes. They hoped the current would lure their prey, a little-studied microbe that can live off pure electricity.

The electricity-eating microbes that the researchers were hunting for belong to a larger class of organisms that scientists are only beginning to understand. They inhabit largely uncharted worlds: the bubbling cauldrons of deep sea vents; mineral-rich veins deep beneath the planet’s surface; ocean sediments just a few inches below the deep seafloor. The microbes represent a segment of life that has been largely ignored, in part because their strange habitats make them incredibly difficult to grow in the lab.

Yet early surveys suggest a potential microbial bounty. A recent sampling of microbes collected from the seafloor near Catalina Island, off the coast of Southern California, uncovered a surprising variety of microbes that consume or shed electrons by eating or breathing minerals or metals. El-Naggar’s team is still analyzing their gold mine data, but he says that their initial results echo the Catalina findings. Thus far, whenever scientists search for these electron eaters in the right locations — places that have lots of minerals but not a lot of oxygen — they find them. [Continue reading…]

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Chimpanzees learn to use tools on their own, no teaching required

Leah Froats writes: As it turns out, chimpanzees don’t need to see in order to do, no matter what the old mantra might lead you to believe.

A common belief among researchers is that chimps need to watch other members of their communities use tools before they can pick the behavior up. In a study published in PeerJ in September, researchers from the University of Birmingham, and the University of Tübingen challenged this belief and checked to see if it would hold for a specific kind of tool use.

They attempted to recreate a behavior commonly found in the wild: the use of sticks to scoop algae from the water to eat. Would chimpanzees that were unfamiliar with this behavior be able to figure it out on their own? [Continue reading…]

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Tool-wielding macaques are wiping out shellfish populations

Nathaniel Scharping reports: The advent of tools was a big deal for humanity. It made it far easier to manipulate our environment and mold the planet to serve our own interests—from the folsom point to the iPhone X.

Some animals use tools too, like the macaques of Thailand, who have figured out that their favorite shellfish snacks are much easier to eat if they bash them open with rocks first. They’ve become proficient shellfish smashers, so much so that the macaques are actually threatening the existence of oysters and snails an a small island there. It’s a tale of technology gone wrong — only this time, humans aren’t the villains.

Researchers from Thailand, Europe and Australia looked at two groups of long-tailed macaques on separate islands off the Thai coast. The two locations, both alike in shellfish populations, differed only in the number of macaques there. Koram is host to around 80 primates, while NomSao has but nine. Both groups have figured out how to use rocks to break open shellfish armor, behavior that has been observed among other groups of macaques in Thailand.

On Koram, though, the abundance of tool-wielding macaques has led to a crisis of sorts. In a paper published last week in the journal eLife, the researchers estimate that a single individual on the island slurps down 47 shellfish a day, mostly oysters. For the mere 26 macaques that the researchers studied, that works out to 441,000 a year. Looking at periwinkles, a small sea snail, the researchers estimated that the monkeys could eat the entire island’s population in just a year. On NomSao, the much smaller group eats only about an eighth of the available periwinkle population. [Continue reading…]

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