infoanimals

Straw-colored Fruit Bat (Eidolon helvum) 

First off I just want to say how much I love this picture. Anyhoo, a little about the species! As their name suggest, these African bats feed on fruit- and they undertake quite a journey to find enough to fill their quotia. The bats follow the annual rains north through sub-Saharan Africa before returning south at the end of the rainy season. Their extensive migration takes them hundreds of miles. Along the way, they spend the day in large, noisy colonies in tree roosts. At night they leave their roosts and venture out to find fruit, where the colony doesn’t stay as closely packed as they do when roosting. The giant population of straw-colored fruit bats play a key roll in pollinating and dispersing the seeds of many plants. Just another example of how everything in nature is connected! Photo credits to Kieran Dodds

Male sharks have claspers, organs which function like a human penis. Before mating, sea water is taken into a pair of muscular sacs which lie along the male’s ventral side. The sacs contract and flush sperm into the female. Mating can be a rough affair…literally. Female sharks are often scarred as a result of the bites inflicted by their partners during mating. The male bites the female on her flank, back, and pectoral fins to maintain his position and in some cases, make her receptive. With a firm grip from behind, the male inserts one of his claspers into the female’s cloaca, which is equivalent to a female vagina. Sharks are born three different ways, depending on species. Oviparous sharks lay eggs protected by rough cases, known as a mermaid’s purse. The mother leaves the pups to fend for themselves. Viviparous sharks birth live young, and the babies are born ready to defend themselves. Ovoviviparous sharks store the egg cases inside the mom, where they grow. The young feed off a yolk sac. In some shark species, the first pup to hatch will eat the other eggs before they have an opportunity to hatch. The picture above shows two blacktip sharks biting in a mating ritual. Photo credits: sharkinformation.org

Inverts! Yay! The peacock worm lives in a muddy tube that extends from the seabed. It constructs the tube itself, secreting mucus and binding it with sand and mud. To feed, the worm comes to the mouth of its tube, extending fans of finely divided featherlike tentacles into the water. The worm waves its tentacles to trap material suspended in the seawater, including grains of sediment and plankton. It sorts its catch using the tiny hairlike structures, called cilia, that cover its tentacles. Edible particles are transported toward the mouth to be consumed, while larger, inedible particles are added to the tube that surrounds the worm. Neat right? By adding materials to their tubes as they filter the sea water around them, peacock worms are able to increase their height. If threatened, the worm will quickly disappear into the safety of the tube. Photo credz to Sue Daly

With fewer than 2500 individuals left in the wild, the black rhinoceros (Diceros bicornis) is regarded as one of the most endangered animals on Earth. Native to Africa, the rhino lives in the vast savanna grasslands, feeding on grass and small shrubs. There are currently four recognized subspecies of the black rhino. Although the habitat of rhinos is being reduced by agriculture, it is poaching that poses the greatest threat to this majestic animal. Some cultures believe that the powdered horn of the black rhino is a cure for numerous diseases and is thus highly sought after. I’m mediocre at distinguishing between black and white rhinos, so if the picture is of a white rhino, please feel free to correct me! Picture source at dailypictures

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Bottlenose Dolphins // Brandon Cole

Featured in art both ancient and modern, films, TV, and in aquarium shows worldwide, the Bottlenose Dolphin is likely the species most familiar to people. It is larger and more powerfully built than many other members of the family Delphinidae, but size, shape and color vary widely on an individual basis and according to location. It has adapted to an amazingly wide range of habitats including coastal reefs, bays, estuaries, river mouths, and open ocean atolls around the world from nearly 60 degrees North to 50 degrees South latitude.

Tursiops truncatus is obviously an acrobatic species capable of powerful jumps, often curious towards people, and a regular bow-rider of boats. Most are varying shades of gray, with a stout broad beak and prominent dorsal fin. Males are larger than females. Studied carefully both in captivity and the wild, we know more about the reproductive biology of this species than that of most other oceanic dolphins. Gestation lasts nearly a year, 3-4’ long calves are born year round, and young are not fully weaned until 18 or 20 months old.

Depending on location, diet varies considerably, and some populations of Bottlenose Dolphins have developed special feeding behaviors: sometimes cooperating with, sometimes stealing from, commercial fishermen; chasing fish up onto shore; hunting deepsea fish to 1500 feet deep.

Overall, the general outlook for this species is relatively positive, though certain local populations face problems with pollution, hunting (thousands are still killed each year for food or bait), habitat loss, gillnet entanglement, and food depletion.

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Atlantic Spotted Dolphins // Brandon Cole

I’ve snapped tens of thousands of pictures in hopes of capturing on film the magic of an encounter with wild dolphins. An impossible quest. But I keep trying, and I always look forward to my next trip to the Bahamas. For it is these clear, warm waters north of Grand Bahama Island where dolphinfans from the around the world have been swimming with a pod of wild Atlantic Spotted Dolphins (Stenella frontalis) for over 20 years. When in the mood to play, they wait for us to jump in with mask, snorkel, and fins. I have come to recognize many individual dolphins by their unique markings and personalities, and have watched half-meter newborns grow up to raise babies of their own.

Secretly, I like to think that they in turn recognize me each year, the laughable human with ever-present camera, awkwardly blundering along in a hopeless attempt to match their fluid mastery of sea. The dolphin’s permanent smile says it all, however- the joke’s on me.

Usually found in groups of 5 to 15, Atlantic spotteds occasionally congregate in larger groupings numbering a few hundred. Appearance varies greatly between different stocks throughout their range, and based on the dolphin’s age. In general, a calf is born unspotted, and as it matures spots develop and increase with age. At 20 to 30 years, some individuals have an almost completely “fused” pattern of spots.

Range overlaps the similar Pantropical Spotted Dolphin, Stenella attenuata, but S. frontalis has a more robust body and tends to be more oceanic. Though little is known about their reproduction, females nurse calves for 3 to 5 years, so it’s possible for a mother to be both pregnant and lactating simultaneously. Like most dolphins, play between pod members is an important social exercise. Interaction with other species, such as bottlenose, is not uncommon. Juvenile spotted oftentimes are witnessed engaging in homosexual sex play. 

Here’s something interesting- a fluke print! A fluke print is the smooth oval-shaped patch of water a whale leaves after fluking. The prints are caused by the up-welling of water displaced by the movement of the tail. It’s also called an oil slick, however it’s simply caused by the power of a whale’s cuadal area. Researchers can track the fluke prints to follow a whale who has gone underwater and may not surface again for many minutes.  Fluke prints are also used to spot individuals during whale watching tours- however, when you’re close enough to see a fluke print, usually you’d have already seen the blow a couple miles away. Photo by OneMansWonder

Cassidinae, aka tortoise beetles, are any members of more than 3,000 beetle species that get its name from its transparent carapace. Tortoise beetles respond to danger by withdrawing the head and feet like a tortoise and sealing their flat-edged shell to a leaf. Many tortoise beetles can change color at will by squeezing a film of water underneath their shells. Cassidinae are one of the few groups of arthropods where the females create papery ootheca to protect their eggs. The ootheca often have the mother’s feces placed on top of them for extra camouflage. This is my favorite tortoise beetle, the spotted tortoise beetle (Aspidomorpha miliaris)! Photo by WJ.

This beauty is called the marbled polecat (Vormela peregusna) and as its name suggest, the marbled polecat has a black coat mottled with white or yellow spots and stripes. A distinctive black mask over its eyes characterizes its face, while its underparts are black. It has a long, sinuous body with short legs and a small, flat head with a blunt snout. When threatened, the marbled polecat curls its tail to display its warning coloration and emits an unpleasant odor. The marbled polecat enlarges rodent burrows to makes its den, and hunts at night, dawn, and dusk. They are solitary animals with a gestation of 56-63 days, and litter size ranges from 4-8 cubs. Nothing is safe from this mustelid, which eats a wide variety of rodents, hares, birds, lizards, fish, and even insects. This species is threatened by habitat loss and depletion of steppe rodents, one of its main foods.

Photo by Dark-Ness85

A sea star consists of a central disk, which 5 to 20 or more arms (also called rays) are attached to. On the underside of the disc is the mouth. The endoskeleton are made of calcareous plates that allow movement in the rays. Tiny pincer-ish spines called pedicellaria are located near the skin gills. These keep the sea star free of debri and even the larvae of other marine organisms. 

Most sea stars are carnivorous. Mollusks, annelids, and crustaceans are top ‘o the menu, but some sea stars even consume other echinoderms. Sea stars can’t make a quick ambush when chanced with a possible meal due to their water vascular system, but since they usually prey on slow-moving or stationary organisms, speed of attack isn’t needed for a full stomach.

Shown here is a Blue Sea Star, Linckia laevigata (Class Asteroidea) of Indonesia. Photo by Reinhard Dirscherl

Who knew the Arctic Fox (Vulpes lagopus) was such a voracious predator? They hunt and eat animals such as lemmings and Arctic hares in the warmer months, but in the winter, when prey is scare, not only will they attack young seals in their dens, but they will also scavenge carrion left by larger predators like polar bears! Wicked, right! The key to their success is that they are very adaptable and can even survive by eating birds’ eggs and plant material, like berries, if need be. On the seashore, dead fishes, washed up seals, and also shellfish and sea urchins aren’t safe from these carnivorous canids. 

To locate prey hidden under the snow, the Arctic Fox listens carefully for the sounds of borrowing or movement. It rears up in the air with its eyes focused on a spot on the snow above its victim. And then it leaps! At the peak of its jump, the fox extends its front legs and rotates its body forward. Then it plunges head-first toward the ground and thrusts its front paws through the snow into its victims lair beneath. 

But these amazing animals just don’t stop there. Arctic Foxes aren’t only adaptable in their eating habits, but their living conditions, too! They dig dens in deep snow and can survive in extremely cold conditions of -50° Celsius, protected by their thick fur and a layer of body fat. A counter-current heat-exchange system in the legs ensures that blood returning to the body from the feet is nice and warmed up. This means that, although the feet aren’t as warm as the rest of the body, heat won’t be lost from the core. And you know what else is cool about an Arctic Fox’s paws? They have fur on the bottom of their feet for walking on the slippery ice!

The coat of the Arctic Fox changes from its brownish gray in summer, to blend well with the color of rocks and low-growing vegetation, to pure white in winter, providing really awesome camouflage against the blinding snowy background. In addition, the fur grows much thicker in winter to insulate the fox against the icy cold of the Arctic tundra. When resting, the fox covers its face with its bushy tail. 

Kickass photo by Paul Williams

Some might say this is gross but marine biologists know this as utter baddass. It’s a parrotfish in a mucus cocoon! A few species of parrotfish slumber tucked away in coral crevices to avoid nocturnal predators, with a significant advantage…a snot shield! Not really snot but still. It can take half an hour to secrete the mucus from special glands in its opercular cavity, the protective chamber containing the gills. On contact with water, the mucus swells and becomes gelatinous. Most predators hunt by smell, and this sleeping bag of slime stops them from detecting the parrotfish scent. Crustaceans hunting by touch are also deterred. I’d say the mucus cocoon is a pretty neat thing, since other species of parrotfish dive under the sand but risk being unearthed by dolphins using echolocation. Photo by Stephen Frink

Aren’t otters adorable? As large as a medium sized dog and weighing nearly the same, sea otters snooze close to shore while floating gently on their backs and are anchored firmly in place by means of a kelp plant. But alas, life isn’t easy for the sea otter (Enhydra lutris) who have such a high metabolism that they need to eat 25% of their body weight per day. This is a considerable feat, since their prey lies on the sea floor up to 100 feet below them. Their energy is also spent grooming their fur, an essential task as it is their only protection against the cold water of the beautiful Pacific. When you shift your fingers through your dog’s fur/hair, you eventually reach skin- not with otters.  Sea otters have the thickest fur of any mammal, with up to one million strands per square inch! Lacking any blubber, they rub natural oils into their fur and fluff it up to trap air bubbles. It’s an awesome insulator ‘cause of its high density. Otters help the ecosystem, too. Without them, urchin populations would grow so large that the kelp forests-home to thousands of animals- would be decimated. Otters are a very precious keystone in the environment. In their glory days, as many as 20,000 sea otters lived along the Pacific coast, before greedy humans got their hands on them. Now populations are making a comeback, but not without our help. Thanks to the Monterey Bay Aquarium’s SORAC program, nearly 500 injured sea otters have been rehabilitated and released back into the wild. Now here’s a picture of Pup 572, MBA’s newest otter pup, who’s being raised by Joy. I loved getting to see and interact with them, they’re really a huge bundle of love! 

Talkative Marmoset Monkeys Take Turns

Posted by Mary Bates in Weird & Wild on October 18, 2013

Marmosets share a unique characteristic with humans: In conversations, these social monkeys wait their turn to speak.

During exchanges, which can last up to 30 minutes, marmosets engage in vocal turn-taking and they don’t interrupt each other, researchers from Princeton University report in Current Biology.

“We were surprised by how reliably the marmoset monkeys exchanged their vocalizations in a cooperative manner, particularly since in most cases they were doing so with individuals that they were not pair-bonded with,” said Asif Ghazanfar, one of the study’s authors, in a news release. “This makes what we found much more similar to human conversations and very different from the coordinated calling of animals such as birds, frogs, or crickets, which is linked to mating or territorial defense.”

Talk to Me

Ghazanfar and his colleagues looked at marmosets because of what they have in common with humans—they are extremely social and talkative primates.

In the study, they placed marmosets in opposite corners of a room and then separated them with barriers. The barriers blocked their sight, but not the sounds, of the other monkeys. In this situation, the marmosets made a specific kind of contact call known as a “phee” call.

Marmosets took turns calling, waiting about 5 seconds after their partner was finished to respond. And if one marmoset slowed down or sped up the rate of its calls, its partner tended to do so, as well.

These results suggest marmosets, like humans, follow simple rules in their conversations.

Conversation Starters

For marmosets, there are several advantages to being polite conversationalists. If a monkey is separated from its social group, exchanging contact calls brings comfort. And taking turns calling could let your conversation partner know that you are listening.

In their contact calls, marmosets also convey information about their gender, identity, and social group. Vocal turn-taking could allow marmosets to fully extract all this information, especially in noisy forest environments.

The researchers say marmoset vocal turn-taking may represent a basic foundation upon which more sophisticated forms of communication arose in humans.

Eavesdropping on the conversations of this tiny, talky monkey could shed light on the roots of human communication — and maybe inspire us to be more polite conversation partners.

 Photograph by Visuals Unlimited, Corbis

Animal Pharm: What Can We Learn From Nature’s Self-Medicators?

Birds do it. Bees do it. Butterflies and chimpanzees do it. 

These animals and many others self-medicate, using plants and other surprising materials to improve not only their own health but also the health of their offspring.

video of capuchin monkeys at the Edinburgh Zoo shows them rubbing onions and limes on their skin and into their fur as an antiseptic and insect repellent. Biologists have noticed that parasite-infected female monarch butterflies are more likely to lay their eggs on anti-parasitic milkweed, giving their offspring instant medication, while uninfected females show no preference. And urban birds who incorporate cigarette butts into their nests may be doing so because chemical properties in the smoked cigarettes may repel parasites, according to a 2012 study.

While cigarette-butt wallpaper may not appeal to most of us, other ways that animals self-medicate might be worth watching. Mark Hunter, a University of Michigan ecologist who was involved in the monarch research, says there is plenty to be learned from observing the way animals use the entire outdoors like one big drugstore. It’s something our own species probably once did—and might do well to revisit with modern pharmaceutical engineering and computer modeling techniques.

“It’s not the only way, but it seems to me that a sensible way [to aid in human drug development] would be to watch what animals do in nature to see how they exploit the natural products, the pharmaceuticals that are available to them in the environment, and try to learn from them,” he says.

Earlier this year, Hunter spent time with people of the Shangaan tribe in South Africa.

“If you go for a walk with somebody, every plant you pass has a cultural or medicinal significance, and many of those have been learned from watching animals,” Hunter says. The bark of the black monkey thorn tree, for example, is used as a stomach medication, a choice based on watching how elephants behave.

Diverse “Doctors”

Not long ago primates were thought to be the only animals smart enough to self-medicate. Mark Bowler, the San Diego Zoo Global Institute for Conservation Research postdoctoral fellow who made the capuchin video, says that chimpanzees use a range of medicinal plants, “including some that have a physical, not chemical action: They swallow wads of hairy leaves whole, and the leaf hairs appear to physically ‘brush’ certain parasites out of the gut. I tested some of this with Edinburgh Zoo’s chimps, and they seem to do it spontaneously—no learning process involved.”

The capuchins’ behavior in the video—rubbing the body with a particular chemical or scent—is called “anointing,” and other animals do it, too. Bowler is currently studying whether anointing behavior in some other primates is scent-marking or something else, but says that at least in capuchins, the purpose appears to be self-medication. Anointing can also be a form of self-defense: Ground squirrels chew rattlesnake skins and then lick their fur, a trick likely to deter that particular predator.

Insects have been found to be prolific self-medicators, too. Take the arresting case of the fruit fly Drosophilia melanogaster, which uses alcohol to protect itself against parasitic wasps. The wasps lay their eggs in the fruit fly larvae; the developing wasp grubs will eventually eat the flies from the inside out and burst forth from their dead bodies.

Larvae that consume high doses of alcohol from fermented fruits, however, are less likely to be infected—and if they are, the invading wasp grubs die quite nastily with their internal organs being ejected out of their anus. Moreover, fruit fly mothers who see female parasite wasps nearby will give their young instant protection by laying their eggs in alcohol-soaked environments—which means they see and remember their nemesis. (Related: “Flies Use Alcohol to Protect Their Young From Body Snatchers.”)

“Not a bad defense,” says Hunter, adding that this demonstrates the idea that “the cost we’re willing to pay for a medicine depends on the consequences of not using it.” While the alcohol isn’t necessarily good for the flies (though some species of Drosophilia melanogaster show a resistance to its ill effects), the flies will die if parasitized.

“The alcohol has worse effects on the parasites than it does on them. So it’s worth laying your eggs in a high-alcohol environment if it will save your offspring,” he says.

Bee Benefits

Honey bees self-medicate by protecting their home. The bees traditionally “line their nests with resins that they collect from plants, and those resins contain a wide variety of antimicrobial compounds,” Hunter says. The resulting mix of resins and beeswax is called propolis, and it’s been used as a traditional medication for centuries.

But because beekeepers didn’t want to deal with those sticky resins every time they opened a hive, Hunter says this resin deposition may have been selected out of most commercial bee populations over the years. After the bee genome was sequenced, scientists realized that bees have different immune systems than other insects—“probably because they’ve been relying on this resin,” says Hunter. Disease is one of the many suspected causes of bee die-offs, along with decreased plant diversity (and thus fewer places to get resins from) and pesticides, so encouraging propolis collection is probably a good idea.

Do animals learn to self-medicate, or is it pure instinct? Well, plenty of intelligent animals self-medicate, so it’s not always clear. But in the case of the monarch, Hunter points out, the mothers don’t hang around to see what happens to their babies, so there’s no learning involved. In this case, “the only possibility is that it’s a genetically determined behavior. It’s instinct.”

So the next time you’re on your way to the drugstore and pass a monarch hovering around a milkweed, or a bird who seems to have taken up a smoking habit, consider that they might actually be running an errand, just like you.

By Liz Langley on National Geographic.

Monarch butterflies swarm a tree in Sierra Chincua, Mexico. Photograph by Joel Sartore, National Geographic

What are the differences between the mimic octopus and the wonderpus octopus? Surprisingly, quite a lot! But let’s start with the basic facts. Both species are found from Bali to Sulawesi and from the Philippines to Vanuatu. The mimic octopus (T. mimicus) is an octopus species with a unique ability of mimicking other organisms, including sea snakes, giant crabs, and lionfish! It grows up to two feet long. The wonderpus (W. photogenicus) is primarily found in shallow waters and wasn’t formally described by taxonomists up until recently. 

The mimic octopus is primarily diurnal while the wonderpus tends to forage from dawn to dusk. The mimic octopus can be identified by size, coloring, and behavior. Its normal coloring consists of mottled white stripes along the arms and fuzzy “islands” of coloring along the mantle. The mantle is a brownish color. Mimic’s also have a distinct white “v” located on the posterior mantle, which the wonderpus lacks. The eyes are on short stalks and one can find a white outlining along the base of their suckers. They are usually found in shallow waters and is even known to bury itself beneath the sand.

The wonderpus has longer arms than the mimic- it has distinct white bands that wrap almost completely around the arms, whereas the mimic’s usually fade before they make a complete “ring” around the tentacle. The wonderpus also has well defined white spots on the mantle, and the mantle is a rusty brown color. The eyes are on long stalks and the species does not have a white outlining along the base of their suckers. They’ve been found to flash warning colors under distress.  

Can you figure out which species is pictured? ;) Photo by Ricobie.

All seals are mammals, so they need to breathe air. When openings in the sea ice start to freeze over in the fall, ringed seals (Pusa hispida) create breathing holes through the ice, so that they can pop up for air. In the spring, females excavate caves out of snow that has piled up in drifts above their breeding hole, a behavior that is unique among seals. Ring seals give birth to a single pup and nurse the pup for about 40 days. The cave helps the pup survive the extreme cold and protect it from predators. Polar bears can detect the caves by scent and actually will break through the ceiling. An adult seal stands a chance of escape by diving into the water through a breathing hole, but the pup can be easy prey. And this post has been dedicated to Ben :) Picture by Paul Nicklen.

The Heat Is On: Which Animals Will Win or Lose in Climate Change?

Posted by Liz Langley on October 17, 2013

Walrus Worries

Another animal that’s losing out as winters warm up, National Geographic recently reported, is the Pacific walrus, which is losing the ice on which it sometimes hangs out. Actually it’s not called a hangout: When walruses pull themselves out of the water to rest or get warm on ice or land, it’s called a “haul out.” And with less floating ice, they’re gathering on Arctic coast land in larger groups than ever. This kind of togetherness isn’t good for the already-threatened species, as it could increase danger from stampedes and raise the possibility of disease outbreak. Read more on NationalGeographic.com.

 Photograph by Sergey Gorshkov, National Geographic