New solutions to feed livestock and reduce land use, pollution
Livestock is the single largest user of land resources in the world, as the land used for the production of feed represents almost 80 percent of our planet’s total agricultural land – according to the Food and Agricultural Organization of the United Nations. Beyond just land usage, production of these crops is a major contributor to global pollution, and is often tied to significant deforestation and biodiversity loss.
Unfortunately, as the world’s population grows – estimated to exceed 9 billion by 2050 – demand for livestock will only increase. But a possible solution to this large-scale problem may come in a small-scale form. A recent study in Environmental Science & Technology postulates that bacteria could be used to efficiently produce large amounts of microbial proteins, which may actually be able to replace some of the crops currently grown to feed livestock.
Microbial proteins were first produced on an industrial scale using methane in the 1970s. But with advances in technology and a growing demand, researchers Benjamin L. Bodirsky, Ilje Pikaar, and colleagues decided to analyze the long-term effects that incorporating microbial proteins may have on land use, greenhouse gas emissions, and reactive nitrogen pollution.
They performed this analysis using an advanced computer model to generate projected land-use and agricultural-production patterns. The researchers tested 48 different scenarios, which suggest that by 2050, microbial proteins produced using hydrogen and other gas feedstocks could replace 175 to 307 million tons of crop-based animal feed annually, or as much as 10 to 19 percent of conventional crop-based livestock feed protein demand.
In their study, the researchers state that this move to microbial proteins is capable of having a significant global impact. In replacing just 13 percent of the protein in feed with microbial proteins, their results project that worldwide cropland usage could be reduced by 6 percent, global nitrogen losses from croplands by 8 percent, and agricultural greenhouse gas emissions by 7 percent. Overall, it appears that pushing for microbial proteins in livestock feed would be a wise move if we want to slow down our destruction of this planet.
Same sparrow songs have been passed down for hundreds of years
Researchers at Duke University have found a species of birds that has a tradition of passing songs down from one generation to the next. According to the experts, the time-honored songs of swamp sparrows are as long-lasting as some human traditions.
The team found that the species’ songs have been passed along for hundreds of years, and some songs date back even further.
Study first author Robert Lachlan is a professor of Psychology at Queen Mary University of London. “According to the models, some of the songs could go back as far as the Vikings,” said Lachlan.
Swamp sparrows can be found in the marshes and wetlands across eastern and central North America. The songs, which are comprised of two to five repetitive notes, are used by the sparrows to attract mates.
Decades back, scientists reported that swamp sparrows living in different places sing slightly different songs with varied numbers of patterns or notes. Young birds learn the local songs in the first weeks of life by imitating their elders.
Similar cultural traditions have been observed in a variety of other animals as well, but it has been commonly believed that human traditions are more likely to endure over time. The researchers set out to test this theory, and recorded the songs of 615 male swamp sparrows across New York, Pennsylvania, Michigan, and Wisconsin.
By measuring and analyzing each song with computer software, the scientists identified 160 types of songs across the bird populations. Each male was found to perform only a few specific songs.
The researchers developed a mathematical model that simulates how each new song type spreads within groups over time in order to establish how young sparrows decide which songs to learn as well as which birds to imitate.
The study revealed that young birds replicate the most popular songs that can be heard the most often, a phenomenon Lachlan referred to as a “conformist bias.”
In addition, the sparrows are very dedicated to imitating the songs accurately, and were found to match the notes and patterns of the songs 98 percent of the time.
The findings of the research demonstrate that the songs of swamp sparrows are not short-lived trends, but are faithfully handed down for generations. The researchers estimate that some song types have persisted among this species for at least 500 years.
Study co-author Stephen Nowicki is a professor of Biology at Duke.
“The longstanding stable traditions so characteristic of human behavior have often been ascribed to the high cognitive abilities of humans and our ancestors,” said Professor Nowicki. “But what we’re showing is that a relatively simple set of rules that these songbirds are capable of following can achieve equally lasting traditions.”
“We’re not saying that birds have anything akin to human culture,” said Lachlan. “It shows that just those two ingredients – a preference for popular songs, and the ability to copy them – can get you quite a long way to having stable complex culture.”
The study is published in the journal Nature Communications.
Image Credit: Robert Lachlan
Climate change will soon impact biodiversity more than land use
Biodiversity is crucial, not only for the health and success of an ecosystems’ food chain, but also for our understanding of how species interact and what factors drive population declines.
The term “biodiversity” refers to the number of different species in an ecosystem or environment. But habitat degradation from cities, infrastructure and agriculture have had a significant hand in reducing biodiversity in many areas.
Now, a new study shows that climate change will have an even greater impact on biodiversity than habitat degradation, and reptiles will be the hardest hit, more so than birds and mammals.
Researchers from the University of College London conducted the study which was published in the journal Royal Society Proceedings B.
Already, land use from agricultural operations and development has reduced biodiversity by over 10 percent. When species loss is more than 20 percent, it can significantly weaken an ecosystem and this is already estimated to have occurred in many areas across the globe.
The new study takes into account both land use and the projected impacts of climate change to see how biodiversity will be affected in the future.
The researchers found that by 2070, climate change could exceed land use in regards to its impact on vertebrates.
Climate change alone is predicted to cause one-tenth of all vertebrate communities to go extinct, but combined with land use, vertebrate biodiversity could decrease as much as 40 percent.
Future studies that examine biodiversity need to consider both land use and climate change in order to best predict species loss.
“This is the first piece of research looking at the combined effects of future climate and land use change on local vertebrate biodiversity across the whole of the land surface, which is essential when considering how to minimise human impact on the local environment at a global scale,” said Tim Newbold, an author of the study. “The results show how big a role climate change is set to play in decreasing levels of biodiversity in the next few decades and how certain animal groups and regions will be most affected.”
Polar bears can efficiently consume energy while walking
The polar bear stranded on an iceberg has become the synonymous with climate change, so much so that it could be considered the unofficial mascot.
Sea ice in the Arctic is thinning and melting leading to longer warmer seasons. For polar bears, who depend on this ice to travel and hunt, the thinning ice means more time swimming and walking to get food.
Polar bears are getting less and less food as climate change takes its hold which has many researchers concerned because of how much energy polar bears use while hunting.
Research from the 1970s and 1980s suggested that polar bears have to eat more food than other similarly sized animals to stay warm in their environment.
A new study, however, shows that actually polar bears are efficient travelers and consume the same amount of energy as grizzly bears and other large animals when they walk.
The results, published in the Journal of Experimental Biology, will help conservation and management efforts to ensure the survival of polar bears because they can now accurately estimate how much energy polar bears need to stay alive
First, the team trained bears to walk on a treadmill in an enclosed chamber. This allowed the researchers to measure how much oxygen the bears consumed while walking which could then be used to calculate energy use.
“Finding foods that the polar bears would be highly motivated to walk for was challenging,” said Terrie Williams, a co-author of the study.
The grizzly bears, on the other hand, had no problem adjusting to the treadmill.
“They just bowled right in; they did not care if the treadmill moved fast or slow, all they cared about were the training treats,” said William.
The researchers found that when walking at speeds up to 4.6 kilometers per hour, both the polar and grizzly bears consumed the same amount of energy, and this wasn’t any more than other large animals.
Polar bears also had similar metabolic rates to other large animals, and when the researchers observed and monitored wild polar bears in Alaska, the bears didn’t move any differently to the captive polar bears used in the study.
The results show that polar bears move efficiently while they walk, but with the encroaching threats from climate change, the results do not change the fact that polar bears are struggling to get enough food every year.
The secret language of dogs is revealed through their gestures
Experts at the University of Salford in Manchester have uncovered some of the hidden messages behind the body language of dogs. The researchers have identified 19 different gestures and have interpreted what the dogs are often requesting when they use these signals.
The team analyzed video footage of 37 dogs interacting with their owners on a daily basis. The study revealed that different dogs use different gestures to get the same message across. The researchers also found that dogs will use a variety of signals to make a request when the first gesture is not acknowledged.
The experts identified many different signals that indicate a dog is hungry including lifting a paw, licking, and jumping up and down. When asking to be scratched, a dog would roll over on his back or move its head forward in the direction of a person’s hand.
Standing on their hind legs indicated that the dogs wanted owners to play with them. The animals also asked their owners to play with a gentle chomp on the arm.
In order to request a toy, some dogs were seen rubbing their heads on an owner or an object. Other dogs indicated that they wanted a toy by lifting a single front paw and briefly touching a person or an object.
The most commonly-used signal recognized in the investigation was the “head turn,” which is when the dogs looked from a human to an object that they were interested in. In the video footage analyzed for the study, this object was usually a food dish.
The researchers determined that the head turn gesture suggests that dogs are “potentially adept at using referential communication.”
The study is published in the journal Animal Cognition.
Inland fishery harvests are drastically underreported
A new study found that inland fisheries are underreporting how many fish are caught and consumed each year.
The research shows that food reports and data meant to keep track of where the world’s food is going and coming from underestimates how much inland fisheries supply to low-income countries.
Fish are an important source of protein, however, researchers from the University of Wisconsin-Madison conducted a study to show that harvest reports from inland fisheries are unreliable and based on insufficient monitoring.
Every year, food production reports are sent to the Food And Agriculture Organization, a part of the United Nations, and these reports make up a large part of how we understand and track global food security.
Given the importance of accurate food reports for food security and preventing starvation and malnutrition, the study emphasizes the need for better harvest records of inland fisheries.
The results were published in the journal Proceedings of the National Academy of Sciences.
Part of the reason inland fisheries have a difficult time reporting accurate harvests is that the majority of fisheries are small-scale operations located in low-income countries.
Some of the fish harvested in these areas are for personal consumption and not sold which means that they are not reported to the UN.
“Subsistence fishers may not rely on fishing as their primary occupation for their livelihood and then they might consume some or all their catch within their household, so the fish never enters any formal value chain,” said Etienne Fluet-Chouinard, the lead author of the study.
To better understand the role inland fisheries play in local and global food chains, the researchers reviewed Household Consumption Expenditure Surveys which are conducted as a way to estimate living standards.
Data from over half a million surveys in 42 low and middle-income countries were considered for the study, and the researchers found that people were catching far more fish than was being reported every year.
The 42 countries were underestimating their harvests by 65 percent.
“Approximately one out of every three fish caught is not showing up in the national statistics,” said Fluet-Chouinard. “In a lot of those countries, the resource is important because it is an open-access resource, so even disenfranchised groups can tap it as a source of animal protein.
Fluet-Chouinard notes that it’s possible that nearly 200 million people are getting all their animal protein from rivers and lakes.
The results are extremely problematic because the Food And Agriculture Organization relies on reports to make decisions about management and sustainability, and if these fisheries become threatened, many people would lose their main source of protein.
Wild primates are under increasing pressure from human activities
Some of the world’s leading primate researchers have investigated the influence of human activities on wild primates. The team found that the natural habitats of primates could decline by up to 78 percent this century across regions where the animals are commonly found.
Land use changes such as deforestation are already forcing many primates out of their natural habitats, while hunting and the bushmeat trade have also led to shocking declines in primate populations.
The International Union for Conservation of Nature (IUCN) currently lists 439 primate species as being endangered, and 60 percent of those are facing the threat of extinction. The situation is particularly troubling in Indonesia and Madagascar, where 90 percent of the primate population has vanished and more than three-quarters of species are endangered.
Study co-author Christian Roos is a scientist in the Primate Genetics Laboratory at the German Primate Center (DPZ).
“The destruction of the natural environment through deforestation, the expansion of agricultural land and infrastructure development to transport goods has become a major problem,” said Roos.
“The main contributors of this development are the industrial nations. There is a high demand for raw materials such as soy, palm oil, rubber, hardwood or fossil fuel. The four primate-rich countries cover 50 percent of these export goods to China, India, the US and Europe.”
The research team analyzed the biggest threats to primates in four countries. In Brazil, Madagascar, and Indonesia they found that habitat loss is the biggest stressor for primates, while the biggest threat in the Democratic Republic of the Congo is the bushmeat trade.
The experts also used information from the United Nations and World Bank databases to estimate the spread of agricultural land over the rest of this century.
In the worst-case scenario, 78 percent of the primate habitats in Brazil, 72 percent in Indonesia, 62 percent in Madagascar, and 32 percent in the Congo will be gone by the year 2100.
The authors are calling for the expansion of protected areas, reforestation, and the planting of corridors as critical measures to preserve primate populations. In addition, the governments must work harder to combat illegal hunting, forest destruction, and primate trade.
“Primates are like canaries in a coal mine,” said Roos. “They are invaluable for tropical biodiversity as they are vital for the regeneration of forests and stable ecosystems. Their extinction will serve as an alarm bell for humans and an indication that these habitats will become unusable in the long run.”
The study is published in the journal PeerJ.
By Chrissy Sexton, Earth.com Staff Writer
Possibility of extinction looms for chimps, orangutans
When it comes to the primate family, humans aren’t sharing well with their cousins. Now, as the growing human population eats away at chimp, orangutan, and other non-human primate habitats, extinction looms for some species.
The majority of primate species – a full two-thirds – are found in just four countries around the world: Brazil, Indonesia, Madagascar and the Democratic Republic of the Congo. Sixty percent of them are facing the threat of extinction before the end of the century, a new study claims.
And as humans convert wild lands to agriculture, housing developments and other human uses, their habitat is shrinking and fragmenting. As a result, researchers said, non-human primate populations are in decline around the world.
“Many iconic species will be lost unless these countries, international organisations, consumer nations, and global citizens take immediate action to protect primate populations and their habitats,” Dr. Anna Nekaris of Oxford Brookes University told the Daily Mail.
They found that if the status quo doesn’t change, by 2100 the habitat for primates will have shrunk dramatically in all four countries – most drastically, by 78 percent in Brazil and 72 percent in Indonesia.
In short, without changes, extinction looms for humans’ closest cousins in those four countries.
Primate populations are small elsewhere. In Europe, for example, the only native population of wild monkeys is on the rock of Gibraltar.
Expanding protections of primate habitat in Brazil, Indonesia, Madagascar and the Congo is vital, but it’s not the only way humans can help their closest relatives on the evolutionary tree.
“People do not realise that in their daily lives, by consuming less and making more ecologically friendly consumer choices, such as reducing use of single use plastic and eating food grown locally, they can have direct impacts on tropical forests and the long-term sustainability of biodiversity,” Nekaris said.
The research has been published in the journal Peer J.
By Kyla Cathey, Earth.com staff writer
Sniffer bees show surprising potential in explosive detection
Bees could soon be used to detect explosives, as new research has found bees to be even more efficient than trained dogs at finding hazardous landmines.
Researches from St. Andrews University recently trained “sniffer bees” to detect TNT, and the bees were then able to find lost landmines in Croatia.
The study marks the first time that bees have been successful at such a feat even though attempts to train bees to find explosives have been going on since 2014.
Bees could potentially be used to detect millions of abandoned landmines around the world which are a threat to public safety. It’s estimated that old landmines kill or injure 15,000 to 20,000 people every year, according to the Daily Mail.
For this study, the bees found mines that were left over from Croatia’s fight for independence in 1991.
In order to train the bees to hone in on explosives, the researchers placed drops of sugar water on TNT in an effort to coax bees out of the hive and towards the explosives.
Apismellis Era Carnica honey bees were trained over two days to sniff out the TNT in hopes of getting the sugar treat.
“Basically we teach them by a version of reward like you do with dogs,” Ross Gillander, a member of the research team, told the Daily Mail. “The bees fly out of their hive to go about their normal day to day job of finding pollen but instead of finding pollen they find explosives. It’s the sugar syrup, which draws them out.”
The bees have to be retrained after three days because they soon lose interest in the TNT.
Once the bees were sent out to find explosives, Gillander helped design equipment that detected trace explosives on the bees, like pollen, when they returned to the hive.
When the bees returned, they went through a specialized material similar to canvas which the researchers then exposed to light. The light indicated if the bees had explosives on them when they went through the canvas.
Drones then followed the bees to find out where the honeybees picked up the trace explosives and a team was dispatched to clear the mine.
Bees can be trained to find explosives much faster than dogs, and even though the bees have to be retrained after three days, they can work longer than sniffer dogs and are able to go places that dogs can’t.
Given how successful the bees were at finding landmines in a real-world scenario, honeybees could soon be used to save lives and efficiently detect hazardous materials.
Sea urchins use their feet to see
Sea urchins are those spiny ball-shaped creatures found on the bottom of the ocean, and sometimes found on the bottom of feet if you’re unlucky enough to step on one. Those famous spine help protect them from predators, which is a useful trait if you are like the sea urchin and have no eyes. But despite their lack of eyes, these animals are still able to detect potential dangers – something that has intrigued researchers for years. In 2011, researchers discovered the sea urchins actually “see” with their feet. And now and new study has tested just how good their vision is.
A study from Lund University in Sweden has determined that sea urchins have tentacle ‘tube feet’ that are able to see well enough to fill their basic needs.
“Sea urchins are currently the only animals that have been shown to see without having eyes,” says researcher John Kirwan. “They see using light-sensitive cells in their tube feet, which resemble tentacles and, like the spines, are all over the body. You could say that the entire sea urchin is one single compound eye.”
The researchers studied long-spined urchins, giving them the equivalent of a human eye exam. This consisted of placing the urchins inside a lit-up cylinder that had dark images on the walls. “’Ordinarily, sea urchins move towards dark areas in order to seek cover,” says Kirwan. “When I notice that they react to certain sizes of images but not to others, I get a measurement of their visual activity.”
By showing the animals different figures against the wall, followed by dark shadows above them that resembled a predator, Kirwan was able to test their “sight.” He noted how large the figures had to be before the sea urchins would defend themselves by pointing their spines towards the looming shadow. The results showed that their vision is actually rather poor.
An object above the urchin needs to take up between 30 and 70 degrees of the 360 degrees surrounding the urchin in order for the animal to see it. Us humans only need an object to take up roughly 1/60th of a degree in order to detect it. “However, this is still sufficient for the animal’s needs and behavior,” explains Kirwan. “After all, it’s hardly poor eyesight for an animal with no eyes.”
Painted lady butterflies migrate over 7,400 miles each year
The painted lady butterfly makes the longest known migration of any butterfly to date, according to new research from the British Ecological Society.
Each year, painted lady butterflies travel over 7,450 miles and cross the Sahara Desert twice in the process as they migrate from Europe to Africa and then to the Mediterranean in early spring.
The Palearctic-African migratory circuit is unprecedented for butterflies, and because insect movement is difficult to track, researchers were unsure exactly how painted lady butterfly offspring made the journey.
“It is difficult to study the movement of insects by means of observations, marking, or radio tracking, since there are millions of individuals and they are very small,” said Gerard Talavera, leader of the research.
In order to better understand the full scope of painted lady butterfly migration, Talavera and a team of researchers first had to discover where the butterflies first developed as caterpillars.
The researchers pinpointed the natal origin of the butterflies by analyzing stable hydrogen isotopes from the wings of adult painted lady butterflies.
Stable hydrogen isotopes are geographic specific and can help researchers locate where the butterflies transformed from caterpillars to butterflies.
The researchers discovered that the butterflies seemed to stay in the Afrotropics over the winter and their offspring made the migration to the Mediterranean, starting the cycle all over again.
Painted lady butterflies travel over 12,000 kilometers every year between generations.
Climate change disrupting commercial fish migration and industry
Fish species are relocating at a pace that international fishing laws cannot keep up with, as climate change continues to warm the temperature of ocean waters. According to a new study from Rutgers University, this will cause increasing international conflict.
Study author Malin Pinsky is an assistant professor of Ecology, Evolution and Natural Resources in Rutgers-New Brunswick’s School of Environmental and Biological Sciences.
“Most people may not understand that the right to harvest particular species of fish is often decided by national and regional fisheries management bodies,” said Professor Pinsky. “Those bodies have made the rules based on the notion that particular fish species live in particular waters and don’t move much. Well, they’re moving now because climate change is warming ocean temperatures.”
The study has demonstrated for the first time that new fisheries are likely to appear in more than 70 countries all over the world as a result of global warming. Historically, a large migration of fish species has sparked disagreement among fishing communities.
Such conflict leads to overfishing and subsequently reduces the food, profit, and employment provided by fisheries. Disputes over newly-shared fisheries can also impact international relations beyond the coastline.
In a previous study, Professor Pinsky and Rutgers postdoctoral associate James Morley reported that many major commercial fish species could move their ranges hundreds of miles northward in search of colder water. This migration is already underway, and the results have been highly disruptive for fisheries.
“Consider flounder, which have already shifted their range 250 miles farther north,” said Professor Pinsky. “Federal fisheries rules have allocated many of those fish to fishers in North Carolina, and now they have to steam hundreds of extra miles to catch their flounder.”
The team pointed out examples of international disputes caused by the disruption of fisheries, including the “mackerel war” between Iceland and the European Union (EU).
Lobster fishers from the United States and Canada are clashing over the lobster fishery, which is moving north from New England to the Canadian Maritime Provinces.
The study authors explained that, while the migration of fish is inevitable with changing climate conditions, the conflicts can be avoided.
“We need international agreements for the collaborative monitoring and sharing of fisheries as they move, much as the Antarctic conservation agreement has begun to do,” said Professor Pinsky.
“We have a chance to avoid conflict over fisheries that could escalate international tensions, threaten our food supply, and reduce profit and employment worldwide. Avoiding fisheries conflicts and overfishing ultimately provides more fish, more food and more jobs for everyone.”
The study is published in the journal Science.
Image Credit: Malin Pinsky/Rutgers University-New Brunswick