The extinction of fanged kangaroos could save other species

A study from the University of Queensland may give new insight into the disappearance of ancient kangaroos. The researchers found evidence that an extinct species of kangaroos known as fanged kangaroos survived millions of years longer than previously thought.

Fanged kangaroos, also known as balbarids, were thought to have died out approximately 15 million years ago, but a new analysis reveals that fanged kangaroos were still around as recently as 10 million years ago. The research team used fossil evidence to investigate the various species of fanged kangaroos, their body size, and the timing of their extinction.

Kaylene Butler is a PhD student at the University of Queensland School of Earth and Environmental Sciences.

“Currently, we can only hypothesize as to why balbarids became extinct – the original hypothesis related to events during a change in climate 15 million years ago but the balbarids persisted past that,” said Butler. “This new finding of their persistence until 10 million years ago means something else must have been at play, such as being outcompeted by other species.”

The balbaroo fangaroo is an ancient balbarid which was found to be around the size of a wallaby. This fanged creature was identified from a fossilized skull found at the Riversleigh World Heritage Area in Northern Australia, which is also the origin of the fossils examined for the current study. These fossil deposits, which are held at the Queensland Museum, date back 25 million years.

“Fanged kangaroos and the potential ancestors of modern kangaroos are both browsers – meaning they ate leaves – and they scurried, but did not hop,” said Butler. “There is a lot of research to be done before we can be sure what their canine teeth were used for but some have suggested they were used to attract potential mates. We do know that despite their large canines they were herbivorous.”

The researchers determined that the fanged kangaroos increased in body size right up until they vanished. While their body mass was growing, however, the diversity of their species was shrinking.

Butler said the study may help experts establish a more detailed timeline of kangaroo evolution. Furthermore, understanding what caused the extinction of the fanged kangaroo species could help save other macropod species from vanishing forever.

“Currently 21 macropod species are listed as vulnerable or endangered on the International Union for the Conservation of Nature Red List of Threatened Species,” said Butler.

The research is published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.

By Chrissy Sexton, Earth.com Staff Writer

Scientists: whales and dolphins form human-like societies

Tightly knit families and groups of friends. Alliances toward specific goals. Teaching each other hunting techniques. If these sound like human behaviors to you, you’re not wrong – but they’re not. Whales and dolphins form human-like societies with complex relationships and culture, according to marine biologists.

In a new study, scientists found that Cetaceans generally have intricate societies complete with social play, transfer of knowledge, and even “dialects” in their vocal communication. Some of the whistles and chirps common in whale and dolphin song may even be names, the biologists said.

More complex societies appear to be linked to brain size in proportion to the whales’ or dolphins’ bodies, they said.

Humans have long known that whales and dolphins have elaborate cultures, said Dr. Susanne Shultz, an evolutionary biologist at the University of Manchester. But the insight into their behaviors and how they influence whales’ and dolphins’ human-like societies has added a new layer to the understanding of how intelligence evolves.

“That means the apparent co-evolution of brains, social structure, and behavioural richness of marine mammals provides a unique and striking parallel to the large brains and hyper-sociality of humans and other primates on land,” Shultz said. “Unfortunately, they won’t ever mimic our great metropolises and technologies because they didn’t evolve opposable thumbs.”

The team, from the University of Manchester, Stanford University, the London School of Economics and Political Science, and the University of British Columbia, gathered information about 90 different species of whales, dolphins and porpoises. With that information, they created a database documenting cooperative behaviors and other aspects of the Cetaceans’ social structures.

They used the datasets to test evolutionary hypotheses about the social brain and cultural brain, two ideas proposed to explain the evolution of human society and intelligence in other land mammals.

The team of researchers found that the theories appear to apply to marine mammals as well.

“This research isn’t just about looking at the intelligence of whales and dolphins; it also has important anthropological ramifications as well,” said Dr. Michael Muthukrishna of the London School of Economics and Political Science. “In order to move toward a more general theory of human behaviour, we need to understand what makes humans so different from other animals. And to do this, we need a control group. Compared to primates, cetaceans are a more ‘alien’ control group.”

The research may also offer clues into how certain behaviors crop up in some animals but not others – especially as Cetacean brain structures are not very similar to those of land mammals.

Those different brain structures led some scientists to theorize that dolphins and whales couldn’t develop higher cognitive skills, let alone human-like societies, said Dr. Kieran Fox of Stanford.

“I think our research shows that this is clearly not the case,” he said. “Instead, a new question emerges: How can very diverse patterns of brain structure in very different species nonetheless give rise to highly similar cognitive and social behaviors?”

The team’s study has been published in the journal Nature Ecology and Evolution.

By Kyla Cathey, Earth.com staff writer

Saving bats whose teeth are used as currency

A study from The Field Museum and the University of Queensland provides insight that could help protect flying fox fruit bats in the Solomon Islands. The flying foxes not only play a key role in the health of the ecosystem but are also important to local tradition.

“Island flying foxes are a diverse group of bats, and they’re nearly all in trouble. Many species are endangered or extinct from some islands,” said lead author Tyrone Lavery.

On many Pacific islands, hunting has dramatically reduced flying fox populations. Lavery learned about a custom on one of the Solomon Islands, Makira, where flying fox teeth are used as currency. He wanted to find out what impact this may have on hunting.

“Many island flying foxes are endangered, but the effects of using their teeth as currency hasn’t been studied before,” explained Lavery.

The research team surveyed 197 residents of Makira to learn about their use of flying fox teeth. The scientists wanted to try to gain a better understanding of how the teeth were being used, whether the teeth were a driving factor in hunting, and how hunters might play a role in conservation of the flying foxes.

“Doing this study was fun — people think you are crazy to be asking about bats,” said co-author John Fasi, who is originally from Makira. “They see how abundant the bats are in the wild and have no knowledge that they are threatened.”

As a result of the survey, the researchers learned that there are two types of flying foxes on Makira, the larger Pacific flying fox and the smaller Makira flying fox. They also discovered that people were more interested in hunting the larger bats. These bats have bigger teeth, but the primary reason the larger bats are more desirable is because they have more meat.

“It is becoming evident that modern currency is slowing taking over the use of traditional currency,”said Fasi. “However, we see that the use of bats as food is still going on. But conserving bats involves a number of fronts, like protecting their habitats, forests and mangroves, from destruction. Perhaps balancing between the number of bats killed for traditional practices and the need to conserve some will continue to keep the population of bats intact.”

Lavery explained that the significance of the study is its role in protecting flying foxes, which ultimately protect the island’s environment.

“The bats are hugely important for health of Makira’s whole ecosystem. The Pacific islands are exposed to hurricanes, which can destroy forests — fruit bats spread seeds that help forests regenerate.”

The research is published in the journal Oryx.

By Chrissy Sexton, Earth.com Staff Writer

Antarctic penguins face catastrophic loss of chicks

For the second time in three years, a colony of Antarctic penguins has suffered a tragic die-off of its chicks.

In 2015, the colony of about 36,000 Adelie penguins lost all of its chicks. So far this year, all but two of the baby penguins have died.

The culprit, experts believe, was late spring ice that forced the adult penguins to travel much farther for food.

According to the World Wildlife Fund, the Adelie penguin is the smallest and most widespread penguin species in Antarctica. Although they’re considered a species of “least concern” – meaning they’re not considered endangered or threatened – that could change in the future.

Like other Antarctic penguins, the Adelie colony faces the duel challenges of a changing climate and commercial fishing in their traditional feeding grounds.

In areas that have already begun to show the effects of climate change over the past 25 years, Adelie penguin populations have dropped by as much as 65 percent, the WWF reports.

The little penguins only breed on land that has no ice, which means that when ice extends farther than usual – as it did this year – adult penguins have to travel farther to find food for themselves and their chicks. In normal years, adults travel 30 to 75 miles to their fishing territory.

When commercial fishing operations move into that territory, that just means one more competitor for the Adelie penguins’ fish.

“The risk of opening up this area to exploratory krill fisheries, which would compete with the Adelie penguins for food as they recover from two catastrophic breeding failures in four years, is unthinkable,” Rod Downie, the WWF’s head of polar programs, told the BBC.

The WWF is calling for the creation of a Marine Protection Area at the fishing grounds near the colony.

In an opinion column about the tragic die-off of the penguin chicks printed in The Guardian, John Sauven, the director of Greenpeace, also called for a marine sanctuary for the colony.

“All of us who live on this planet are the guardians of these environments, not only to protect the wildlife that lives in them, but because the health of our oceans sustains our planet and the livelihoods of billions of people,” Sauven wrote.

By Kyla Cathey, Earth.com staff writer

Troublemaking turkeys are ruffling feathers in Boston

‘Tis the season for wild turkeys in Massachusetts, but one group of troublemaking turkeys have Boston residents in a “fowl” mood.

The indigenous bird was once completely eradicated from the state. Thanks to the hard work of wildlife restoration experts, the turkeys Ben Franklin once wanted to honor as America’s national bird have made a comeback.

That comeback hasn’t come without a cost. Gangs of wild urban turkeys have begun strutting around Boston like the own the place.

“There was a girl at church on Sunday who was telling me how she got chased. She and her dog got chased by a wild turkey,” Councilman Craig Kelly said during a recent Cambridge City Council meeting.

Over the past three years, Boston and its suburbs have received countless similar complaints, including that they damage cars, attack people and pets, and ruin gardens. A review of public records turned up 60 such reports last year alone, the Associated Press said.

One Cambridge meeting to discuss the turkey problem became an example itself. When the meeting ended, Councilman Dennis Carlone was rushed by a turkey as soon as he left.

“It was like the turkey was waiting for me,” he told the Boston Globe. “They’re clearly strategizing. And I agree, we have to think of some humane way to deal with this.”

In five cases, turkeys became so aggressive that police had to shoot them for public safety, the Associated Press reported.

The troublemaking turkeys aren’t just a problem in Boston. Cities throughout the U.S. have had to deal with more of the feathered fiends finding their way into urban areas.

And of course, they’re not alone. Other animals like raccoons, foxes and mountain lions have made appearances in cities in recent years. The Boston area has been swamed by rabbits as well as turkeys, and they do just as much damage to yards and gardens.

The problem is that wild animals become acclimated to human areas, but don’t abandon their normal, wild behaviors. Residents who leave food out for wildlife don’t help, because it encourages them to return to the area.

“Turkeys don’t really mean to harm people – it’s just tied to their social dynamics within the flock,” David Scarpitti told the Associated Press. Scarpitti is a wildlife biologist and turkey expert for the Massachusetts Department of Fish and Wildlife. “They lose perspective that humans are humans and turkeys are turkeys. They just want to assert dominance over anything.”

By Kyla Cathey, Earth.com staff writer

Clams and worms emit shockingly high amounts of methane

By now, it’s a well-known fact that cows are a major contributor of methane emissions in the atmosphere. But now, a surprising new study has found that clams and worms in the Baltic also emit vast quantities of methane, even comparable to that of 20,000 dairy cows.

The study was conducted by researchers from Cardiff University and Stockholm University and published in the journal Scientific Reports.

The researchers found that ocean clams and worms release methane and nitrous oxide from bacteria in their guts. The sheer amount of greenhouse gases emitted by these seemingly innocuous creatures has a far more significant impact on global climate change than previously considered.

“These small yet very abundant animals may play an important, but so far neglected, role in regulating the emissions of greenhouse gases in the sea,” said Dr. Stefano Bonaglia, the lead author from Stockholm University.

Methane is 28 times more harmful than carbon dioxide in terms of warming potential, which is why methane emissions from animals are such a cause for concern.

For the study, the researchers collected sediment samples and analyzed trace gas, isotopes, and molecules from the Baltic worms and clams.

After careful analysis, the researchers found that 10 percent of the total emissions may be due to clams and worms.

The amount of methane the clams emit is comparable to 20,000 dairy cows, or put another way, as much as 10 percent of the entire Welsh dairy cow population.

“What is puzzling is that the Baltic Sea makes up only about 0.1% of Earth’s oceans, implying that globally, apparently harmless bivalve animals at the bottom of the world’s oceans may, in fact, be contributing ridiculous amounts of greenhouse gases to the atmosphere that is unaccounted for,” said Dr Ernest Chi Fru, from Cardiff University’s School of Earth and Ocean Sciences and co-author of the study.

The neglected source of greenhouse gas emissions could impact future policies regarding shellfish farming.

By Kay Vandette, Earth.com Staff Writer

Ant queens perform strange burial ritual

Ant queens who have chosen to co-found a colony were discovered performing a strange burial ritual if one of the co-queens died. When this happened, the surviving queen would sometimes bite and bury the dead queen, possibly to avoid the spread of infection.

The study was conducted by researchers from the Institute of Science and Technology in Austria and was published in the journal BMC Evolutionary Biology.

The team observed ant queens, who had co-founded a colony with a sick queen who later died, performed “undertaking behaviors,” such as biting the corpse to make it easier to transport, and then burying it.  

These undertaking behaviors were linked to a greater likelihood that the queen would survive, instead of getting infected themselves.

Christopher Pull, corresponding author of the study, explained why this behavior was out of the ordinary and surprising to the researchers.

Typically, queens avoid any risks to their health and survival so that they can be counted on for reproduction and the colony’s well-being. But queens do not seem to avoid sick queens, most likely due to competing for nesting sites, Pull noted.

Co-founding with a knowingly sick queen and burying that queen could expose the healthy queen to infection, but actually, the reverse was found to be true.

“We found that queens that perform these behaviors are actually less likely to contract infections from dead co-founders and are less likely to die compared to those that do not perform undertaking,” said Pull.

The researchers observed the queens of the black garden ant and discovered that if two queens shared a closed nest with only one chamber and one of them died, a large majority of the surviving queens would bite and bury the dead.

If the queens had an open nest with multiple chambers, most of the surviving queens would still bite the dead queen, but only 22 percent of the live queens would bury the corpse.

The researchers also wanted to explore how the introduction of pathogens would affect an ant queen’s choice to co-found a colony. The researchers exposed certain ant queens to fungal pathogens, making them sick.

Overall, the researchers found that healthy queens did not go out of their way to avoid co-founding with infected queens.

In another experiment, the researchers found that if one of the queens died, whether infected or not, the surviving queen still performed the same undertaking behaviors.

By Kay Vandette, Earth.com Staff Writer

Beaked whales break the mold and dive deeper for more prey

Beaked whales in the Bahamas surprised researchers when they were discovered diving deeper than expected for whales of their size. It had previously been thought that only larger whales could dive that deep in the water for longer periods.

Typically, larger whales dive tens to thousands of meters deep to forage for prey, while smaller beaked whales dive down only around 3,000 meters.

The dive capacity of larger whales, or Odontocetes as they are known, increases with body mass, as more oxygen can be stored to sustain the dive.

Now, with the discovery of the several beaked whales breaking the mold, researchers from the Scripps Institution of Oceanography suggested that certain beaked whales alternate between aerobic to anaerobic respiration to be able to dive deeper and for longer periods.

Aerobic respiration requires oxygen while anaerobic respiration produces energy without oxygen. By alternating between these two different types of energy production, the beaked whales can dive out of their usual comfort zones.

To test the theory, the researchers tagged 17 beaked whales, 13 melon-headed whales, 15 short-finned pilot whales, and 27 sperm whales.

The study also used satellite data to monitor the dive patterns of the different whale species as they foraged for prey in underwater canyons in the Bahamas.

The results showed two beaked whale species took long, deep, dives in contrast to their size but they also took longer to recover, with intervals between dives taking around 62 minutes.

The researchers had collected data on weight and concentrations of myoglobin (a muscle protein that binds oxygen), but those numbers only explained 36 percent of the variance in dive times.

The longer dive times are most likely linked to lactic acid that accumulates in the muscle during anaerobic respiration, which supports the researchers claim that alternating between the two  different types of respiration is why beaked whales can dive so deep.

The ability to dive deeper allows these beaked whales more options for prey, which in some cases can more plentiful deeper in the water.

By Kay Vandette, Earth.com Staff Writer

Image Credit: Bahamas Marine Mammal Research Organization

Octopus skin helped scientists develop new camouflage material

Octopus and cuttlefish are some of the most intelligent creatures in the world, a fact that scientists have known and studied for decades. But it’s not just their brains that can be called intelligent – it’s their skin as well. Both cephalopods are able to instantaneously change their skin pattern and color in order to camouflage and blend into their environment. But it doesn’t stop there; these animals can also mold their skin into a textured, 3D surface in order to mimic the landscape around them.

Now, a team of engineers at Cornell University have invented camouflage stretchable surfaces with programmable 3D texture inspired by the real skin of octopus and cuttlefish. The material mimics the 3D bumps on the surface of these animals’ skin – known as papillae. Cephalopods can express these papillae in one-fifth of a second in order to mimic textures, and then retract them in order to swim away without any hydrodynamic drag.

“Lots of animals have papillae, but they can’t extend and retract them instantaneously as octopus and cuttlefish do,” says Roger Hanlon, a cephalopod biologist at the Marine Biological Laboratory (MBL) who is the leading expert on cephalopod dynamic camouflage. “These are soft-bodied molluscs without a shell; their primary defense is their morphing skin.”

Papillae are what are known as a muscular hydrostat, which is a biological structure that is entirely made of muscle with no skeletal support – such as your tongue. Hanlon and members of his laboratory were actually the first to describe the structure, function, and biomechanics of the morphing 3D papillae in detail. However, their major breakthrough was in creating synthetic tissue groupings that contain programmable, 2D stretchable materials that can extend and retract into 3D shapes.

“This is a classic example of bio-inspired engineering,” says Hanlon. He also believes it has a range of potential applications, such as being able to reflect light in its 2D spaces and absorb light in its 3D shapes. “That would have applications in any situation where you want to manipulate the temperature of a material,” he says.

When animals have survived for millions of years in one of the least-friendly environments on earth, it makes sense that we should study their most dynamic traits in an attempt to mold them to our own uses. Some day soon, we may see wearable materials that can camouflage you just as well as a cephalopod!

By Connor Ertz, Earth.com Staff Writer

Herbivores could protect ecosystems from climate change

A new study from the University of British Columbia may offer up some hope for a strategy in preventing climate change. The answer? Herbivores. That’s right; researchers believe that plant-eating species may be a key factor in helping certain ecosystems survive global warming.

In their study, the researchers created mini-marine ecosystems on the shore of Ruckle Park on British Columbia’s Salt Spring Island. These ecosystems were built on hard plastic plates, allowing the temperature to be controlled. Limpets, an established herbivore species, were allowed on some plates, while they were made absent on others.

They were studying life in the intertidal zone, which is the area of the shore between low and high tide. Generally, it contains ecosystems consisting of starfish, mussels, anemones, seaweed, and barnacles. The interesting aspect of these intertidal ecosystems is that they experience huge temperature fluctuations as the tides go in and out – sometimes as much as 20 to 25 degrees Celsius. This means that the species in the intertidal zone must cope with significant temperature variation every day.

“These creatures are already living at their physiological limits, so a two-degree change – a conservative prediction of the warming expected over the next 80 years or so – can make a big difference,” said Kordas. “When heat waves come through B.C. and the Pacific Northwest, we see mass mortality of numerous intertidal species.”

Surprisingly, the researchers found that certain communities in the intertidal zone could survive even in the warmest summer temperatures – but only if limpets were present in their ecosystem.

According to Christopher Harley, senior author of the study and a professor of zoology at UBC, consumers such as sea otters and starfish like limpets, and these species are very important in maintaining biodiversity in aquatic ecosystems. Losing these species may destabilize ecosystems, so if we’re able to better protect species such as limpets, it may help make ecosystems more resilient.

“We should be thinking of ways to reduce our negative effects on the natural environment and these results show that if we do basic conservation and management, it can make a big difference in terms of how ecosystems will weather climate change,” says Harley.

Who would’ve thought that something so small could be so important to keeping complicated ecosystems intact?

By Connor Ertz, Earth.com Staff Writer

Birds need friends too! Those who do have longer lives

New research has found that birds who live next to their friends and family live longer and experience less stress.

A study conducted by researchers at the University of East Anglia monitored Seychelles warblers who live in the Seychelles Islands. The team examined how the birds interacted with each other and the impact those interactions had on their stress levels.

The results showed that birds who lived near family and friends did not fight with each other, and that birds who had friends and family close showed fewer signs of aging and stress.

The researchers were able to measure the warblers stress levels by looking at telomeres, which are the caps at the end of a chromosome.

Telomeres are important in gauging stress and aging because they erode faster as a result of both. The birds who weren’t fighting with their neighbors had longer telomeres.

“Territory owners who are constantly fighting with neighbours are stressed and have little time to do other important things – such as finding food and producing offspring – and their health suffers as a result,” said Kat Bebbington, lead author of the study.

Birds and other animals are like humans in that they “own” a piece of property, a home or nest that they defend against predators. Territorial disputes with unfamiliar neighbors result in a stressful environment and impacts health and longevity of the birds.

The research helps to show how birds socialize and interact with each other, particularly amidst habitat degradation where they find themselves in unfamiliar situations with close, unknown neighbors.

Bebbington and fellow researchers hope that this study will showcase the importance of understanding the complexities of bird relations and how they impact a bird’s health and well-being.

By Kay Vandette, Earth.com Staff Writer

Pests are becoming resistant to genetically modified crops

Genetically modified crops have been prevalent around the world for decades, helping increase crop yields and decrease destruction from pests. In 2016, over 240 million acres of genetically modified corn, cotton, and soybeans were planted around the world that contain insect-killing proteins from the bacterium Bacillus thuringiensis (Bt). These proteins kill caterpillar and beetle pests that would otherwise destroy the crops, but the proteins are harmless to people and considered to be environmentally friendly.

One of the main fears about Bt use, as well as the use of BT protein sprays used by some organic farmers, is that widespread use could result in significant evolution of resistance in pests. A recent study from the University of Arizona has analyzed this issue, finding the factors behind why certain pests adapt quickly to Bt proteins, while others don’t.

The study involved analysis of global data on Bt crop use and pest responses, including data from 36 cases representing responses of 15 pest species on every continent (minus Antarctica, of course). The results were published in the journal Nature Biotechnology.

“When Bt crops were first introduced in 1996, no one knew how quickly the pests would adapt,” says Bruce Tabashnik, head of the University of Arizona’s Department of Entomology. “Now we have a cumulative total of over 2 billion acres of these crops planted during the past two decades and extensive monitoring data, so we can build a scientific understanding of how fast the pests evolve resistance and why.”

Of the 36 cases studied, the researchers found 16 cases as of 2016 in which resistance substantially reduced the efficacy of Bt crops. In these cases, pests evolved resistance in an average time of just over five years. “A silver lining is that in 17 other cases, pests have not evolved resistance to Bt crops,” Tabashnik adds. Many of these crops continue to be effective even after 20 years.

In looking beyond just resistance statistics, the researchers wanted to determine what factors help keep resistance at bay. They found that two such factors were recessive inheritance of resistance in pests, and farmers planting a large amount of refuges. Refuges – for those of you who are not farmers – are areas of standard, non-Bt crops planted near Bt crops in order to reduce the chances that two resistant insects will mate with each other.

However, the most concerning finding of the study was that pest resistance to Bt crops is evolving faster now than ever. This is mainly because resistance to some Bt proteins results in cross-resistance to related Bt proteins produced by crops that are planted later.

Luckily, the development of a new type of Bt protein called a vegetative insecticidal protein (Vip) may be the answer we need. All other Bt proteins are part of another group of proteins, known as crystalline (Cry) proteins. Since these two groups of Bt proteins are so different, cross-resistance between them is very unlikely.

This study is the most comprehensive evaluation of pest resistance to Bt crops ever. Further research will help to increase our understanding of how these proteins affect pests and keep our crops safe.

By Connor Ertz, Earth.com Staff Writer

Image Credit: Alex Yelich/University of Arizona