If you have ever wanted to know what it’s like to live life as a dolphin, take a trip into the blue abyss through James Nestor’s Deep: Freediving, Renegade Science, and What the Ocean Tells Us About Ourselves.
The book is a first-hand introduction to freediving. The underwater diving technique, sans-SCUBA gear, was, until recently, remarkably widespread among fishing communities worldwide since time untold. Freediving is still used today by a handful of traditional fishing folk — and by some devoted researchers who want to come face-to-face with their cetacean subjects.
Nestor explains that humans share some of the physiological faculties that are used by modern marine mammals, but that few of us landlubbers have any idea what we’re capable of. He learns from the masters how to hold his breath, virtually to the point of blacking out, and explains in vivid detail the seemingly frightening techniques that he is taught.
Along the way, Nestor introduces us to a group of extreme athletes that compete to stay underwater for the longest and to dive to the deepest depths. These athletes certainly know what they’re capable of — but they often overestimate their abilities, in a mad rush for glory within their small community, with sometimes crippling or even deadly results.
To reach greater depths than can be reached with lungfuls of air alone, the book also describes humanity’s error-plagued history of building machines that help us plunge to seemingly fathomless depths. It explains the biology of much of what we have found once we got there.
Deep is a wonderful read that will entrance even the most knowledgable of ocean experts.
This new addition to the burgeoning bookshelf of global warming riffs provides a probing history of generations of climate inaction, both in the U.S. and internationally. Philosopher Dale Jamieson, currently a professor of environmental studies at New York University, offers this definitive account of failed climate negotiations as he meticulously explains the repercussions of ceaseless political dithering on greenhouse gas pollution.
What’s most extraordinary about this book is that it took Jamieson almost 25 years to write, beginning the manuscript he was 40 years old, and finally finished when he had nearly reached 60.
“I would like to say that it was a labor of love, but it was really an avocation that became an obsession,” Jamieson writes in the book’s preface. “When people asked me why my first attempts to write a book on this subject failed, I would say that it was impossible to write the book until I knew how the story ended.”
A major emphasis of the book is how America’s leaders, Democrats and Republicans alike, have so far prevented the U.N. Framework Convention on Climate Change from delivering any kind of international agreement that could actually make a difference for the world. And it was the ongoing failures of international climate talks that finally spurred him to finish his manuscript. “When Copenhagen went down the way it did, I knew that I had the story that I wanted to tell,” he told me.
The depth of knowledge of this climate-watching veteran shines through in the clarity of his oft-depressing, but always intriguing, assemblage of facts and illuminating observations.
This is not a book that dwells on the technicalities of the science of climate change. It focuses instead on ethics and politics. It’s not always an easy read. But, particularly for those who spend more time immersed in climate science than in the politics or philosophy of the warming crisis, it’s a read that’s well worth the time.
Some Australian kids don’t believe in the Easter Bunny.
The clutches of chocolate and colored eggs hidden in the yards and living rooms of environmentally-aware households Down Under are deposited, through orifice unknown, by the Easter Bilby.
Browse the easter sweets selection in just about any Australian store right now and you’ll find foil-wrapped chocolate icons of the adorable outback-dwelling marsupials.
Rabbits are ravenous, fast-breeding, and destructive pests in Australia, where they were introduced by hunters and graziers during the 19th Century. The bare rabbit-resembling bilby, on the other hand, is a native Australian species that’s vulnerable to extinction. Celebrating the Easter Bilby helps Australian kids learn about the ecological importance of native mammals — while avoiding the awkward passions for invasive counterparts that the Easter Bunny can imbue.
The beauty of the bilby lies in its relationship with Australia’s fragile, old, and nutrient-poor land. It digs through arid and semi-arid soils, bioturbing them, improving water drainage and reducing flooding and erosion. The digging helps spread seeds. It creates microhabitats for bugs and fungi. It turns over soils and helps with nutrient cycling.
The effect of native Australian diggers, such as bilbies, echidnas, and wombats, is “increased plant vigour and resilience, increased biodiversity and consequently improved ecosystem functioning,” scientists wrote in a Mammal Review paper published last year.
But Australian ecosystems have been ravaged during the past two centuries by introduced species, including rabbits, pigs, and camels, and by land clearing. The native diggers are hunted by introduced cats and foxes. Those pressures have helped push half of the nation’s digging mammals toward extinction, the researchers concluded following an exhaustive review of scientific literature. “[T]he loss of digging mammals has contributed to the deterioration of ecosystems,” they wrote.
Rabbits dig as well — but they apparently do not dig deep enough to produce the same benefits as bilbies. Previous research has shown that digging bilbies foster 80 percent more seedlings than do digging rabbits.
“When bilbies, bandicoots, and bettongs dig for food, their diggings are deep, roughly-conical pits which penetrate deep into the soil layers,” Murdoch University wildlife biologist Trish Fleming, one of the coauthors of the Mammal Review paper, told Wonk on the Wildlife.
“Rabbits dig shallower pits, which disturb a large area of the top soil layers. This would expose the soil to drying out, which means it’s less suitable for soil microorganisms or for new seeds.”
Then there’s the wee issue of rabbit plagues. Looking out across an affected Australian farm, the land can appear as if it is moving.
“Rabbits feed on soft shoots of plants, and then will dig up any vegetation within reach, including the roots and bark off trees. In plague numbers, they wipe out any living plant material. There are expanses of productive lands which have never recovered from plagues of rabbits,” Fleming said.
So go and get stuffed with caramel, Easter Rabbit. Aussies don’t need your type sniffing about in their gardens.
As scientists have started to figure out what a mycorrhizal fungus really is, they’ve discovered that it might be a really fun guy.
I mean, ahem. They’ve discovered that it might really be fungi.
Genetic sequencing is revealing surprising secrets of arbuscular mycorrhizae. The discoveries are casting doubt on notions of fungal individuality and offering new ways of boosting the amount of food that’s grown the world over.
Mycorrhizal fungi, aka myco, are soil dwellers that forage for water and nutrients, which they exchange for sugars produced by photsynthesizing plants. As I explained recently in Grist, they cool the globe and boost crop yields.
Research during the past decade suggests that what many of us would assume was a single myco fungus might actually be lots of mini fungi bits — genetically diverse nuclei that live and work together inside what we would logically perceive to be a fungus. There, the nuclei collaborate to create long mycelia and hyphae that stretch from root to root, delivering water and nutrients up to the plants, and passing carbon from the plants down into the soil.
This proposed blend of different nuclei is called the heterokaryosis hypothesis (a heterokaryon is a cell containing genetically diverse nuclei) — and it’s highly controversial. A recently flurry of papers has concluded that it is flat-out wrong, but those findings have been criticized by scientists who subscribe to the hypothesis.
If correct, the hypothesis could help scientists solve a couple of longtime fungal mysteries.
For one thing, it could help explain how and why mycelia from seemingly different fungi fuse together as they snake through the soil.
It could also explain how these types of fungi reproduce. Molecular evidence tells us that the fungi exchange genes, which suggests that they are mating. But scientists have never been able to figure out quite how they’re doing it. The heterokaryosis hypothesis suggests it’s the nuclei within each fungus that are breeding. It appears that they are migrating through fusions between the hollow mycelia.
“Why this heterokaryosis thing is so important,” said Ian Sanders, a professor of evolutionary biology at the University of Lausanne, “is because — I believe — we can use these genetic differences among the nuclei to create fungi that make plants grow better.”
Sanders has been involved with research in Colombia, where fungi have been developed that boosted cassava yields by one fifth while requiring less fertilizer. The research program is being expanded to Africa, where cassava, a root vegetable similar to a potato, is a dietary staple.
The breakthroughs relied on breeding techniques that took advantage of fungal heterokaryosis. More such breakthroughs would mean bigger yields of crops, more food, and less world hunger.
(Speaking of food, it’s worth noting that the heterokaryosis theory has nothing to do with mushrooms. There are two main types of mycorrhizae. Endomycorrhizae, which are the subject of this article, are arbuscular. They pierce the roots of plants with tiny vesicles and arbuscules, which are microscopic organs that helped both kingdoms of life adapt to life on land some 460 million years ago. It is the other type of mycorrhizae, ectomycorrhizae, the less common and less ancient union that engulfs roots without penetrating them, that produces mushrooms.)
Endomycorrhizae fungi infuse the roots of nine out of ten crop varieties, yet we know precious little about them. That’s largely because of complications inherent in trying to study an organism that’s intricately woven into the body of another; the result of nearly a half billion years of interdependent evolution.
The heterokaryosis hypothesis has its detractors. They point to research, such as this paper published this month in PLOS Genetics, in which nuclei sampled from a single fungus were nearly genetically identical. Supporters of the hypothesis point to findings from other research where vast genetic diversity appears to have been discovered. Sample sizes in some of the experiments have been very low, and just a few strains have been analyzed, making all of the results highly contentious.
One believer in the hypothesis is Toby Kiers, a mycological researcher at Vrije Universiteit Amsterdam. “It’s a neat concept, because even within an individual you’ve got individuals,” she said.
[Kiers] has secured funding to watch mycelia squeeze through tiny mazes, peering at them through microscopes as they trade nutrients with plants for sugars under different conditions. The goal, she says, is to “study their decision-making skills.”
Kiers’s research will combine cutting-edge microscopy and mycology with old-fashioned breeding techniques in a bid to select the most useful fungal strains. “They’re quite easy to select on,” she said, “because there’s so much genetic variability — even within a single hyphae, within a single spore.”
Animals can evolve to survive global warming by changing their behavior and by changing their bodies. Butterflies are particularly sensitive to climate change, and changes in their behavior have been well documented — most notably in their migration patterns and ranges. North American Butterfly Association president Jeffrey Glassberg recently told the Maryland Independent that climate change is affecting Rhopalocera on a vast scale. “There’s a whole suite of butterflies whose ranges are retreating,” he said. (Such changes are the subject of Flight Behavior, a novel by Barbara Kingsolver dealing with climate change.)
And now comes the first evidence that butterfly larvae are changing the internal workings of their bodies to help them cope with warming temperatures.
University of North Carolina scientists studied the optimal feeding temperatures of Colias spp. caterpillars from California’s Sacramento Valley and Colorado’s Montrose Valley. The frequency of very hot days and nights at both sample sites have increased since the 1970s, when a similar study with the same caterpillar populations was conducted. Caterpillars feed best within specific temperature ranges, and the researchers discovered that the caterpillars have evolved to feed at higher temperatures. The results of the study were published in the journal Functional Ecology:
This study is among the ﬁrst to show population changes in physiological performance in response to recent climate change, although previous theoretical work has predicted such changes. While previous work has highlighted adaptation to seasonal timing, speciﬁcally photoperiodic cues, our work suggests that rapid adaptation to changing thermal regimes may also be an essential mechanism.
I asked lead researcher Jessica Higgins whether she thinks that butterflies are among the first organisms to adapt their physiologies to warming conditions — or whether she thinks this was just the first time that such changes have been detected by scientists.
“I do think that other organisms may be adapting, but we can’t detect it because of the lack of good historical data,” Higgins said. “What made my experiment so unique was that I had this snapshot of caterpillar physiology back in the 1970s. I was able to compare my results with what they previously found and then correlate it with temperature. I think my study highlights that there can be adaption to physiological traits — not just changes in seasonality, which has been the main focus of previous adaptation-to-climate studies. “
Great white sharks are among Earth’s most formidable predators. They are apex predators. They prey on fish, mammals and birds — but nothing preys on them.
And in Western Australia, the state government, tired of losing surfers and other beach-goers to the toothy jaws of these ferocious elasmobranchs, has become a predator.
“The preservation of human life is our number one priority,” said Troy Buswell, the state’s fisheries minister, in announcing new policies that will see white sharks killed if they venture within a kilometer of popular beaches. The state’s decision to cull sharks has sparked a global controversy, and polling suggests that even West Australians are overwhelmingly opposed.
“The decision by Western Australia officials to cull sharks off the coast is alarming,” said Ashley Blacow, a policy and communications official with nonprofit Oceana. “Sharks play a critical role in keeping ocean ecosystems healthy. The presence of sharks ultimately increases species stability and diversity of the overall ecosystem. White sharks in particular are a vulnerable species and they should be protected, not killed.”
One of Western Australia’s most controversial approaches to culling sharks will see floating drums placed around beaches, attached to baited hooks. The trapping equipment are known as “drum lines” — and conservationists regard them as appallingly cruel. Drum lines are illegal in many parts of the world, including in the U.S. One shark expert described the killing method as “archaic” in an interview with Nature.
“Drum lines are 55-gallon steel drums with heavy tackle-like chains or large lines connected to bait,” David McGuire, director of Shark Stewards, told us. “They’re usually anchored to the bottom or they can be linked in chains. I’ve seen them used illegally in Mexico to catch sharks. Essentially, the shark bites the bait, is hooked, and drowns.”
Perhaps most troublingly, there is a lack of scientific evidence that such culling actually protects humans from shark attacks. It might feel satisfying to kill a member of a species that has been killing humans, but that sense of satisfaction might be more of the revenge variety than anything else. Hawaii culled nearly 5,000 sharks between 1959 to 1976, yet there was no change in the rate at which sharks attacked humans in those same waters.
Unfortunately, it may take years of shark culling and shark attacks before the West Australian government can determine whether its new policies are having the effect that it desires.
“True effectiveness cannot be assessed by simply counting the number of sharks captured and killed,” writes University of Hawaii researcher Carl Mayer in an article published by The Conversation. “Demonstrable effectiveness means a measurable decrease in shark bite incidents in response to culling activities.”
Is it better to kill an orphaned fawn, or is it better to leave it alive, left to try to survive alone in a menacing world?
That unpalatable question is not a hypothetical one in Scotland, where some 60,000 red deer are culled every year — part of an effort to keep populations down to protect crops and woodlands from the hungry grazers.
“Shoot both female and juvenile where-ever possible,” the guidelines state. “Where possible target calves first and maintain vigilance for orphaned calves. ”
Josephine Pemberton, a professor at the Institute of Evolutionary Biology, University of Edinburgh, wanted to know whether that policy was scientifically wise. Using funding from the U.K. National Environmental Research Council, Pemberton and five other scientists analyzed data from censuses of a red deer population on Scotland’s Isle of Rum dating back to the 1970s.
What they found was that depriving a deer of its mother’s care and protection before its second birthday triggered resounding impacts. Orphaned males and females were more likely to grow haggard and die young. Males were hit particularly hard — and male orphans had trouble growing antlers as they matured, reducing their chances of winning mates and reproducing. As for female fecundity? “Although we failed to find evidence that female orphans paid a reproductive cost,” the scientists wrote in their paper, which was published in August in the journal Behavioral Ecology and Sociobiology, “we cannot discount an effect on female physical condition.”
Pemberton said the results show that young deer should be killed if they are orphaned by a hunter — even if they are old enough to not seem helpless.
“If anything, our results suggest that if a young animal is still going around with its mother in its second year — and they often do — you should try and shoot it then, too,” Pemberton said.
But that’s easier said than done. And not just because shooting a fawn must surely be a heartrending task for even a hardened stalker.
“Although culling calves with their mothers is in the best practice guidance, stalking is a tough job done largely alone,” Pemberton said. “Stalkers are often under pressure to shoot a lot of hinds. Shooting the pair takes time and effort and we know they don’t always manage to do it.”
Vast resources are plowed into measuring the metrics associated with global warming. Calculations reveal that American and European greenhouse gas emissions are falling while China’s are rising, and that more carbon dioxide is being pumped out worldwide every year than had been the case the year before. We know that carbon dioxide levels passed a record-breaking 400 parts-per-million point in May, well above the preindustrial level of 280 ppm, before dipping in line with normal seasonal fluctuations — that knowledge is courtesy of air monitoring in Hawaii and the findings of ice-core studies. And gravity-measuring satellites are used to estimate the rate at which glaciers are melting — revealing that despite harboring just 1 percent of the world’s land ice, these thawing rivers of ice are responsible for 29 percent of the rise of sea levels.
The results of these measurements don’t just keep us awake at night. They help policy-makers target efforts to reduce emissions and to prepare communities for changes in the climate.
But what about biodiversity?
Although the world is rallying around efforts to come to terms with its climate problem (even if not enough is being done to actually solve that problem), it is failing to measure the alarming decline of biodiversity, which by one recent estimate has fallen 30 percent in 40 years. It is not investing the resources needed to track the genetic stockpile contained in the cells of plants, animals, mushrooms and other forms of life as forests are bulldozed, rivers are diverted and acidifying oceans are overfished.
Every time a species or a jungle is lost, and every time environmental tumult helps generalists (such as ring-billed gulls) outcompete specialists (such as piping plovers), the world loses some of its genetic code. That code is critically important. It can help an ecosystem weather changes in the, well, in the weather, which is happening now more than ever in human history. It can help sustain a myriad of complex food chains that underpin the very functioning of the natural world. And it can present humans with chemical compounds that prove useful as new drugs or foods.
If we are to get a handle on the specifics of the biodiversity crisis, which we must do if we are to effectively manage the problem, then more scientists need to be trained and employed and provided with the resources needed to advance their fields.
The group held meetings in Malaysia this week to discuss two main topics: the measurement and assessment of genetic and biological resources; and the calculation of the value of key ecosystem services.
The conclusion: The world just isn’t doing enough to measure biodiversity.
“Of the estimated 10.8 million species on land and in the oceans, less than 2 million have been scientifically described,” IPBES chairman Zakri Abdul Hamid, science advisor to Malaysia’s prime minister, said in a statement published Wednesday at the end of the three days of talks. “If we don’t know what species there are out there, we don’t know what niche they fill in a healthy ecosystem or perhaps in remedying some human condition.” More from the statement:
Most world nations – unanimously committed to protecting biodiversity – nevertheless cannot measure and assess their genetic and biological resources, nor the value of key ecosystem services nature provides to them, international experts from 72 countries warned today.
In addition to taxonomists, nations lack economists able to put a value on the water purification, storm protection and other services of nature, which would inform trade-off choices in development planning. And fewer still deploy social scientists to estimate nature’s non-economic (e.g. cultural) values, or to find ways to effect needed changes in human attitudes and behaviour.
“There’s an old saying: We measure what we treasure. Unfortunately, though we profess to treasure biodiversity, most nations have yet to devote adequate resources to properly measure and assess it along with the value of ecosystem services,” Zakri said. “Correcting that is a priority assignment from the world community to IPBES.”
People infected with two closely-related species of fungi are dying in growing numbers in the American southwest. The Coccidioides spores are blown with dust into lungs, where they can trigger a painful and sometimes-deadly condition known as valley fever.
But any cocci that ends up in a human has hit a dead end. It will not reproduce to spawn a new generation.
That’s because of the lifecycle adopted by these varieties of cocci after evolving with the rodents that share their desert home. The coccis’ ancient ancestors lived and dined on plants. Then they evolved to feast instead on the rotting flesh of dead animals. Now they have evolved to live inside a living mammal, sometimes waiting for years for the host to die so they can pounce and quickly consume the fresh kill.
Mammals whose immune systems can’t control the fungus may die quickly. But as I explain in Vice’sMotherboard blog, most animals that are infected with cocci develop few symptoms — and those symptoms are normally short-lived:
Normally, [the Cocci] eek out lives as filaments called hyphae. The hyphae live in the soil and produce spores, a lucky few of which get sniffed into the lungs of desert rodents. The spores balloon in size inside the host, forming spherules. The mammal immune system kicks quickly into gear at this point, building walls around the spherules, containing them and developing immunity against further attacks.
It’s when the immune system fails to contain these spherules that the fungus can propagate throughout its victim, sometimes with deadly consequences. As an infected rodent dies, collapsing into the desert, the cocci burst out of suspended animation and unleash streamers of hyphae that eat the rotting meat. As the fungus feasts, hyphae and spores slip back into the soil, ready to start the cycle all over again.
Humans don’t slip into the desert sands when we die. We are embalmed or cremated, making any infection a waste of time for the fungus and, in some cases, a waste of life for humanity. “If a cocci spore gets into a human, it has made a big mistake,” John Taylor, a University of California at Berkeley mycologist, told me. “It’s unlikely to ever become adapted to living in humans.”
This summer has been a tinder-dry scorcher in the American West, where climate change is being blamed for a horror fire season. Mountain snow is melting earlier nowadays and summers are getting hotter — and that perilous partnership is fueling a steady surge in the frequency and size of the region’s wildfires.
The infernos kill firefighters, destroy homes and damage public infrastructure.
But it’s worth remembering that fires are healthy and regenerative phenomena in many ecosystems — including those in the West.
Blazes clear out water-hogging undergrowth and provide blank slates upon which timberlands can grow anew, boosting forest biodiversity. Rugged pods that encase the seeds of some specialized plants open after fire, sowing the genesis of the next generation in fertile fields wiped clean of competitors.
It’s not just plants that have evolved to rely on fire. Woodpeckers, for example, can flourish in its wake. The black-backed woodpecker has a particularly specialized diet that leaves it dependent upon the charred aftermath of wildfires. The species feasts on the wood-boring beetles that proliferate in burned trees following blazes in Western American mountain-ranges.
But us humans are not as fond of fire as are the beetles or the woodpeckers that hunt them. Public policy dictates that fires should be avoided and, if that fails, confronted without compromise. The practice of preemptively thinning out forests to reduce fire impacts, and the logging of forests after they burn, have both taken heavy tolls on the black-backed woodpeckers.
Populations of these birds have been harmed so severely by public policies of wildfire suppression that the federal government is reviewing whether genetically distinct populations in two regions should be added to its list of endangered species.
“This is the first time in the history of the Endangered Species Act that the government has initiated steps to protect a wildlife species that depends upon stands of fire-killed trees,” Chad Hanson, an ecologist with Earth Island Institute, said when the U.S. Fish & Wildlife Service announced the review in June.
Hanson coauthored research published in May in The Open Forest Science Journal that showed just how severely one of those two populations of woodpeckers, which lives in the Sierra Nevada and southern Cascade ranges of California and Oregon, has been affected by humanity’s wont to battle fire. Hanson and his colleague, Dennis Odion, obtained data from the government and from their own observations which they used to model the effects of typical wildfire suppression policies in the Sierra on the species’ habitat.
“A scenario based on thinning 20 percent of mature forests over a 20-year period, and post-fire logging in 33 percent of potential habitat created by fire, reduced the amount of primary habitat after 27 years to 30 percent of the amount that would occur without these treatments,” the scientists wrote in the paper.
“Our results indicate that conserving the distinct population of black-backed woodpeckers in the southern Cascades and Sierra Nevada and the biodiversity for which they are an indicator will require that more unthinned area be burned by wildfires and protected after fire as critical habitat.”
The following table was lifted from the paper. It compares the amount of black-backed woodpecker habitat available within a study area following 27 years of simulated fire suppression policies:
And this photograph of an acorn placed in the trunk of a Rim Fire-charred pine is an endearing reminder that wildlife perseveres following fire. Wild Equity Institute founder Brent Plater tells me it might have been put there by a squirrel or a scrub jay — but that it was most likely the handiwork of an acorn woodpecker. “Caching acorns in tree cavities is what they do for a living,” he said.