Chimpanzees: 'New Girl' Forms Stronger Female Bonds

(Photo : Kara Schroepfer-Walker, Duke University)

When it comes to chimpanzees, it seems that the "new girl" may have the upper hand in former stronger female bonds, new research says.

Unlike most primates, female chimps are loners compared to males, spending about half their time either alone or with dependent kids.

"Chimpanzee females' more solitary existence isn't that surprising given their dispersal patterns," researcher Anne Pusey, a professor of evolutionary anthropology at Duke Unviersity, said in a statement. Meaning, while males stay with the group they were born into their entire lives, many females choose to leave their families and join new groups.

But despite their reputation for being aloof, recent studies suggest that some pairs of female chimps hang out together more than others. Now, as the new girl in the group, you would think that it would be hard to make friends. However, the Duke team finds that low-ranking "new girl" chimps actively seek out other gal pals with similar status, thereby forming strong social bonds.

In order to figure this out, and rule out the possibility that these chimps were merely crossing paths by chance, Pusey and colleagues analyzed 38 years' worth of daily records for 53 adult females in Gombe National Park, a 13.5-square-mile park in western Tanzania.

Over the years, the females were spotted in more than 600 female-female pairs. For each pair, the researchers measured how much their ranges overlapped, how much time they spent together, and how often they groomed each other - a symbol of friendship and bonding.

Based on their findings, it turns out that some female-female relationships are tighter than others.

Not surprisingly, mothers, daughters and sisters formed the strongest bonds. However, among unrelated females - which made up more than 95 percent of the twosomes they studied - low-ranking females were more likely to seek each other out than females from other social ranks.

"It doesn't necessarily mean that they like each other," Foerster was quick to add. "The lowest-ranking females are the newest to arrive. When a female migrates into a new group, she starts at the bottom of the social ladder. It may be that they're not really that into each other, but that they need to tolerate being in the same space."

Also, it could be that low-ranking females team up for support against harassment from higher-ranking females, or as a means to compete for food or spot predators.

Further study is needed to determine whether the "new girls" are true buddies, friends of convenience or merely acquaintances.

The results were published in the journal Animal Behaviour.

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Dogs and Humans: Special Bond Goes Back Earlier Than Thought

(Photo : Pixabay)

Dogs have long been known as man's best friend, and now new research shows that their special bond with humans may go back earlier than thought.

Previous genome-based estimates have suggested that the ancestors of modern-day dogs diverged from wolves no more than 16,000 years ago, after the last Ice Age. But now, new DNA evidence from an ancient Taimyr wolf bone - which has been radiocarbon dated to 35,000 years ago - finds that this species is the most recent common ancestor of modern wolves and dogs.

"Dogs may have been domesticated much earlier than is generally believed," Love Dalén of the Swedish Museum of Natural History said in a press release.

"The power of DNA can provide direct evidence that a Siberian Husky you see walking down the street shares ancestry with a wolf that roamed Northern Siberia 35,000 years ago," added Pontus Skoglund, the study's first author. To put that in perspective, "this wolf lived just a few thousand years after Neanderthals disappeared from Europe and modern humans started populating Europe and Asia."

It's likely that many other dog breeds today are also related to prehistoric regional wolf populations, helping to explain why there is such incredible diversity among dogs.

Skoglund and his colleagues made the discoveries after analyzing a small bone picked up during an expedition to the Taimyr Peninsula in Siberia. Wolves are common on the Taimyr Peninsula, and the bone could have easily belonged to a modern-day wolf. However, DNA tests revealed that the bone belonged to the prehistoric Taimyr wolf.

Though this study allows us to better understand dogs' special relationship to humans, the precise moment when dogs were "domesticated" still eludes scientists because the meaning of the word is up for debate.

Regardless, there is no denying the loving bond that man - and woman - shares with their dogs.

The findings are described in further detail in the journal Current Biology.

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Wind Turbines: Hearing of UK Harbor Seals May be At Risk

(Photo : © belizar / Fotolia)

Scientists are still working to figure out how various noise pollution affects marine animals, and now new research suggests that the building of wind turbines may be putting the hearing of UK harbor seals at risk.

There are currently 1,184 offshore wind turbines located along the coast of the United Kingdom, collectively generating around 4GW of power. And last year, construction began on hundreds more turbines, the impact of which on sea mammals is still widely unknown.

To figure out if nearby seals' hearing may be hurt as a consequence, a team of ecologists from the University of St Andrews attached GPS data loggers to 24 harbor seals while offshore wind turbines were being installed back in 2012. They collected data on the seals' locations and their diving behavior, comparing it with noise from pile driving during wind turbine construction.

Offshore wind turbines are installed using pile drivers - essentially large hammers that drive the foundation posts into the seabed - which produce short pulsed sounds every few seconds.

"These are some of the most powerful man-made sounds produced underwater, noise capable of travelling large distances underwater," lead study author Dr. Gordon Hastie said in a statement.

According to the study results, half of the tagged seals were exposed to noise levels that exceeded hearing damage thresholds.

"Like most marine mammals, harbor seals have very sensitive underwater hearing at a much broader range of frequencies than humans," Hastie said. "Seals probably use underwater hearing during the mating season and to detect and avoid predators. They may also rely on their hearing for navigation and finding prey."

These findings could have potential important implications, as seals are protected under European law, and the construction of wind turbines may have to be reevaluated if it is determined that they affect the animals' conservation status.

"Our predictions highlight that seals may routinely be exposed to potentially hazardous levels of underwater noise during pile driving, with potential implications for the conservation status of some populations. To reduce these potential impacts, regulators and industry are currently investigating engineering solutions to reduce sound levels at source, and methods to deter animals from damage risk zones in order to potentially reduce auditory damage risk," Hastie added.

Next, the research team plans to use special "seal headphones" to further evaluate UK seals' hearing, as well as monitor individual seals' movements at sea, and collect long-term data on their growth, reproduction and survival.

Harbor seals live around the coasts of the North Atlantic and North Pacific from the subtropics to the Arctic. Around 30 percent of European harbor seals are found in the United Kingdom alone.

A viral epidemic swept through seal populations in the region back in 1988 and again in 2002, decimating their numbers, and the sea mammals are still on their road to recovery. And though wind turbines provide a unique alternative energy source for humans, if they are proven to negatively impact this recovering species, scientists may have to look into engineering solutions to reduce noise levels.

The findings were published in the Journal of Applied Ecology.

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Lions and Leopards: Hunting Ban to be Lifted in Zambia

(Photo : Pixabay)

Despite concerns from conservationists, Zambia is preparing to lift a 2013 ban on the hunting of wild lions and leopards in order to raise funds.

This move may seem "extremely outrageous," however, tourism and arts minister Jean Kapata assures critics that the profits gained from hunting these big cats could benefit wildlife conservation as well as the livelihoods of local people.

"I am lifting the ban on the following conditions: the guidelines are drafted into a statutory instrument so that they become part of the wildlife law," she said, according to the Zambia Daily Mail. "Lion hunting should only resume in the 2016-17 hunting season and not this year. Leopard hunting can resume this year - 2015-16 season - but with very cautionary quotas."

Laws against these very types of hunts were instilled in January 2013, when it was clear that over-harvesting, hunting of underage lions and habitat loss were causing lion populations to decline. However, now those rules are being rescinded when Zambia locals and their wildlife resources became seriously affected as a result.

So based on this new knowledge, government officials plan to adopt prescribed guidelines, rather than invoke an outright ban on wildlife hunting.

"Some of the regulatory methods are currently being used in Tanzania, Mozambique and Zimbabwe. These have been found to be effective," Kapata noted.

However, with poaching an ongoing threat in Africa, conservationists like those from the Green Party of Zambia condemn the decision.

"We all know that the number of lions and other big cat species in Zambia's major parks is depleted and limited due to poaching and other anthropogenic activities," the group's president, Peter Sinkamba, told the Lusaka Times.

As of 2013, Zambia's lion population is estimated to be between 2,500 and 4,700 individuals.

Leopards, on the other hand, are listed as a near-threatened species on the IUCN Red List, and have long been hunted for their beautiful, soft fur - used to make coats and ceremonial robes - as well as for their claws, whiskers, and tails, which are popular as fetishes.

"Much as we are aware that the PF [Patriotic Front] government is facing serious budget deficit challenges," he added, "it is extremely outrageous to resort to unleashing safari hunters on to limited populations of big cat species, regardless of the fact that safari hunting is allegedly most profitable."

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Right Whales May Boast Unique Voices

(Photo : Jenny Tennessen/Syracuse University)

Scientists are just beginning to understand how whales produce sound, and now new research suggests that like humans, North Atlantic right whales boast unique individual voices.

It is common for us to recognize different people based solely on the way they sound - for example, the resonating bass of James Earl Jones is easily distinguished from the nasal laugh of actress Fran Drescher. This idea has recently been applied to other members of the animal kingdom, including dogs and deer. And now, a team from Syracuse University is working to apply the theory of individually distinctive vocal characteristics to North Atlantic right whales.

As an endangered species, this research could potentially be used to identify and track individuals and improve conservation efforts for right whales.

During the study, scientists were able to correctly distinguish 13 different individual whales based on a combination of vocal characteristics, including length of the calls and the fundamental and harmonic frequencies.

Right whales make about a half-dozen different types of calls, but the Syracuse team focused on the characteristics of the "upcall" - a vocalization that lasts about 1-2 seconds and rises in frequency from around 100 Hz to 400 Hz, at the low end of frequencies audible to human ears. The upcall is the most commonly produced call among all ages and sexes of right whales, and is likely used to announce their presence and "touch base" with other whales.

Based on the characteristics that distinguish human voices, the researchers thought the emphasized harmonic frequencies of the upcalls, called formants, would best distinguish individual whales.

"What I found was that there actually wasn't much difference in the formants, but one of the variables that came out as most important in discriminating the individuals was the duration of the call," researcher Jessica McCordic said in a statement.

In the end, the team found that analyzing a combination of variables, including the formant, the duration of the calls, and the rate of the fundamental frequency change, could distinguish between the upcalls of the 13 individual whales identified in the archival data set.

For centuries, humans have hunted North Atlantic right whales - which feed on tiny zooplankton in shallow waters off the east coast of the United States and Canada. Now, this marine species is listed as critically endangered, with population numbers estimated at around 450 whales.

But by better understanding their unique voices, scientists may be able to improve tracking of these whales, which spend most of their time under water. This could bolster conservation efforts and help the species on its road to recovery.

The team will present their results at the 169th meeting of the Acoustical Society of America, held May 18-22, 2015 in Pittsburgh.

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Fruit Flies: Do They Feel Emotion?

(Photo : Pixabay)

With summer right around the corner, it'll soon be time for a good old-fashioned picnic. The only thing that might ruin your good time is a pesky fruit fly, which can be shooed away with the simple wave of your hand. But have you ever thought about what that fruit fly could be thinking, for example, if it's actually afraid as it flees the scene? Well, researchers now suggest that fruit flies may be able to feel emotion.

At least, that's according to a new study published in the journal Current Biology, which details how a fly's response to a shadowy overhead stimulus might be analogous to a negative emotional state such as fear - a realization that could one day help us better understand the neural circuitry involved in human emotion.

Although you might think that mice would be more suitable for studying human emotion, since they are closer to humans on the evolutionary family tree, insects actually provide valuable information also. In this case, the fruit fly has a much simpler neurological system that is easier to study. Nonetheless, studying emotions in insects or any other animal can also be tricky.

When it comes to studying emotion in animals, anthropomorphosis is common.

"There are two difficulties with taking your own experiences and then saying that maybe these are happening in a fly. First, a fly's brain is very different from yours, and second, a fly's evolutionary history is so different from yours that even if you could prove beyond any doubt that flies have emotions, those emotions probably wouldn't be the same ones that you have," postdoctoral scholar William T. Gibson, first author of the paper, said in a statement. "For these reasons, in our study, we wanted to take an objective approach."

To achieve this goal, Gibson and his colleagues broke down the idea of emotion into basic building blocks - like the way the color orange can be broken down into two colors: red and yellow. This way, they operated under the assumption that "emotions are a type of internal brain state with certain general properties that can exist independently of subjective, conscious feelings, which can only be studied in humans," explained co-author David Anderson.

"That means," he said, "we can study such brain states in animal models like flies or mice without worrying about whether they have 'feelings' or not. We use the behaviors that express those states as a readout."

"And if we can show that fruit flies display all of these separate but necessary primitives, we then may be able to make the argument that they also have an emotion, like fear," Gibson added.  (Scroll to read on...)

(Photo : Pixabay)

The researchers observed the insects in the presence of a fear-inducing stimulus - an apparatus that would pass a dark paddle over the flies' habitat. Using a software program to track the flies' movements, the team found that the insects displayed all five primitives attributed to the emotion of fear.

For example, when the paddle passed overhead, the flies would either freeze, or jump away from the stimulus, or enter a state of elevated arousal. What's more, repeated exposure to the stimulus produced an increase in each response, suggesting that their fear heightened each time.

"For us, that's a big step beyond just casually intuiting that a fly fleeing a visual threat must be 'afraid,' based on our anthropomorphic assumptions. It suggests that the flies' response to the threat is richer and more complicated than a robotic-like avoidance reflex," Anderson explained.

"Our work can get at questions about mechanism and questions about the functional properties of emotion states, but we cannot get at the question of whether or not flies have feelings," Gibson was quick to point out.

Nonetheless, the researchers hope to use their new technique to gauge whether emotion primitives exist in higher organisms, such as mice or even humans.

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Ants Double Survival Rate with Impressive Jaw Jumps

(Photo : Adrian Smith)

Ants are pretty clever insects, with researchers recently finding that certain species can even double their survival rate using impressive jaw jumps.

According to a new study published in the journal PLOS ONE, some species of trap-jaw ants use their spring-loaded mandibles to hurl themselves out of harm's way when an ant-trapping predator is stalking nearby. When all other escape methods fail, this trick significantly increases their chances of living to see another day.

The mandibles of the trap-jaw ant, Odontomachus brunneus, can slam shut at speeds over 40 meters per second (144 kilometers per hour, or 89 mph), instantaneously marring a prey insect or enemy ant. They also are used for more routine tasks, such as digging nests or tending to eggs and larvae.

Previous studies have reported that trap-jaw ants sometimes jump with their jaws, "but it was unknown whether this behavior was meant to help them get away from a predator, and it wasn't clear that it actually improved their odds of surviving an encounter with a predator," graduate student Fredrick Larabee from the University of Illinois, who led the study, said in a statement.

But this time around, researchers were finally able to verify that the high-powered mandibles do in fact aid the ants' survival by allowing them to eject themselves from a dangerous dilemma.

Pit-building antilions (predator ants) are one such species that may try to devour trap-ants. The first part of their strategy is to dig cone-shaped pits in the sand and bury themselves at the bottom, anxiously waiting for a victim to fall in.

"If an ant falls into the pit, it tries to run away, but the sand crumbles beneath its feet," Larabee explained. "This pulls it closer to the center of the pit where the antlion is waiting."

(Photo : Flickr: Bernard DUPONT)

Here, the antilion sometimes employs its second strategy, which involves hurling the sand to cause a tiny avalanche, further destabilizing its target. If its prey tumbles to the bottom of the pit, it's doomed, as the antilion can grab it with its strong mandibles.

But, to see how trap-jaw ants fared in this situation, they dropped several of them into antlion pits in the lab to see if, and how often, the ants used the jaw-jumping maneuver to escape from an actual predator. The ants usually tried to run out of the pit, and sometimes were successful. If that strategy failed, they sometimes jumped with their jaws.

"The ants were able to jump out of the pits about 15 percent of the time in their encounters with antlions," Larabee said. "But when we glued their mandibles shut before dropping them in the pits, they couldn't jump at all. It cut their survival rate in half."

Previous research has showed that O. brunneus sometimes adopts an unusual body posture just before jumping, according to the study. It lowers its head, making contact with the ground, and occasionally raises a leg before deploying its mandibles to hurl itself into the air.

"Based on our earlier studies, if the ant was striking a prey object, the distance between the ant and the prey was about the length of the trigger hairs that come off the mandibles," said entomology professor Andrew Suarez, who helped conduct the study. "But when they were jumping off a surface, you would often see the ants put their entire face against the surface, and it was more of a pushing behavior than a striking behavior."

The study shows researchers how a trait or capability that evolved for one purpose can be adapted for different uses.

"In this case, a tool that is very good for capturing fast or dangerous prey also is good for another function, which is escape," Larabee added.

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Male Hormones Make Female Lemurs Queen

(Photo : Flickr: nomis-simon)

The traditional way of the animal kingdom is that males rule, and females reap the benefits of being pampered baby-makers. Of course there are always exceptions, especially among birds, arachnids, and even humans. However, there is one exception that came as a bit of a surprise. Female lemurs it seems will often bully their mates, stealing food, marking territory, and even ruling over their neighbors. Now researchers think they have determined what makes these imposing lady lemurs so different.

"If a male lemur is enjoying a patch of sunlight, for example, a female is likely to push him aside and take his spot," Joseph Petty, who studies the animals and their social patterns with the Duke University Lemur Center, explained in a recent statement.

Traditionally, when this kind of dominant or 'bullying' behavior occurs, the largest and strongest of a group are the instigators. This usually characterizes alpha males, but not all the time. Among spotted hyenas, for instance, females can steal prizes and even expect the privilege of eating first because they are heavier than males.

However, that's exactly why female dominance among lemurs is puzzling. They are not larger, stronger, or more deadly than their male counterparts, so what could it be that gives them a knack for dominance?

Hormones, Petty and his colleague argue, is probably the root of this unusual behavior. Like most mammals, female lemurs have significantly less testosterone than males regardless of their location or species. However, when the researchers compared six lemur species, they found that the females of some have higher testosterone levels than others.

Petty and evolutionary anthropologist Christine Drea then tested 30 lemurs from six closely-related lemur species in all. In four of the species, females are at the top of the pecking order, and in the other two species the sexes have equal status.

Predictably, they found that the dominant females from the lady-run species had significantly higher male hormone levels than the females from the two remaining groups.

"It's strong evidence that hormones are playing a role," Petty said, adding that evolution likely had a hand in making this common among some whole species.

In other creatures, like birds, elevated testosterone often means the young need to be aggressive to survive. A similar pattern may have occurred with some of lemurs, with it eventually leading to an intriguing change in who dominates who.

Results and methods of the study were published in Scientific Reports.

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Massive Bird Invasions Linked to Climate Shifts

(Photo : Pixabay)

Massive bird invasions taking place across the United States and Canada, a phenomenon that has long puzzled scientists and birdwatchers alike, is reportedly linked to climate shifts, new research indicates.

Over the years, vast numbers of birds from Canada's boreal forests have migrated hundreds-of-thousands of miles south from their usual winter range. While previous studies have blamed these so-called irruptions on food shortages, it seems that climate also plays a role. Specifically, persistent shifts in rainfall and temperature drive boom-and-bust cycles in forest seed production, which in turn drive the mass migrations of pine siskins.

"It's a chain reaction from climate to seeds to birds," atmospheric scientist and lead author Court Strong, from the University of Utah, said in a news release.

"We've known for a long time that weather was probably important, but prior analyses by ecologists have been unable to identify exactly what role weather was playing in this phenomenon," says ecologist Walt Koenig, a senior scientist at the Cornell Lab of Ornithology and co-author of the new study incorporating climate science. "It's a good example of the value of interdisciplinary work," added study co-author Walt Koenig.

Many seed-eating boreal species are subject to irruptions, including Bohemian and cedar waxwings, boreal chickadees, red and white-winged crossbills, purple finches, pine and evening grosbeaks, red-breasted nuthatches, and common and hoary redpolls. But during this study researchers chose to focus on the pine siskin - the most widespread and visible of these bird migrants. (Scroll to read on...)

(Photo : Steve Byland / Fotolia)

Pine siskins breed during summer in Canadian boreal forests, where they rely heavily on tree seeds for food. When seeds are abundant, pine siskins in eastern North America largely stay put through the winter. But when seed production is poor, pine siskins and other boreal birds move elsewhere to find overwintering habitat with adequate food. During these irruptive years, the eastern populations of pine siskins forage as far south as the Appalachian Mountains, unlike western populations.

In fact, amateur birdwatchers have seen dramatic shifts in migration patterns over the years, For example, winter 1990 saw a massive "superflight" south of the boreal forest, while during the winter ending in 2004 there was a near absence of boreal pine siskins in the United States.

To get to the bottom of this phenomenon, researchers combined FeederWatch observations - a project that involved more than two million bird sightings - with climate data in a statistical analysis. This allowed them to link bird population movements with established patterns of climate variability across North America. As expected, they found that extremely cold winters tend to drive birds south during the irruption year.

More surprisingly, it seems that there is a teeter-tottering pattern between the north and south that influences bird migrations two to three years later. When it is wet and cold in one region, hindering seed production, the weather is warmer and more favorable in the other region.

By pinpointing this unique climate pattern that sets the stage for irruptions, the scientists can, in theory, predict the events more than a year in advance.

What's more, this study also raises important questions about how global climate change is affecting bird populations across the country, by leaving birds like the pine siskin with poor seed supplies.

"The boreal forest is the world's largest terrestrial biome and is home to more than half of North America's bird species," co-author Benjamin Zuckerberg concluded. "It is likely that these irruptions, driven by climate, are a critical indicator of how climate change will affect northern forests and their dependent species."

The findings were published in the journal PNAS.

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You Won't Believe What Neil Diamond (the chicken) Decided to Swallow [VIDEO]

(Photo : Nat Geo Wild / Beck Media)

It's one thing believe in the term "you are what you eat," but when 'Neil Diamond; the cockerel decided to swallow a whole diamond earring, he may have been taking things too far. Thankfully, Hawaii's most tireless traveling vet, Dr. Scott Sims, was on the case.

In the latest episode of Aloha Vet, (airs this Sat.) Sims explains to Neil's owner, Bridgett, that he probably went after the shiny piece of jewelry while giving into his own biological instincts. That's because, believe it or not, chickens naturally swallow course pebbles to help with their digestion. Because the birds gobble their food whole, they require these stones - which get stored in the gizzard - to help grind things down. And when an old gizzard stone grows too smooth, it's owner will hack it out and go looking for another one.

According to Sims, that's probably what happened in the case of Mr. Diamond. Unfortunately, Neil happened to share an eye for fine jewelry with Bridgett's boyfriend.

"This pair of earrings was actually given to me by my boyfriend when he had come from Afghanistan, so they do hold sentimental value," she explained.

The earring was not only diamond, but had a white gold setting - a revelation that relieved Sims, as it meant there is little threat of heavy metal poisoning for Neil. However, it certainly must have cost a pretty penny - a value currently residing inside the gizzard of a cranky cockerel.

So what's to be done? You can check out the clip below to find out.

[Credit: Nat Geo Wild]

Some clients live in hard-to-reach locations, but if an animal needs help, Sims always finds a way to get there, even if he has to walk, ride a horse, drive an ATV, fly a plane or swim. It's a wild job that's an adventure every day. "Aloha Vet" airs Saturdays at 9 PM ET/PT on Nat Geo WILD.

For more great nature science stories and general news, please visit our sister site, Headlines and Global News (HNGN).

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How Did Bird Nests Evolve?

(Photo : Miramiska / Fotolia)

Bird nests, though it may not seem like it, are incredibly diverse, differing in nest location, structure, materials, and more. For instance, they could be on the ground or hanging from a tree, made out of twigs and grass, or even saliva. Yet despite their variety, we know very little about the forces that shaped their evolution. Now, new research is shedding light on the subject.

Specifically, researchers from the University of St. Andrews in Scotland are testing the hypothesis that domed-shaped nests arose as a result of some species transitioning to nesting on the ground, where the risk from predators is greater.

Surprisingly to scientists, previous research has rarely focused on why different bird species build such drastically different nest structures.

"I thought this was strange," researcher Zachary Hall said in a statement, "because the shape of a nest seems to be the most striking and diverse feature across bird species."

Although the idea that competition for nest sites, forcing some birds to the ground where predators were a threat, was first proposed nearly 20 years ago, techniques at the time did not provide a way to test the theory. But now, researchers are able to use more advanced statistical techniques to find the answer.

Hall and his colleagues collected previously published descriptions of the nests of 155 species of babbler and mapped nest height and structure to the birds' family tree.

Their analysis confirmed that babblers' ancestors likely built above-ground, cup-shaped nests, and that the addition of a dome to cover the nest corresponded with switching to nesting at ground level.

"This new study... looks at the evolution of two key aspects of animals as architects: how they shape their homes and where they put them," said Don Dearborn, an expert in the evolution of reproductive strategies in birds. "It shows very nicely how we can take advantage of recent progress in avian phylogenetics to test ideas about the evolutionary history behind the modern-day co-occurrence of particular pairs of traits."

The results were published in the journal The Auk: Ornithological Advances.

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Dolphin Hunts in Solomon Islands May Threaten their Survival

(Photo : Pixabay)

Dolphin hunts in the Solomon Islands, a cultural tradition, may threaten the survival of this species, according to new research. It also is casting a spotlight on the increasing vulnerability of small cetaceans around the world.

While whale hunts - particularly those that occur in Japan - gain more attention, this new study shows that "drive-hunting" dolphins should also be a major concern. These friendly marine animals are valued for their teeth, of all things, which are used to make jewelry.

In fact, from 1976 to 2013, more than 15,000 dolphins were killed by villagers in Fanalei alone, where a single dolphin tooth can fetch the equivalent of 70 cents ($0.70 USD) - an increase in value of five times just in the last decade.

"In the Solomon Islands, the hunting is as much about culture as economic value," study co-author Scott Baker, associate director of the Marine Mammal Institute at Oregon State University, said in a news release. "In other parts of the world, however, the targeting of dolphins and other small cetaceans appears to be increasing as coastal fishing stocks decline.

"The hunting of large whales is managed by the International Whaling Commission," he added. "But there is no international or inter-governmental organization to set quotas or provide management advice for hunting small cetaceans. Unregulated and often undocumented exploitation pose a real threat to the survival of local populations in some regions of the world."

But controlling the number of dolphins killed in the Solomon Islands may prove to be difficult. That's because the drive-hunting of dolphins has a long history in the Solomon Islands, particularly at the island of Malaita, according to researchers.

Remarkably, in 2010, the most active village, Fanalei, suspended hunting - in exchange for financial compensation from an international non-governmental organization. However, the villagers quickly resumed hunting in 2013.

"After the agreement broke down in 2013, a local newspaper reported that villagers had killed hundreds of dolphins in just a few months," noted Marc Oremus, a biologist with the South Pacific Whale Research Consortium and lead author on the study. "So we went to take a look."

Oremus and his colleagues visited Fanalei in March 2013 to document the impact on the local dolphin population, and examine detailed records of the kills. During the first three months of that year, villagers killed more than 1,500 spotted dolphins, 159 spinner dolphins, and 15 bottlenose dolphins - one of the largest documented hunts of dolphins in the world. (Scroll to read on...)

(Photo : Oregon State University)

It even rivals the more-industrialized hunting of dolphins in Japan, Baker said - such as those that occur in Taiji's Hatajiri Bay, commonly known as "the cove," where dolphins are commonly corralled in large groups.

"It is also troubling that teeth are increasing in cash value, apparently creating a commercial incentive for hunting dolphins," the researcher added.

In drive-hunting, the hunters operate in close coordination from 20 to 30 traditional canoes. When dolphins are found, the hunters used rounded stones to create a clapping sound underwater. The hunters maneuver the canoes into a U-shape around the dolphins, using sound as an acoustic barrier to drive them toward shore where they are killed.

"The main objective of the hunt is to obtain dolphin teeth that are used in wedding ceremonies," Oremus said. "The teeth and meat are also sold for cash."

What's more is that the Solomon Island hunters understand the risk of exploiting the population, though they continue their drive-hunts.

"The government of the Solomon Islands has contributed substantially to research in recent years, but is not well-equipped to undertake the scale of research needed to estimate abundance and trends of the local dolphin population," Oremus said. "This problem exists in many island nations with large 'Exclusive Economic Zones.'"

Hopefully this and other research will be able to shed more light on how drive-hunting dolphins impacts these animals, as well as other small cetaceans, and will allow policymakers to come up with a sensible solution.

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The 'Lazy' Sunfish is Actually an Active Killer

(Photo : Flickr: Ilse Reijs and Jan-Noud Hutten)

If you've ever seen a massive sunfish in the ocean, it's hard not to think of these animals as lazy. That because the strangely shaped animals tend to just drift around in surface currents while they soak up the Sun - a behavior that earned them their common namesake. Now however, new research has found that while these 'lazy' fish aren't darting around, they are diving deep to ravage unsuspecting prey.

That's at least according to a study recently published in the Journal of Animal Ecology, which details how sunfish (Mola mola) are surprisingly aggressive and even wasteful predators when they leave their sunny waters for deep-ocean dives.

To determine this, a team of experts attached accelerometers to several wild sunfish found near Funakoshi Bay, off the east coast of Japan, and monitored when and where they swam. They found that while they spend about 40 percent of daylight hours within the top five meters of ocean basking in the Sun's rays, they spend the rest of their time diving to depths of about 200 meters. The tracking devices even revealed that these slow and massive fish, weighing up to about 1000 kilograms (~2200 lbs) can reach depths of a whopping 800 meters (~0.5 mi). (Scroll to read on...)

(Photo : Flickr: Ilse Reijs and Jan-Noud Hutten)

But what are they doing so deep?  The team attached several advanced monitors, including a video camera to more wild sunfish and discovered that theanimals were hunting jellyfish and other jelly-like invertebrates (mostly siphonophores). Interestingly, the Mola mola weren't even eating all of their prey, choosing instead to tear the jellies to bits before devouring their gonads and oral arms in particular - parts significantly more nutritious, compared to the iconic bell of your run-of-the-mill jellyfish.

So if sunfish are actually such violent and active predators, why do they laze around so much near the surface? The researchers also determined that the sunfish lost a great deal of body heat every time they dived to colder depths. Those hours of lazing in the Sun's rays, the researchers concluded, are then very necessary for the fish to warm up enough to avoid freezing during their next dive.

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Massive Whales Lack Caution, Explains for Ship Collisions, Say Experts

(Photo : NOAA / Florida Fish and Wildlife Conservation Commission)

It's no small secret that ship strikes are a big threat to whales across the globe. Now a new study suggests that the largest of whales - particularly blue whales - may be the most vulnerable of all, as they lack the sort of caution and evasiveness that they would of developed had they ever actually had to worry about predators.

Between 1988 and 2012, there were 100 documented large whale ship strikes along the California coast alone, according to the NOAA, and the agency suspects that the large majority of these incidents remain unreported.

"Evidence of ship strikes comes from a range of sources including direct observations from vessels and examination of whale carcasses found floating at sea," the International Whaling Commission (IWC) reports. "However, for every incident that is observed and reported there will be many others that are missed. This makes assessing the conservation implications of ship strikes very difficult."

Yet despite that admission, the IWC goes on to assert that for right whales in particular - a baleen species only second largest to blues - the ship strike mortality rate is worryingly high.

"It is thought that mortality due to ship strikes may make the difference between extinction and survival for this species," the commission reports. (Scroll to read on...)

(Photo : NOAA Fisheries / Alisa Schulman-Janiger)

That's why researcher Jeremy Golbogen recently led a study of massive baleen whales, looking to blue whales in particular to confirm something he has long suspected.

"It's not part of [large whales'] evolutionary history to have cargo ships killing them, so they haven't developed behavioral responses to this threat," Golbogen, an expert of biology at Stanford Univerwsity's Hopkins Marine Station, explained in a recent statement. "They simply have no compelling response to avoiding these dangerous ships."

And if you think about it, that actually makes a lot of sense. The largest aquatic mammals in the world, blue whales can grow up to 82 feet long and weight a whopping 420,000 pounds as adults. What kind of predator would be crazy enough to attack them?

Without experiencing a fear of being eaten, the blue whale spends its time gleefully siphoning tons and tons of plankton and other small creatures from the ocean with its iconic baleen plates. Recent research has revealed that its physiology even radically changed to help facilitate this sole purpose.

This occored while other species continued to live in an eat-or-be-eaten world, learning appropriate levels of caution from birth and adapting new ways to reflexively avoid a threat.

In a new study recently published in Endangered Species Research, Golbogen and his colleagues argue that this could be why the traditional warning signs supposedly designed to warn whales when a large ship is fast-approaching (flashng lights, sound pings, etc) just don't do the trick.

After tracking the movements of nine blue whales with suction cups for 24-hour periods, the researchers determined that the closest thing to an avoidance strategy these animals have is a "startle response" in which they essentially play dead. (Scroll to read on...)

(Photo : Craig Hayslip, courtesy of OSU Marine Mammal Institute) A blue whale near a research and tagging vessel.

"Blue whales have a subtle and not very convincing ability to get out of the way of oncoming ships," said Goldbogen. "Instead of diving, where the animal kicks tail up and goes down vertically, they just sink horizontally. This results in a slow dive and leaves them susceptible to ship strikes."

Whales often have to dive about 30 meters below the surface to avoid a close-encounter with an oncoming ship. Unfortunately, this study revealed that the blue whales sank at about a half a meter per second, and made no move to speed up that decent. This resulted in plenty of near-misses and while no collisions were observed during the study, the researchers also suspect that this behavior can also lead to many ship strikes.

Still, while that's more cause for worry, the researchers add that this revelation is an important step in developing new ways to keep whales and ships from fatally meeting. Next, they plan to expand their work to other large whales, like the iconic humpback whale, in a bid for more behavioral data.

For more great nature science stories and general news, please visit our sister site, Headlines and Global News (HNGN).

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Huge Whales Boast Unique 'Bungee Cord' Nerves

(Photo : Flickr: Amila Tennakoon)

Baleen whales are indisputably huge creatures and rorqual whales are the largest group of them all, reaching up to a stunning 180 metric tons of weight. Even the smallest of this group, the northern minke whale, can weight a whopping 9.9 short tons. Being so big, it's not a stretch to assume their biology might be a little different than our own, and now a new study has proven it so. Rorqual whales, it seems, have unique nerve tissue that is just as thick and stretchy as your run-of-the-mill bungee cord.

"This discovery was totally unexpected and unlike other nerve structures we've seen in vertebrates, which are of a more fixed length," Wayne Vogl, a researcher with the University of British Columbia's cellular and Physiological Sciences department explained in a statement.

"The rorquals' bulk feeding mechanism required major changes in anatomy of the tongue and mouth blubber to allow large deformation," he added, "and now we recognize that it also required major modifications in the nerves in these tissues so they could also withstand the deformation."

What Vogal is talking about is the intriguing way in which baleen whales feed. You could think of your traditional baleen whale much like a massive vacuum. Opening its gaping maw as wide as physically possible, a whale will let a stunning portion of its body fill up with the water, stretching its mouth and insides to the fullest extent of their impressive elasticity. Then the whale seethes that scooped water out through its iconic comb-like tooth plates, leaving only heaps of tiny prey, like krill, copepods, and even small fish to be swallowed. (Scroll to read on...)

(Photo : University of British Columbia)

To account for that impressive elasticity, the whales' mouths must boast structural changes not seen in true toothed whale varieties, and these 'bungee-like' nerves are just another adaptation to add to the list.

Comparatively, in humans, over-extending nerves usually damages them. For roquals, however, the nerve cells are packaged inside a central core in such a way that the individual nerve fibers are never truly stretched, they simply unfold.

The researchers now hope to further investigate how these nerve systems fold and unfold so efficiently.

"This discovery underscores how little we know about even the basic anatomy of the largest animals alive in the oceans today," added Nick Pyenson, of the Smithsonian's National Museum of Natural History. "Our findings add to the growing list of evolutionary solutions that whales evolved in response to new challenges faced in marine environments over millions of years."

The findings are detailed in the journal Current Biology.

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Unrecognized Species of African Elephants Face Extinction

(Photo : Pixabay)

It's no secret that elephants continue to be threatened by the illegal ivory trade - an industry fueled by wealthy investors and a growing number of poachers looking to strike it rich. However, some conservationists have long contended that protecting healthy populations could help mitigate losses caused by frequently poached groups. Now a new review is condemning this little-known strategy, claiming that it could doom an entire species of African elephant to extinction.

But wait... how exactly could ignoring one group of elephants help global populations as a whole? The sad reality is that despite international efforts and the support of superstars like basketball's Yao Ming, African elephants are still slowly sliding towards extinction. Shrinking habitats and poaching, of course, continue to prevent their dwindling populations from recovering.

There just isn't enough money for animal protection to go around, and the difficult to manage ranges of African elephants remain largely short-staffed. That's why conservation groups have to pick and choose where their money goes. More often than not, that means aiming for the safe choice for one species - a region that has already seen some success and high chance of recovery.

However, that also means many of the worst areas remain unattended, with conservationists simply hoping that gains made in attended parts of the world will help mitigate the inevitable losses. (Scroll to read on...)

(Photo : pixabay)

"Although elephant populations may at present be declining in parts of their range, major populations in Eastern and Southern Africa, accounting for over two thirds of all known [African] elephants on the continent, have been surveyed, and are currently increasing at an average annual rate of 4.0% per annum... If current rates of increase continue, the number of elephants born in these populations between 2005 and 2010 will be larger than the currently estimated total number of elephants in Central and West Africa combined. In other words, the magnitude of ongoing increases in Southern and Eastern Africa are likely to outweigh the magnitude of any likely declines in the other two regions," the IUCN Red List reports concerning the "vulnerable" Loxodonta africana.

However, not everyone thinks this is good news. Alfred Roca, a member of the Carl R. Woese Institute for Genomic Biology, argues that many conservation groups are overlooking a very important fact: the African elephants in a recovering southeastern Africa are very different that the pachyderms found in Central Africa.

"They are not recognizing the forest elephant as a separate species despite all the research that has definitively established this," Roca said in a recent statement. (Scroll to read on...)

(Photo : pixabay) savannah elephants

Roca points to 15 years of genetic and morphological (physical) studies that have confirmed that there are two species of African elephants, dozens of which are cited in a new literature review.

"The two African elephants diverged about six million years ago," he explained, adding that current African elephant conservation strategies are "like saying, 'We increased the lion population, which will more than make up for the fact that tigers are going extinct.'"

"By not recognizing two species, these organizations may be condemning the African forest elephant to extinction," Roca concluded.

"The species are not shown as separate entities on the official United States List of Endangered and Threatened Wildlife or on the appendices to the Convention on International Trade in Endangered Species (CITES)," added Ronald Nowak, author of Walker's Mammals of the World.

He expressed his agreement with Roca and the researcher's colleagues that the specis should be treated as separate conservation targets, explaining that the next edition of his natural world guide will include a clear distinction between African forest (Central) and savannah (south, east) elephants.

In fact, the species are so distinct that forensic analysis of poached ivory can even tell which kind of African elephant each plundered tusk came from.

Still, Roca said, "until China and other countries do something to crack down on the ivory trade," Roca said, "all the forensics in the world aren't going to stop elephants from being poached."

For more great nature science stories and general news, please visit our sister site, Headlines and Global News (HNGN).

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Bat Super Sensors Make Them Expert Fliers

(Photo : Johns Hopkins University)

Bats are known for their breathtaking precision when it comes to flying and avoiding obstacles, and new research credits their expert flying skills to super sensors found in their wings.

Bats are the only mammals capable of true powered flight, able to reach speeds of 7 to 20 mph with the sort of aerial maneuverability that we wish we could design.

According to a paper published in the journal Cell Reports, the sense of touch plays a key role in powered flight for these mammals. Their highly sensitive touch sensors respond to even slight changes in airflow, and send this information to neurons in the brain. This enables bats to make split-second flight control adjustments.

"Until now no one had investigated the sensors on the bat's wing, which allow it to serve as more than a propeller, a flipper, an airplane wing or any simple airfoil," neuroscientist Cynthia F. Moss, from Johns Hopkins University, said in a statement. "These findings can inform more broadly how organisms use touch to guide movement."

During the study, Moss and her colleagues observed the big brown bat, a common species found throughout North America. The team found that over the course of evolution, bat wings developed in a way that not only enhanced their control during flight, but also allowed bats to use their wings to climb, cradle their young and capture insects.

It turns out that these flying mammals have clusters of sensory receptors at the base of tiny hairs in their wings. So mid-flight, thanks to the location of these touch cells, bats can sense changes in airflow as air ruffles the hairs.

During the study, when the researchers stimulated these hairs with brief air puffs, neurons in the bat's primary somatosensory cortex responded with brief, but precisely timed bursts of activity, suggesting this circuitry helped guide bats during flight.

The team also found that the distribution in and supply of nerves to bat wings is unlike that of other mammalian forelimbs. Surprisingly, neurons in the wing skin connected not only to the higher parts of the spinal cord where forelimbs typically connect, but also to lower parts of the spinal cord that would normally only innervate an animal's trunk.

Evolution made it so that bats can fly with breathtaking precision and avoid crashing into things (although it is hard for them to distinguish between wind turbines and trees). Nonetheless, these findings provide insight into how bats use sensory information to fly with precision in the dark and catch prey midair.

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