Some Wasps Developed Better Vision to Recognize other Wasps’ Faces

In 2011, Elizabeth Tibbetts and Michael Sheehan published a study in the journal Science on how some paper wasps learn and recognize the colorful facial patterns of other wasps in the colony, just as humans recognize others people’s faces.

Now they have published new research in the journal Biology Letters that shows that some paper wasps — those that have variable facial patterns recognized by other wasps in the nest — have more acute vision relative to their size than do wasps without variable facial patterns.

“We found convincing evidence that the wasps evolved better vision for the purpose of telling one another apart,” said Dr. Sheehan, a postdoctoral fellow at the University of California, Berkeley. “This is consistent with the idea that hearing, smelling, seeing or other sensory capabilities in animals, including humans, may have evolved in response to communication signals like we see in the wasp.”

The paper wasps with variable facial patterns are mostly species in which several queens sometimes cooperate to establish a colony, which would make the ability to discriminate among individuals important, he said. Depending on the species, wasps have evolved facial markings that act either like name tags for individual recognition, or like karate belts that indicate a queen’s strength.

“Larger facets in their compound eyes mean better vision, but we found that as these wasps get smaller, they have larger than expected eyes,” Sheehan said. “This demonstrates that they evolved improved acuity relative to size in order to discriminate among different individuals in the colony.”

Like all insects, paper wasps have compound or faceted eyes, each a cluster of thousands of small, telescope-like omatidia with an outer lens that focuses light onto sensory cells inside the eye.

Compound eyes are great for detecting motion — hence a fly’s ability to dodge a swatter — but they provide poor resolution, though larger diameter lenses collect more light and generally provide sharper vision. Many flying insects have a high-acuity zone within the compound eye outfitted with larger diameter lenses and typically facing forward.

Sheehan reasoned that if patterns on the face were important for wasp social interactions, then natural selection might favor wasps that see better, and the lenses in the high-acuity zone on smaller species would be disproportionately larger.

That is what he found when surveying 19 different species of paper wasp in the genus Polistes, half of which were caught in fields around the East and the Midwest, and half obtained from museum collections, some of which were more than 100 years old. While the largest lenses on the eyes of big wasps were the same size — whether or not the wasps could recognize facial patterns — smaller wasps differed. Those with variable facial patterns had larger lenses in their acute zone than those that do not have variable faces.

“This doesn’t overturn evolutionary dogma, but extends the idea that feedback from the environment — in this case, communication signals among members of the same species — can drive change in our senses,” Sheehan said.

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Snails Are Dissolving in Pacific Ocean

An increasingly acidified Pacific Ocean is dissolving the shells of tiny marine snails that live along North America’s western coast. The broad finding, which has surprised some researchers, suggests that sea life is already being affected by changes in the ocean’s chemistry caused by rising carbon dioxide levels in the atmosphere.

“It really changes the game” by demonstrating that acidification is having a noticeable impact, says biological oceanographer Jan Newton, co-director of the Washington Ocean Acidification Center at the University of Washington, Seattle. Newton was not involved in the study.

The researchers studied one kind of pteropod, common planktonic snails known as sea butterflies for the winglike body parts that help them glide through the water. Like other shellfish, pteropods use dissolved carbonate in seawater to build their shells. But laboratory studies have shown that the process can be disrupted, and shells can dissolve, as seawater becomes more acidic, or lower in pH. (Temperature has an impact, too.) As its concentration rises in the atmosphere, carbon enters the ocean through chemical reactions, causing its pH at the surface to drop by 0.1 units since the preindustrial era. That’s raised fears that marine ecosystems could be affected.

Outside the laboratory, however, just a handful of studies have linked falling pH levels to damaged shells. In 2012, researchers documented damage to oysters in hatchery tanks in Oregon fed with seawater that had become more acidic as a result of offshore upwelling patterns. The same year, researchers reported that pteropods collected at one site in the Southern Ocean around Antarctica showed signs of shell damage.

To gauge how acidification might be affecting the Pacific, biological oceanographer Nina Bednaršek of the National Oceanic and Atmospheric Administration (NOAA) in Seattle and colleagues collected pteropods at 13 sites during a 2011 research cruise between Washington and southern California. Back at the lab, they used a scanning electron microscope to examine the fragile shells, which are 1 cm in size or smaller. Normally, healthy pteropods have smooth shells. But more than one-half of these shells showed signs of dissolution, they report in the Proceedings of the Royal Society B. The pitted textures made them look like “cauliflower” or “sandpaper,” Bednaršek says.

“I was surprised by the sheer spacial extent of the dissolution,” she says. “This is something we have not predicted before -- the extent of the population that’s already affected.”

What’s not clear from this study is how such damage might be affecting pteropod populations or the broader ecosystem. Previous work has suggested that shell damage can make it harder for the invertebrates to fight infection, maintain metabolic chemistry, defend themselves against predators, and control buoyancy. And while the snails are one of the most abundant organisms on Earth, “their role in ecosystems is generally not all that well known,” writes biological oceanographer Gareth Lawson of the Woods Hole Oceanographic Institution in Massachusetts in an e-mail. But “they can be important prey items at some times and places” for fish and other creatures. For example, the pteropod examined in this study, Limacina helicina, is a key food for fish eaten by pink salmon, an important North Pacific fishery.

If the pteropod shells “are dissolving as fast as the authors claim, the effects on individual physiology, behavior, and fitness, and hence on populations and food webs, are not easy to predict,” Lawson says. But they “could be profound.”

The waters probed during this study, known as the California Current, are a hot spot of ocean acidification because of coastal upwelling, which brings naturally acidic waters to the surface, where they are made even more acidic by greenhouse gas pollution. But Richard Feely of NOAA, a co-author on the study, says that the site serves as a “harbinger” for what global seas will be experiencing decades hence.


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Rare Goblin Shark Caught in Gulf of Mexico

Commercial fisher Carl Moore wasn’t sure what he had netted last week just south of Key West, Florida (map), when he saw the fish’s flat, blade-like snout. Only after the Georgia angler photographed and released his catch was its identity confirmed: It was a goblin shark, a rare deep-sea shark, and it’s believed to be only the second such specimen ever caught in the Gulf of Mexico.

These sharks are so rarely encountered that any information about them is eagerly devoured by researchers, says John Carlson, a research biologist for the U.S. National Oceanic and Atmospheric Administration (NOAA) Fisheries Service. After Moore examined his curious catch and took a series of photos of it, he released it back into the ocean and contacted NOAA. Moore’s photos were referred to Carlson, who specializes in sharks and was excited to get more data on this rare one.

“We don’t know how long they live; we don’t know how often they reproduce, or even how big they are when they reproduce,” Carlson says. “They’re a mystery.”

Moore had told NOAA he thought the shark he released was about 18 feet (5.4 meters) long. When Carlson and colleagues analyzed Moore’s photographs, they gauged the length to be more like 15 feet (4.5 meters) long. And they made an educated guess about the shark’s sex.

Carlson says male sharks have external sexual characteristics called claspers, two fin-like appendages near the tail that males use to hold on to females while mating. “From the photographs, we don’t see those, so we’re suspecting it’s a female,” he says.

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Game of Thrones Dogs in High Demand

Thanks to the hit HBO series ““Game of Thrones”, a certain breed of dog local to the U.K. is receiving a lot of attention and is in very high demand.

The Northern Inuit, which is the breed used for the scenes with the Stark kids and their dire wolves in the first season,   actually resembles a mix between a malamute and a German shepherd. The breed was founded during the 1980’s by Edwina “Eddie” Harrison, a breeder based in the U.K. these huge dogs are commonly mistaken as a wolf hybrid, which caused an uproar when they first became available as pets. However, the breed is actually mixed with a number of different rescue dogs like the Siberian husky, German shepherd and Alaskan malamute.

This resulted with a dog that looks like a wolf. This beautiful breed, thanks to their different genetic bases, makes them good pets. They’re very loyal, affectionate and friendly. They’re grate around kids, which is one of the reasons why they were used for the Game of Thrones scenes.  They don’t make a lot of noise and are pretty docile. They’re intelligent and easy to train. Finally, they can easily get along with other animals, even other dogs.

The down side of owning a Northern Inuit is that they don’t do well when left alone too long. They’re prone to separation anxiety and can stand having to wait for their owners to come back home. They’re very active, so taking them out for exercise frequently is needed.  And they’re diggers, so don’t expect to see flowerbeds survive with these dogs around as pets. 

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ScienceShot: Butterflies Sip Crocodile Tears

Never smile at a crocodile—or sit on its face and drink its tears. Yet that’s exactly what ecologist Carlos de la Rosa spotted a butterfly and a bee doing this past December as he boated down Costa Rica’s Puerto Viejo River.

In one encounter (pictured above and caught on video), the spectacled caiman (Caiman crocodilus) placidly sunbathes on a fallen tree trunk as a Julia butterfly (Dryas iulia) and a solitary bee (Centris sp.) flutter around its face and taste its tears. The brave bugs’ tear-sipping behavior likely provides salts and proteins scarce in the tropics, de la Rosa writes this month in Frontiers in Ecology and the Environment. Scouring online photographs snapped by amateur photographers and other researchers, de la Rosa was surprised to find ample evidence of insects supping tears from crocodiles and other reptiles such as tortoises. He now thinks the practice may be more common than scientists once thought—just rare to witness.

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Frozen Frogs in the Arctic

When you hear arctic animals, you most likely would think of something big with really thick fur and giant paws or antlers. But oddly enough, you can actually find a creature that looks so fragile and sensitive that it’s better of leaping on lily pads in a pond.

There is a type of wood frog known as the Rana sylvatica which lives in the colder areas of North America. These frogs are seen all throughout Georgia to Canada and even to the Arctic Circle. What makes them so special is that they have an ability to freeze themselves during the really cold seasons and thaw out when the warmer seasons come in.

Numerous studies have been done on these frogs extreme ability on freeze tolerance over the past 25 years, but a notable one is by the Department of Zoology at Miami University in Ohio led by Jon Costanzo. He wanted to learn more about how the Rana sylvatica could stand the freezing and the chemical and physiological factors that comes with it.

However, the Rana sylvatica is not the only animal that could actually survive the extreme cold. There are other reptiles, insects and even marine species that thrive in ice cold environments. However, only a number of these creatures have the Rana sylvatica freezing abilities. These small amphibians can basically survive for a number of weeks even when most of the water content in their bodies is completely frozen. They turn into solid frogsicles under their frozen state during winter. 

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African Bird 'Cries Wolf' to Steal Food

Fork-tailed drongos, glossy black African songbirds with ruby-colored eyes, are the avian kingdom’s masters of deception. They mimic the alarm calls of other species to scare animals away and then swipe their dupes’ dinner. But like the boy who cried wolf, drongos can raise the alarm once too often. Now, scientists have discovered that when one false alarm no longer works, the birds switch to another species’ warning cry, a tactic that usually does the trick.

“The findings are astounding,” says John Marzluff, a wildlife biologist at the University of Washington, Seattle, who was not involved in the work. “Drongos are exceedingly deceptive; their vocabularies are immense; and they match their deception to both the target animal and [its] past response. This level of sophistication is incredible.”

Since 2008, Tom Flower, an evolutionary biologist at the University of Cape Town, has followed drongos in the Kuruman River Reserve in the Kalahari Desert. He’s habituated and banded about 200 of the robin-sized birds, and, using food rewards, has trained individuals to come to him when he calls. After getting its snack, the drongo quickly returns to its natural behavior—catching insects and following other bird species or meerkats—while Flower tags along.

Drongos also keep an eye out for raptors and other predators. When they spot one, they utter metallic alarm cries. Meerkats and pied babblers, a highly social bird, pay attention to the drongos and dash for cover when the drongos raise an alarm—just as they do when one of their own calls out a warning. Studies have shown that having drongos around benefits animals of other species, which don’t have to be as vigilant and can spend more time foraging. But there’s a trade-off: The drongos’ cries aren’t always honest. When a meerkat has caught a fat grub or gecko, a drongo is apt to change from trustworthy sentinel to wily deceiver. In a previous study, Flower showed that the birds get as much as 23% of their daily food by emitting a false alarm and then stealing their victim’s meal. The meerkat that’s just caught a gecko, for instance, is likely to drop it and run for the nearest burrow when it hears a drongo’s alarm—whether true or false.

Drongos also imitate the alarm calls of numerous other species. Altogether, the birds can make as many as 51 different warning cries. Six are those that drongos themselves use to announce the presence of various types of predators; the other 45 are the alarms of other species. And all the species—including the meerkats and babblers—know and pay attention to one another’s warning calls, Flower says. “They’re all eavesdropping on each other. It’s like they speak each other’s language.”

But what benefit do drongos get by imitating the alarm calls of other animals? To answer that question, Flower and his colleagues carried out a series of playback experiments using pied babblers as the target species. The results showed that after hearing a drongo imitate a babbler’s or starling’s alarm cry, the babblers stayed away longer from a foraging area than when they heard the drongo’s warning call. The babblers also ignored alarm calls after they’d heard one type three times in a row. But when the third call was a warning that they’d not previously heard, they took flight. The experiments show that “it pays for drongos to have large alarm repertoires, to use their target’s alarm call, and to vary their calls,” Flower says.

Which is exactly what the birds do. By following 42 marked wild drongos, he and his colleagues observed 151 occasions when the birds repeatedly attempted to steal food from the same victim. In 74 of these attempts, the birds changed the type of alarm they were using. They were most likely to do so, the scientists found, when one type of false call didn’t do the trick. Moreover, when a drongo changed its call, it was more likely to succeed in stealing its target’s food, the team reports online today in Science.

“The drongos are producing their calls tactically. They’re changing their calls in response to the feedback they get from their target,” Flower says. “And that’s how they’re able to overcome the problem of crying wolf too often.”

“The birds’ tactical deception must reflect sophisticated cognitive abilities,” says Karl Berg, an ornithologist at the University of Texas, Brownsville, who was not involved in the work. Indeed, Flower and his colleagues note that some might be inclined to see the birds’ talent as suggestive of something like “theory of mind”—the ability to intuit what others are thinking, a skill that has definitively been found only in humans.

But Dorothy Cheney, a primatologist at the University of Pennsylvania, says that “simpler explanations,” such as associative learning, “are more likely” to explain “what the drongos are thinking when they produce their deceptive calls.” For example, she notes, it’s possible that drongos have learned two behavioral contingencies: “One, targets flee when they hear alarm calls,” and “Two ... switch alarm call type if the previous call failed” to send the victim fleeing. At the very least, the birds seem to have an understanding of cause and effect, notes Flower, who is now working on a new study to try to nail down what goes on in a drongo’s head.

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Pokemon Comes to Life

The popular cartoon show Pokemon has captured the imagination of generations of people with their monsters and creatures that look like a mixture of two or three different animal. However, some creatures featured in the TV show resemble real life animals that fans are wanting to get them as pets.

Pictures of axolotls, which are commonly known as Mexican Walking Fish, became viral on the internet because of their very close resemblance of the pokemon Mudkip. These animals have actually been bred in captivity and have been sold as pets for years. Although most people call them fishes, they’re actually amphibians. These animals are salamanders under the order Caudata/Urodela. They’re more closely related to frogs compared to fishes. Another common misconception about these animals is that they’re reptiles or lizards. However, amphibians are actually a whole different thing. Salamanders might resemble lizards, however they are a very different thing.

Captivity breed axolotls come in a variety of colors, including white albino, golden albino, leucistic or white with black eyes, different shades of brown, gray and the ever so popular blue. Other varieties also have solid colors like the melanoids which are nearly all black. Wild axolotls commonly are colored between the color rage of cream, brown or black. Some specimens also have a mixture of two or more colors.

They’re best placed in a cold environment. Lower temperatures may result to slower metabolism while higher temperatures could cause them stress and an increased appetite. They’re commonly feed salmon and trout pellets, live or frozen bloodworms, waxworms and earthworms.

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Flying Snakes in the Jungle

The last thing you would imagine to see flying in the air is something you’d normally slither around the ground, like a snake. A flying snake sounds like something out of a nightmare, but there is an actual type of snake found in the southern areas of Asia that does just the thing.

Flying snake, also known as Chrysopelea, doesn’t actually have wings like a bird. They’re misnomers that glide through the forest by jumping off on tree to another, shifting their bodies during free fall to catch air and gain lift. In the past, these snakes were looked at as parachuters, but recent studies on their physical structure showed how their tube-shape and lack of limbs help them glide through the air. 

To lift off, a Chrysopelea would slither off to the end of the tree branch, dangle out to a J shape and then propels itself into the air by forming an S shape. Once in the air, it positions itself into a C shape which helps traps the air and let it glide. It can even turn different direction while gliding. It’s complex way of setting off and moving around in the air technically makes them better gliders compared to a more popular gliding animal, the flying squirrel.

There are 5 known flying snake species, all found in the western India until the Indonesian area. Not a lot of things are known about these snakes and how they behave in the wild, but they’re said to spend most of their time off the ground and on the trees. In fact, they rarely leave the canopy.  They can grow from 2 to 4 feet in length. 

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Why Chinchillas are Great Pets

Most of us have had hamsters for pets as kids, but there’s another animal, that’s similar to a hamster, that you should consider getting your kids as their first pet.

The chinchilla is a cute rodent that originated in the mountains of South America. These animals are marked as critically endangered in the wild however, they have grown a lot of popularity as house pets over the years. A number for pet stores actually offer them and they’re being breed in captivity. 

Here are a few reasons why these furry little creatures make great pets.

Low-Maintenance is their Middle Name

What makes these animals perfect for new or first time pet owners is that they’re very easy to take care of. They love to play, especially with their fellow chinchillas. They just need to be well-fed, a wheel is enough for them to exercise on and they’re not really prone to common certain illnesses. They do prefer a cooler place to stay in, so you might want to crank the air-conditioning up during summer.

They’re Very Social

In the wild, chinchillas live in groups. As pets, they love the company of their owners and other people and chinchillas to play with.  They’re usually very timid, except during dawn when they’re very active, and they act like kids in the way that they always want to play. 

They don’t Smell

Unlike the common hamster, chinchillas are actually very clean. They do poop frequently, but their poop is usually odor-free and dry, making it easy to clean. Like cats, they care a lot about their personal hygiene and clean themselves as often as they can.

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