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Environmental Change, Written in the DNA of Birds

Two studies of California bird populations show how shifting environments can rewrite animals’ genomes — for better or worse. The post Environmental Change, Written in the DNA of Birds appeared first on The Revelator.

As the environment shifts — due to climate change, habitat destruction, or other threats — we can often observe some of the ways that wildlife responds. Populations may decline. Individual animals may move. Some species may alter their behavior. But at the same time, scientists warn, wild plants or animals may experience harder-to-detect changes — for example, alterations to their genomes, the very DNA that defines them. It requires a sophisticated genetics laboratory to see these otherwise invisible changes at first, but they may have important implications for populations’ futures. How exactly can threats such as climate change and habitat loss have hidden effects on a species’ genetic code? Two studies on California birds, both published in the past year, illustrate the potential — both beneficial and problematic. A New Adaptation The endangered southwestern willow flycatcher (Empidonax traillii extimus), ranging from California east to New Mexico and Colorado, depends on rapidly disappearing riparian habitats. As those riverbanks dry up, scientists began to wonder how the birds have adapted. They found the answers by looking to the past. Photo: USFWS In summer 2023 a group of scientists published a study comparing the genomes of flycatcher specimens collected in the San Diego around the turn of the 20th century — taxidermied birds preserved in museums — with those of contemporary birds, using blood samples collected from individuals captured across willow flycatchers’ breeding range today. The study was only possible due to rapid advances in technology. “Until recently, it was very difficult to sequence historical specimens across their entire genome,” says Sheela Turbek, a postdoctoral fellow at Colorado State University who led the project. “DNA tends to degrade over time, and older specimens can have really low DNA concentrations.” The results surprised Turbek and her colleagues: San Diego flycatchers’ genetic diversity has increased over time. Most notably, this increased diversity included areas of the genome linked with climate adaptation. According to the study, it appears the San Diego birds have bred with flycatchers originally from populations in other areas of the West, which may have moved in response to local habitat losses. And as natural selection has acted on this increased diversity, the San Diego birds’ genomes have shifted away from those of neighboring populations, potentially making the local birds better suited for life in a wetter, more humid environment being shaped by climate change. It’s the first time, as far as Turbek knows, that genetic adaptation to climate change has been documented in a wild bird population. “These genetic changes are imperceptible to the human eye, and we don’t know exactly what [these genes] are controlling,” says Turbek, “but we were able to identify several genes that are likely involved in heat tolerance and the birds’ ability to effectively dissipate heat in humid environments.” Turbek cautions that this doesn’t necessarily mean that the future of the San Diego flycatchers is rosy. “Given the unprecedented rate at which environmental conditions are changing, I think this rate of adaptation is likely insufficient, and current records show that the San Diego population is still declining,” she says. But, she admits, it’s “encouraging.” Losing What Matters Scientists call this exchange of genes between populations “gene flow.” Gene flow has also helped boost the genetic diversity of another threatened California bird population — but at a cost. Phred Benham, now a postdoctoral researcher at UC Berkeley, spent his time as a Ph.D. student investigating how two savannah sparrow subspecies, Passerculus sandwichensis alaudinus and Passerculus sandwichensis beldingi, have colonized coastal saltmarshes and adapted to life in a saline environment. “While spending a lot of time driving around California, I became interested in the human impact on these marshes,” he says. Photo: Peter Pearsall/U.S. Fish and Wildlife Service He led a study published in January that documented how the genomes of California’s coastal savannah sparrows have changed over the past century — a period during which up to 90% of the birds’ habitat has been destroyed by human activity. Like Turbek, he sequenced the genomes of historical bird specimens preserved in natural history museums and compared them to those of birds alive today. Benham’s study encompassed six tidal marsh populations, and he expected that those that had lost the most habitat would also have lost the most genetic diversity. Instead, he and his colleagues found, in the San Francisco Bay area — where birds had experienced the greatest levels of habitat loss — genetic diversity remained relatively high. This, Benham believes, is probably due to immigration from inland populations of savannah sparrows. There’s just one problem: Those inland birds don’t share the genetic adaptations that make the coastal birds so perfectly suited for life in saltmarshes. Coastal sparrows have larger kidneys, the ability to excrete salt in their urine, and even the ability to distinguish between more- and less-salty water when they need a drink. Now genes from inland interlopers may be diluting the traits that make saltmarsh birds unique. There’s no way to really stop birds from other parts of the state from dispersing into these coastal areas, so Benham would rather focus on preserving and restoring saltmarsh habitat. “The population can tolerate immigrants if the selection [for salt-tolerant traits] is stronger than the rate of gene flow from those immigrants,” he says. In other words, if there’s enough intact saltmarsh habitat for salt-tolerant traits to really have a big impact on the birds’ success, genes from inland immigrants will be naturally weeded out. Genetics Reveal Conservation Priorities Taken together, these two studies illustrate the hidden ways in which environmental change can rewrite animals’ genetic code, and how the same unseen force — in this case, gene flow — can be helpful or harmful, depending on the context. According to Benham, wildlife managers’ views on gene flow have swung back and forth over time. In some cases, conservationists have pushed to eliminate “hybrid” populations, where subspecies have interbred, to preserve genetic purity. On the opposite side of the spectrum, wildlife officials famously brought cougars to Florida from other parts of North America to revive the state’s inbred population. “There’s a lot of evidence showing that when you have a very tiny, inbred population, gene flow can rescue it from the negative effects of inbreeding,” Benham says. But if intermingling populations are adapted for very different environments, the cure may be as bad as the disease. Both studies also highlight the value of natural history collections, an invaluable but underfunded and underappreciated resource for understanding environmental change. Duke University, for example, recently announced that it will close its herbarium, which houses 825,000 plant specimens dating back a century. “I don’t think we can fully grasp at this point the value of all those specimens in museum collections,” says Turbek. “We’re going to continue uncovering that as the technology develops to fully mine them for further information.” It’s too soon to say for sure how these newly revealed genetic-level changes might ultimately affect the health of San Diego’s willow flycatchers or San Francisco’s savannah sparrows. Researchers still lack the data necessary to connect the genetics to the physical traits of individual birds, or to say how those traits might impact their survival. But as climate change continues to accelerate, understanding how it may rewrite the genetic code of the species it impacts will only become more crucial. “Our understanding of [genetic] adaptation to changing climate conditions is surprisingly limited,” says Turbek. We’ll need every resource we have — from historical specimens in the back rooms of natural history museums to cutting-edge gene sequencing techniques — if we hope to untangle these complex relationships in the future. The answers we find may provide the clues we need to keep species from suffering in a world that’s changing around them. Get more from The Revelator. Subscribe to our newsletter, or follow us on Facebook and LinkedIn.  Previously in The Revelator: A New Way to Count African Forest Elephants: DNA From Dung The post Environmental Change, Written in the DNA of Birds appeared first on The Revelator.

A highway in Indiana could one day charge your EV while you’re driving it

Construction of the pilot project on U.S. Highway 52 began this month. State officials hope it can help quell range anxiety and electrify long-haul trucks.

This story was originally published by Inside Climate News and is reproduced here as part of the Climate Desk collaboration. Blake Dollier spoke excitedly as he watched the construction crews pulverize concrete along a quarter-mile stretch of U.S. Highway 52 where it passes through West Lafayette, Indiana. Soon, the Indiana Department of Transportation, or INDOT, where Dollier works as the public relations director, will install a series of copper coils under the highway’s surface to test a new technology Purdue University researchers developed that can provide power to electric vehicles wirelessly as they drive past. “Wouldn’t it really be something if we could just drive over the road and catch your charge for your vehicle as you drive across it?” Dollier said during a phone interview, watching the progress from the parking lot of one of the department’s satellite offices in West Lafayette. The state began construction of its new pilot project this month, and officials say they believe it could spur greater adoption of EVs and redefine the way people think about them. The project, they said, which is being done in partnership with Purdue and the engine manufacturer Cummins Inc., will be capable of providing power to vehicles even as they cruise by at speeds of up to 65 miles per hour. Ultimately, Purdue researchers and state officials hope the project will open up EVs to a wider customer base, largely by reducing battery costs and quelling concerns over range anxiety — the fear that an electric vehicle will run out of juice before reaching its destination. One in four U.S adults say that they would seriously consider buying an EV for their next purchase, but more than half of those who don’t want to buy an electric vehicle blame range anxiety, according to a survey conducted by AAA last year. Purdue professor John Haddock and graduate student Oscar Moncada examine a slab of concrete pavement they tested to handle heavy truckloads with wireless power-transfer technology installed below the surface. Courtesy of Consensus Digital Media While Indiana’s project wouldn’t be the first “dynamic EV charger” in the nation — Detroit installed a similar pilot project on a residential road last fall — it would be the first time the technology was installed on a highway. If successful, the technology could also help to electrify long-haul trucks, which are among the most difficult vehicles to decarbonize, said Nadia Gkritza, a civil engineering professor at Purdue University and the project’s lead researcher.  That’s because heavy-duty trucks would require significantly larger batteries due to their size, weight and the long distances they tend to travel, Gkritza said. However, she said, if they could receive power as they drive, it would allow those vehicles to carry smaller batteries, lowering overall costs and reducing the number of stops to recharge. “Really the possibilities are endless,” INDOT’s Dollier said. “And we’re just hopeful that this is something that can really benefit a lot of people here in the state of Indiana and maybe even across the country going forward.” INDOT says the pilot project should be complete by next summer, though private vehicles won’t be able to use it — at least not yet. Cars and trucks must be equipped with special receivers for the wireless charging to work, meaning current models are incompatible. The coils are installed underground and use magnetic fields to deliver the electricity wirelessly. Each coil only activates when a receiver is above it, Purdue researchers say, so the infrastructure won’t pose a threat to pedestrians, animals or other vehicles. Kaylee Dann, executive director of Greater Indiana Clean Cities, a clean energy advocacy nonprofit that isn’t involved with the project, agrees that the new technology could spur greater EV adoption in Indiana and nationwide. In fact, she said, the project is coming at a time when more and more Hoosiers are choosing to go electric. While Indiana’s overall EV adoption rates still pale in comparison to California and other leaders in the EV market, the state saw an astounding 1,200 percent increase in registered electric vehicles between 2016 and 2022, according to a state report published last year. Some 24,000 electric vehicles were registered in Indiana last year alone, according to the state’s Office of Energy Development. Dann believes that leaning into EVs has been a smart financial move by the state as the nation pivots to cleaner transportation options. Two recent federal policies — the 2022 Inflation Reduction Act and the Environmental Protection Agency’s new tailpipe pollution standards, finalized last month — are expected to dramatically increase domestic production of EVs nationwide in the coming years. Inside Climate News Indiana is already experiencing some of that economic gain. According to a state report published last September, Indiana has received about $8.2 billion in investments related to EV production since 2021. Those include a $3 billion investment by General Motors and Samsung to manufacture EV batteries in the city of New Carlisle and an $803 million investment by Toyota to expand its EV production in the city of Princeton. “We’ve seen a lot of investment from manufacturers,” Dann said. “So we’re gonna see a big influx of EVs being produced in the state.” But the biggest benefits to the state could be environmental. In its annual State of the Air Report, the American Lung Association ranked the Indianapolis metro area the 10th worst city in the nation for year-round particulate matter pollution known as PM2.5. Regular exposure to PM2.5, which is produced any time something combusts, has been linked to increased health risks, including greater risk of asthma attacks, cardiovascular and lung diseases and even premature death.  Because EVs draw power from batteries, not from burning fuel, a higher adoption of them would lead to better air quality for any state. Gkritza said that reducing air pollution is one of the broader goals of Indiana’s pilot project. “Greenhouse gas emissions, air quality, these are really bad across those freight corridors, transit corridors — we have communities that are negatively impacted by freight movement,” she said. More EVs also means fewer greenhouse gas emissions, Dann said, which helps to slow climate change. Transportation is America’s largest source of greenhouse gas emissions, according to the EPA, making up nearly a third of the country’s carbon footprint. In Indiana alone, EVs contribute 60 percent less carbon pollution than their fossil fuel counterparts, Dann said, despite the fact that the state’s electricity — the fuel for EVs — is predominantly produced by coal-fired power plants. More than half of the state’s electricity in 2021 was generated by coal, according to the Indiana Department of Environmental Management.  Having strong EV charging infrastructure in Indiana could be a boon nationwide, given the state’s centralized location in the U.S.  Indiana has more interstate highways passing through it than any other state, Indiana Governor Eric Holcomb touted in a 2021 report. It’s also home to the nation’s second largest FedEx hub and 41 freight railroads, he added, noting Indiana’s motto of being the “Crossroads of America.” “Simply put,” Holcomb wrote, “the world moves through Indiana.” This story was originally published by Grist with the headline A highway in Indiana could one day charge your EV while you’re driving it on Apr 27, 2024.

A New Declaration of Animal Consciousness

A group of prominent scientists believes fruit flies, fish, and mollusks might experience pain and pleasure.

This article was originally published by Quanta Magazine.In 2022, researchers at the Bee Sensory and Behavioral Ecology Lab at Queen Mary University of London observed bumblebees doing something remarkable: The diminutive, fuzzy creatures were engaging in activity that could only be described as play. Given small wooden balls, the bees pushed them around and rotated them. The behavior had no obvious connection to mating or survival, nor was it rewarded by the scientists. It was, apparently, just for fun.The study on playful bees is part of a body of research that a group of prominent scholars of animal minds cited earlier this month, buttressing a new declaration that extends scientific support for consciousness to a wider suite of animals than has been formally acknowledged before. For decades, there’s been a broad agreement among scientists that animals similar to us—the great apes, for example—may well have conscious experience, even if their consciousness differs from our own. In recent years, however, researchers have begun to acknowledge that consciousness may also be widespread among animals that are very different from us, including invertebrates with completely different and far simpler nervous systems.The new declaration, signed by biologists and philosophers, formally embraces that view. It reads, in part: “The empirical evidence indicates at least a realistic possibility of conscious experience in all vertebrates (including all reptiles, amphibians, and fishes) and many invertebrates (including, at minimum, cephalopod mollusks, decapod crustaceans, and insects).” Inspired by recent research findings that describe complex cognitive behaviors in these and other animals, the document could represent the beginnings of a new consensus and suggests that researchers may have overestimated the degree of neural complexity required for consciousness.The four-paragraph New York Declaration on Animal Consciousness was unveiled on April 19 at a one-day conference called The Emerging Science of Animal Consciousness being held at New York University. Spearheaded by the philosopher and cognitive scientist Kristin Andrews of York University in Ontario, the philosopher and environmental scientist Jeff Sebo of NYU, and the philosopher Jonathan Birch of the London School of Economics and Political Science, the declaration has so far been signed by 88 researchers, including the psychologists Nicola Clayton and Irene Pepperberg, the neuroscientists Anil Seth and Christof Koch, the zoologist Lars Chittka, and the philosophers David Chalmers and Peter Godfrey-Smith.[Read: Do animals have feelings?]The declaration focuses on the most basic kind of consciousness, known as phenomenal consciousness. Roughly put, if a creature has phenomenal consciousness, then it is “like something” to be that creature—an idea enunciated by the philosopher Thomas Nagel in his influential 1974 essay, “What Is It Like to Be a Bat?” Even if a creature is very different from us, Nagel wrote, “fundamentally an organism has conscious mental states if and only if there is something that it is like to be that organism … We may call this the subjective character of experience.” If a creature is phenomenally conscious, it may have the capacity to experience feelings such as pain, pleasure, and hunger, but not necessarily more complex mental states such as self-awareness.“I hope the declaration [draws] greater attention to the issues of nonhuman consciousness, and to the ethical challenges that accompany the possibility of conscious experiences far beyond the human,” Seth, a neuroscientist at the University of Sussex, wrote in an email. “I hope it sparks discussion, informs policy and practice in animal welfare, and galvanizes an understanding and appreciation that we have much more in common with other animals than we do with things like ChatGPT.”The declaration began to take shape last fall, following conversations among Sebo, Andrews, and Birch. “The three of us were talking about how much has happened over the past 10 years, the past 15 years, in the science of animal consciousness,” Sebo recalls. Scientists now believe, for example, that octopuses feel pain and cuttlefish remember details of specific past events. Studies in fish have found that cleaner wrasse appear to pass a version of the “mirror test,” which some researchers say indicates a degree of self-recognition, and that zebrafish show signs of curiosity. In the insect world, bees show apparent play behavior, while Drosophila fruit flies have distinct sleep patterns that might be influenced by their social environment. Meanwhile, crayfish display anxiety-like states—and those states can be altered by anti-anxiety drugs.These and other signs of conscious states in animals that had long been considered less than conscious excited and challenged biologists, cognitive scientists, and philosophers of mind. “A lot of people have now accepted for a while that, for example, mammals and birds are either conscious or very likely to be conscious, but less attention has been paid to other vertebrate and especially invertebrate taxa,” Sebo says. In conversations and at meetings, experts largely agreed that these animals must have consciousness. However, this newly formed consensus wasn’t being communicated to the wider public, including other scientists and policy makers. So the three researchers decided to draft a clear, concise statement and circulate it among their colleagues for endorsement. The declaration is not meant to be comprehensive but rather “to point to where we think the field is now and where the field is headed,” Sebo says.The new declaration updates the most recent effort to establish scientific consensus on animal consciousness. In 2012, researchers published the Cambridge Declaration on Consciousness, which said that an array of nonhuman animals, including but not limited to mammals and birds, have “the capacity to exhibit intentional behaviors” and that “humans are not unique in possessing the neurological substrates that generate consciousness.”The new declaration expands the scope of its predecessor and is also worded more carefully, Seth wrote. “It doesn’t try to do science by diktat, but rather emphasizes what we should take seriously regarding animal consciousness and the relevant ethics given the evidence and theories that we have.” He wrote that he is “not in favor of avalanches of open letters and the like,” but that he ultimately “came to the conclusion that this declaration was very much worth supporting.”Godfrey-Smith, a philosopher of science at the University of Sydney who has worked extensively with octopuses, believes that the complex behaviors those creatures exhibit—including problem-solving, tool use, and play behavior—can be interpreted only as indicators of consciousness. “They’ve got this attentive engagement with things, with us, and with novel objects that makes it very hard not to think that there’s quite a lot going on inside them,” he says. He notes that recent papers looking at pain and dreamlike states in octopuses and cuttlefish “point in the same direction … toward experience as being a real part of their lives.”Although many of the animals mentioned in the declaration have brains and nervous systems that are very different from those of humans, the researchers say that this needn’t be a barrier to consciousness. For example, a bee’s brain contains only about 1 million neurons, compared with some 86 billion in the case of humans. But each of those bee neurons may be as structurally complex as an oak tree. The network of connections they form is also incredibly dense. The nervous system of an octopus, by contrast, is complex in other ways. Its organization is highly distributed rather than centralized; a severed arm can exhibit many of the behaviors of the intact animal.The upshot, Andrews says, is that “we might not need nearly as much equipment as we thought we did” to achieve consciousness. She notes, for example, that even a cerebral cortex—the outer layer of the mammalian brain, which is believed to play a role in attention, perception, memory, and other key aspects of consciousness—may not be necessary for the simpler phenomenal consciousness targeted in the declaration.“There was a big debate about whether fish are conscious, and a lot of that had to do with them lacking the brain structures that we see in mammals,” she says. “But when you look at birds and reptiles and amphibians, they have very different brain structures and different evolutionary pressures—and yet some of those brain structures, we’re finding, are doing the same kind of work that a cerebral cortex does in humans.”Godfrey-Smith agrees, noting that behaviors indicative of consciousness “can exist in an architecture that looks completely alien to vertebrate or human architecture.”Although the declaration has implications for the treatment of animals, and especially for the prevention of animal suffering, Sebo notes that the focus should go beyond pain. It’s not enough for people to prevent animals in captivity from experiencing bodily pain and discomfort, he says. “We also have to provide them with the kinds of enrichment and opportunities that allow them to express their instincts and explore their environments and engage in social systems and otherwise be the kinds of complex agents they are.”[Read: The mirror test is broken]But the consequences of bestowing the label of “conscious” onto a wider array of animals—particularly animals whose interests we are not used to considering—are not straightforward. For example, our relationship with insects may be “inevitably a somewhat antagonistic one,” Godfrey-Smith says. Some pests eat crops, and mosquitoes can carry diseases. “The idea that we could just sort of make peace with the mosquitoes—it’s a very different thought than the idea that we could make peace with fish and octopuses,” he says.Similarly, little attention is given to the well-being of insects such as Drosophila, which are widely used in biology research. “We think about the welfare of livestock and of mice in research, but we never think about the welfare of the insects,” says Matilda Gibbons, who researches the neural basis of consciousness at the University of Pennsylvania and has signed the declaration.Although scientific bodies have created some standards for the treatment of lab mice, it’s not clear if today’s declaration will lead to new standards for the treatment of insects. But new scientific findings do sometimes spark new policies. Britain, for example, enacted legislation to increase protection for octopuses, crabs, and lobsters after a London School of Economics report indicated that those animals can experience pain, distress, or harm.Although the declaration makes no mention of artificial intelligence, the issue of possible AI consciousness has been on the minds of animal-consciousness researchers. “Current AI systems are very unlikely to be conscious,” Sebo says. However, what he’s learned about animal minds “does give me pause and makes me want to approach the topic with caution and humility.”Andrews hopes that the declaration will spark more research into animals that have often been overlooked, a move that has the potential to further expand our awareness of the scope of consciousness in the animal world. “All these nematode worms and fruit flies that are in almost every university—study consciousness in them,” she says. “You already have them. Somebody in your lab is going to need a project. Make that project a consciousness project. Imagine that!”

Egg labels, egg-splained: from cage-free to free-range, how to eat ethically and economically

Egg cartons are labeled with all sorts of descriptors, making grocery shopping a confusing experience. Experts tell us what these labels mean and how to shopShopping for eggs at the grocery store can be a confusing experience. Cartons are labeled with all kinds of descriptors – natural, organic, cage-free, free-range – and some cost more at checkout. But what do they actually mean, and for ethically minded consumers, are they actually worth the money?Protein-packed eggs are linked to relatively low carbon emissions compared with other land-based animal protein sources, but not all eggs are created equal when it comes to the environment, health or animal welfare, experts say. Continue reading...

Shopping for eggs at the grocery store can be a confusing experience. Cartons are labeled with all kinds of descriptors – natural, organic, cage-free, free-range – and some cost more at checkout. But what do they actually mean, and for ethically minded consumers, are they actually worth the money?Protein-packed eggs are linked to relatively low carbon emissions compared with other land-based animal protein sources, but not all eggs are created equal when it comes to the environment, health or animal welfare, experts say.“When it comes to ensuring better lives for laying hens, consumers have a lot of power, as long as they’re not led astray by meaningless labels,” said Daisy Freund, vice-president of farm animal welfare at the American Society for the Prevention of Cruelty to Animals, or ASPCA.The Guardian spoke with several experts, who explained what these egg labels mean, and how to shop in a way that balances a concern for hens with what’s good for the planet and your own wallet.What exactly do different egg labels mean?Grade AA, A or BGrade AA eggs are considered the best, and have ‘thick and firm’ whites. Illustration: Olivia de Salve Villedieu/The GuardianConsumer grades rate the interior quality of the egg yolk and white, as well as the appearance and condition of the shell. Grade AA eggs are considered the best, and have “thick and firm” whites, according to the US Department of Agriculture, or USDA, with yolks that are high, round and practically free from defects, with clean, unbroken shells. Grade A eggs are similar to Grade AA eggs but with less firm whites.Grade B eggs tend to have thinner whites and wider yolks. Their shells are also unbroken, but may show light stains. These eggs are rarely found in retail stores because they are often used to make liquid, frozen and dried egg products.Cage-freeEggs labeled “USDA-grade cage-free” are from hens that are able to roam vertically and horizontally in indoor houses. They must have access to fresh food and water, litter and protection from predators. These systems vary from farm to farm, but they must allow hens to exhibit natural behaviors and include scratch areas, perches and nests.In the last 10 years, hundreds of companies have committed to going entirely cage-free, and the country’s cage-free egg-laying flock increased by more than 10.5m hens in the first six months of 2023.But it’s important to remember that cage-free does not equal cruelty-free. “Cage-free means the bird lives indoors, but not in a cage,” said Carolyn Dimitri, director of NYU’s graduate food studies program. “This bird probably lives in crowded conditions.”Hormone-freeNo hormones are used in the raising of chickens. In fact, federal regulations banned their use in the 1950s, so if you see labels that say “no hormones”, it’s simply a marketing tactic and is not related to more humane treatment of hens or the health of an egg.Certified organicCertified organic eggs come from uncaged organic hens, which are fed organic feed free of animal byproducts, GMO crops or synthetic fertilizers, pesticides or herbicides. Regulated, certified and inspected by the USDA, organic flocks must have access to outdoor spaces and be raised without growth hormones (as all chickens, even non-organic ones, are) or antibiotics.But the organic label hasn’t always met consumer expectations for animal welfare, since organic layer hens still often live in crowded conditions. Some producers confine their hens to barns with concrete porches instead of true outdoor space. A new rule, however, mandates indoor and outdoor space requirements, thanks to the efforts of advocacy groups. But it doesn’t go into effect until 2029, said Freund, “so in the meantime, consumers should still seek out welfare-certified options”. The Cornucopia Institute, a non-profit food and farm watchdog group, maintains a score card to help consumers decide which organic eggs are best.Free-rangeRegulated by the USDA, free-range eggs are produced by hens that are able to roam vertically and horizontally in indoor houses, have access to fresh food and water and continuous access to the outdoors during their laying cycle. The outdoor area may be fenced and/or covered with netting-like material.Like cage-free hens, free-range hens must be allowed to exhibit natural behaviors and include scratch areas, perches and nests and have access to litter, have protection from predators and be able to move in the barn. Animal welfare advocates say free-range is a loosely defined term and since the type of outdoor space can vary, the label may fall short of shoppers’ expectations.Certified humaneNot affiliated with the USDA, Certified Humane is a project of Humane Farm Animal Care, a third-party non-profit certification program. The Certified Humane label means the hens’ environment takes into account their welfare needs and protects them from physical and thermal discomfort, fear and distress and allows them to perform their natural behavior. No cages or aviary systems that confine birds are allowed and laying hens must be provided with nest boxes.Pasture-raisedHens raised entirely on pasture can eat bugs, worms and grass and have ample room to roam, scratch, dust-bathe and engage in all of their natural behaviors. Since the term “pasture-raised” has no legal definition and is not regulated by the USDA, consumers should look for eggs that have additional labels and certifications to ensure the term is not misused by producers. Once considered a luxury item, rising demand helped shrink the price gap and increase supply. Pasture-raised eggs can be richer in flavor and more nutritious than caged eggs since the hens spend time outdoors and eat a more diverse diet. When hens have access to natural forage, the need for large-scale feed production and transportation is reduced, which results in fewer emissions compared to conventional egg production.What if a carton of eggs has none of these labels?The majority of the 300m chickens involved in egg production in the US are still raised in long, windowless sheds in rows of stacked battery cages. These caged hens are afforded only 67 sq ins of space on average – smaller than a sheet of letter-sized paper – and denied natural behaviors such as nesting, perching and dust-bathing. Factory-farmed eggs are often advertised as being “natural” or using “no antibiotics ever” and their cartons can paint misleading scenes of humane treatment on idyllic farms. If these cartons are not labeled as being “cage-free”, “free-range”, “organic” or “pasture-raised”, you can assume they came from factory farm hens who are confined to such a degree that they can’t even flap their wings.How do I eat ethically without breaking the bank?While eggs are still one of the cheapest forms of animal protein, prices have soared in recent years, now sometimes exceeding $1 per egg. “Higher-welfare animal products sometimes do cost more because farmers are investing in better conditions and treatment, as opposed to factory farming, which relies on cruel practices and externalized costs to make a cheap product,” said Freund. Since brands commonly charge more for claims such as “humane”, “natural” and even “free-range”, which are not backed by strong definitions or on-farm audits, shoppers can be easily misled.Experts suggest buying higher-welfare eggs like pasture-raised for special meals or reducing the number of eggs you eat each week. Another option is to supplement your diet with plant-based options. The ASPCA’s Shop with Your Heart Grocery List allows shoppers to find the lowest-cost, highest-welfare products.How do I know what kinds of eggs restaurants are using?The short answer is, you often don’t. While some restaurants may disclose what kinds of eggs they use for egg-centric dishes on a menu, it’s harder to know what types of eggs are featured in items such as baked goods, pastas, dressings and desserts. In 2018, Panera petitioned the FDA to know what an “egg” was exactly, stating that many of its competitors sell egg patties that contain more than five ingredients.McDonald’s recently announced they’re using 100% cage-free eggs, and Panera has committed to sourcing 100% cage-free eggs across all products by the end of 2025. Many restaurants use frozen, refrigerated liquid and dried forms of eggs whether they’re cage-free or not. The best way to find out is to ask the restaurants you patronize, but that doesn’t always mean you’ll get a clear answer.Are eggs from the farmers’ market automatically good?Farmers market eggs are richer in color and taste. Illustration: Olivia de Salve Villedieu/The GuardianFarmers’ markets can be great places to find alternatives to factory-farmed food. The yolks of farm-fresh eggs are often richer in color and taste since their food sources are of a higher quality than factory-farm chickens. Of course, not all farmers’ markets are created equal and just because a product is local doesn’t necessarily mean it’s better. Ask the farmer for details on how their hens are raised since not all farms raise animals the same way.What about vegan alternatives?For people looking for plant-based alternatives, there are a host of options. Simply Eggless’s vegan eggs are made from lupin beans and are available as a liquid, patty, bite and omelet, while Crafty Counter’s hard-boiled WunderEggs are created from cashews, almonds and other plant-based ingredients. For vegan baking, Bob’s Red Mill’s gluten-free Egg Replacer and Ener-G’s Egg Replacer are both made primarily from potato starch and tapioca flour, and Neat’s Egg Mixx is crafted from chia seeds and garbanzo beans.While vegan eggs that mimic the look, texture and taste of real eggs tend to be more expensive than eggs from hens, many of the flour-like products that replace eggs in baking are affordable (a 16oz bag can equal around 100 eggs). Experts say it’s critical for plant-based companies to scale up production and optimize ingredients so products can be competitively priced for consumers.The verdict: so what should I buy?When considering animal welfare, environmental impact and health, certified-organic, pasture-raised eggs are the winner.“The birds are able to live a free life that suits their biological needs, and they are not exposed to synthetic chemicals on the pasture or through their feed,” said NYU’s Dimitri. “This egg has the best animal-welfare and environmental lifestyle.” One study found that pasture-raised eggs had significantly more omega-3 fats and vitamin E compared to those from caged hens.When looking solely at animal welfare, experts point to eggs from hens raised on pasture as the best option. “Shoppers should look for eggs from farms that are certified by the Animal Welfare Approved program, which requires that animals are on pasture throughout their lives, or can look for the Certified Humane seal with the words ‘pasture-raised’ on the package,” said the ASPCA’s Freund.Even if shoppers can’t find one of these options, experts say most retail stores carry some Certified Humane products, even if they’re not pasture-raised. Those products at least ensure that animals are never in cages and are raised in enriched indoor spaces or have access to large outdoor spaces.

The end of coral reefs as we know them

Paige Vickers/Vox Years ago, scientists made a devastating prediction about the ocean. Now it’s unfolding. More than five years ago, the world’s top climate scientists made a frightening prediction: If the planet warms by 1.5 degrees Celsius, relative to preindustrial times, 70 to 90 percent of coral reefs globally would die off. At 2°C, that number jumps to more than 99 percent. These researchers were essentially describing the global collapse of an entire ecosystem driven by climate change. Warm ocean water causes corals — large colonies of tiny animals — to “bleach,” meaning they lose a kind of beneficial algae that lives within their bodies. That algae gives coral its color and much of its food, so bleached corals are white and starving. Starved coral is more likely to die. In not so great news, the planet is now approaching that 1.5°C mark. In 2023, the hottest year ever measured, the average global temperature was 1.52°C above the preindustrial average, as my colleague Umair Irfan reported. That doesn’t mean Earth has officially blown past this important threshold — typically, scientists measure these sorts of averages over decades, not years — but it’s a sign that we’re getting close. David Gray/AFP via Getty Images Marine biologist Anne Hoggett swims above bleached and dead coral on the Great Barrier Reef in April 2024. David Gray/AFP via Getty Images Tourists snorkel above a section of the Great Barrier Reef full of bleached and dead coral on April 5, 2024. So, it’s no surprise that coral reefs are, indeed, collapsing. Earlier this month, the National Oceanic and Atmospheric Administration (NOAA) announced that the planet is experiencing its fourth global “bleaching” event on record. Since early 2023, an enormous amount of coral in the Pacific, Atlantic, and Indian oceans has turned ghostly white, including in places like the Great Barrier Reef and the Florida Keys. In some regions, a lot of the coral has already died. “What we are seeing now is essentially what scientists have been predicting was going to happen for more than 25 years,” Derek Manzello, a marine scientist at NOAA who leads the agency’s coral bleaching project, told Vox. The recent extreme ocean warming can’t solely be attributed to climate change, Manzello added; El Niño and even a volcanic eruption have supercharged temperatures. But coral reefs were collapsing well before the current bleaching crisis. A study published in 2021 estimated that coral “has declined by half” since the mid-20th century. In some places, like the Florida Keys, nearly 90 percent of the live corals have been lost. Past bleaching events are one source of destruction, as are other threats linked to climate change, including ocean acidification. The past and current state of corals raises an important but challenging question: If the planet continues to warm, is there a future for these iconic ecosystems? What’s become increasingly clear is that climate change doesn’t just deal a temporary blow to these animals — it will bring about the end of reefs as we know them. Will there be coral reefs 100 years from now? In the next few decades, a lot of coral will die — that’s pretty much a given. And to be clear, this reality is absolutely devastating. Regardless of whether snorkeling is your thing, reefs are essential to human well-being: Coral reefs dampen waves that hit the shore, support commercial fisheries, and drive coastal tourism around the world. They’re also home to an incredible diversity of life that inspires wonder. “I’m pretty sure that we will not see the large surface area of current reefs surviving into the future,” said Hans-Otto Pörtner, who was involved in the landmark 2018 report, led by the Intergovernmental Panel on Climate Change (IPCC), that predicted the downfall of tropical reefs at 1.5°C warming. “Every year is going to be worse.” NOAA A map of coral bleaching “alerts,” which indicate where the ocean is unusually warm and bleaching is likely to occur. Red areas have a risk of reef-wide bleaching; magenta and purple regions are at risk of coral death. But even as many corals die, reefs won’t exactly disappear. The 3D formation of a typical reef is made of hard corals that produce a skeleton-like structure. When the polyps die, they leave their skeletons behind. Animals that eat live coral, such as butterfly fish and certain marine snails, will likely vanish; plenty of other fish and crabs will stick around because they can hide among those skeletons. Algae will dominate on ailing reefs, as will “weedy” kinds of coral, like sea fans, that don’t typically build the reef’s structure. Simply put, dead reefs aren’t so much lifeless as they are home to a new community of less sensitive (and often more common) species. “Reefs in the future will look very different,” said Jean-Pierre Gattuso, a leading marine scientist who’s also involved with the IPCC. “Restoring coral reefs to what they were prior to mass bleaching events is impossible. That is a fact.” On the timescale of decades, even much of the reef rubble will fade away, as there will be no (or few) live corals to build new skeletons and plenty of forces to erode the ones that remain. Remarkably, about 30 percent of the carbon dioxide that we pump into the atmosphere is absorbed by the oceans. When all that CO2 reacts with water, it makes the ocean more acidic, hastening the erosion of coral skeletons and other biological structures made of calcium carbonate. Jennifer Adler for Vox Bleached staghorn coral in a nursery run by the Coral Restoration Foundation off the coast of the Florida Keys in September 2023. Buying time For decades now, hard-working and passionate scientists have been trying to reverse this downward trend — in large part, by “planting” pieces of coral on damaged reefs. This practice is similar to planting saplings in a logged forest. In reef restoration, many scientists and environmental advocates see hope and a future for coral reefs. But these efforts come with one major limitation: If the oceans continue to grow hotter, many of those planted corals will die too. Last fall, I dived a handful of reefs in the Florida Keys where thousands of pieces of elkhorn and staghorn — iconic, reef-building corals — had been planted. Nearly all of them were bleached, dead, or dying. “When are [we] going to stop pretending that coral reefs can be restored when sea temperatures continue to rise and spike at lethal levels?” Terry Hughes, one of the world’s leading coral reef ecologists, wrote on X. Ultimately, the only real solution is reducing carbon emissions. Period. Pretty much every marine scientist I’ve talked to agrees. “Without international cooperation to break our dependence on fossil fuels, coral bleaching events are only going to continue to increase in severity and frequency,” Manzello said. Echoing his concern, Pörtner said: “We really have no choice but to stop climate change.” Jennifer Adler for Vox A collection of bleached “planted” staghorn coral on a reef in Florida in September 2023. But in the meantime, other stuff can help. Planting pieces of coral can work if those corals are more tolerant to threats like extreme heat or disease. To that end, researchers are trying to breed more heat-resistant individuals or identify those that are naturally more tolerant to stress — not only heat, but disease. Even after extreme bleaching events, many corals survive, according to Jason Spadaro, a restoration expert at Florida’s Mote Marine Laboratory. (“Massive” corals, which look a bit like boulders, had high rates of survival following recent bleaching in Florida, Spadaro said.) Scientists also see an urgent need to curb other, non-climate related threats, like water pollution and intensive fishing. “To give corals the best possible chance, we need to reduce every other stressor impacting reefs that we can control,” Manzello told Vox. These efforts alone will not save reefs, but they’ll buy time, experts say, helping corals hold on until emissions fall. If those interventions work — and if countries step up their climate commitments — future generations will still get to experience at least some version of these majestic, life-sustaining ecosystems. This story appeared originally in Today, Explained, Vox’s flagship daily newsletter. Sign up here for future editions.