ANiMAL MUNDi: Stars of the Deep by TheFrogBag

Stars of the Deep

written by Corinna of TheFrogBag

Photos courtesy of So. California Sea Life Center

Humans have always had a hard time naming things that live in the sea. It’s only been in the last hundred years or so that we’ve been able to get a good look at many of them, and this has led to some unhelpful overlap of nomenclature between land animals and sea creatures. 

We have sea horses, sea cows, dog fish and parrotfish, none of which are closely related to any of their namesakes. And then there are starfish, which sometimes superficially resemble stars but are certainly not fish. Brittle stars are at least a little brittle, although they resemble a nest of snakes more than anything celestial.

At least, like starfish, brittle stars are classified as echinoderms so the common name is helpful in that respect. Unlike starfish, they have a small central disk and very thin arms. They also lack an anus, so waste is expelled through the same opening that nutrients enter. But don’t let that fact fool you into thinking that these beasts are primitive. They in fact have five jaw segments and 10 infolds within their “blind” stomachs to aid in digestion. Different types of brittle stars have evolved to eat different things in this way, from detritus to plankton. One species is even specialized to slurp up the mucus of their host coral. 

Who would have thought that such an elegantly named creature could have such disgusting habits?

As highly specialized as brittle stars are, the list of organs that they do without is impressive. They lack brains, eyes, a sense of smell, a sense of taste, and a complex digestive tract. Instead they have a ring of nerves around their central disk with radial offshoots that run to the end of each limb. These limbs are covered in an epidermis that is highly sensitive to touch, chemicals in the water, and even light. This light sensitivity makes it possible for brittle stars to spend most of the day hiding in crevices, emerging only after sunset to feed unobtrusively. 

Despite their cryptic habits predators frequently target them. That’s where the “brittle” part of their nature becomes important, since they can easily lose a limb (much like a lizard can lose a tail) without undue stress. The regenerated “leg” may be shorter than the other limbs, but it will work just as well. 

Limbs aren’t the only body part that these animals can regenerate. Even though most species have separate sexes and reproduce by shedding gametes into the water, a few actually give birth to live young via special brood pouches. But others create new stars by literally splitting in half, a process that seems to belong more to the plant kingdom than the animal kingdom. The result is two less-symmetrical echinoderms (half the body will have short “legs”) where formerly there had been one, but each will have a fully intact set of internal organs and nerves. 

In some species this process may produce 15 new animals in one year!

So, to summarize, brittle stars have no eyes, no brains, and no anus. They’re kind of squishy, but they do break easily. And some of them have unsettling ways of reproducing. 

Maybe we don’t want a more descriptive name for them after all... 

ANiMAL MUNDi: The Climbing Kangaroo by TheFrogBag

The Climbing Kangaroo

written by Corinna of TheFrogBag

Photographs courtesy of www.Arkive.org

The fauna of Indonesia is unlike any other. Birds barter for mates with pretty rocks. Lizards grow to monstrous sizes. Fish crawl instead of swim. And, in some places, kangaroos live in trees.

The Goodfellow’s tree kangaroo (Dendrolagus goodfellowi) is one of these. Also called the ornate tree-kangaroo because of its colorful wooly coat, it rarely ventures to the ground. 

Unlike its better-known terrestrial counterpart, goodfellowi moves slowly when forced to walk on the earth with a top speed of only about five miles per hour. High in the canopy, it’s a different story. With short hind limbs, muscular forearms, and padded, gripping soles on its feet, this is a creature made for climbing. Sharp curved claws propel it upwards while a broad, strong tail acts as a rudder for daring leaps between trees. 

It’s still a kangaroo though, with a marsupial lifestyle to match. The young are carried in a well-protected pouch, safe from falling as mom moves between branches. The babies stay sequestered this way for up to a year, and will continue to nurse for several months even after “fledging”. At two years of age they’re ready to have joeys of their own, and so the cycle continues. 

Nocturnal by nature, tree kangaroos can sometimes be seen at dusk as they emerge to feast on leaves and flowers. Digestion is accomplished with the aid of a scculated stomach since fibrous material would pass too quickly through a smoother gut. At forest boundaries the kangaroos have been known to descend to eat crops and even grass, something that might be necessitated due to their shrinking habitat. 

Logging, mining, oil exploration, and agricultural expansion have all taken their toll on these shy creatures. Hunting burdens them with additional pressures that tree kangaroos can ill afford, and is the main reason they are considered endangered across their range. 

Happily, there is still hope for their survival thanks to a network of nation parkland and their almost total lack of arboreal predators. More direct conservation measures would make a difference though, something that requires more people to understand their plight. 

Want to help? Support sustainably harvested timber. Try to forego palm oil. And tell someone about tree kangaroos today! 

ANiMAL MUNDi: The Tiniest Dragon by TheFrogBag

The Tiniest Dragon

written by Corinna of TheFrogBag

Photographs courtesy of Michigan Science Art

Do you long to live in a fantasy world filled with dragons? To look up and see colorful winged lizards flying overhead? 

You don’t have to bury yourself in Anne McCaffrey novels to make that happen. Just hop the next plane (or steamer, if you’re intent on following the fantasy model) to Indonesia and you’ll be rewarded with real, live dragons. 

Of course, there are a few caveats. The Draco lizard (Draco volans) isn’t really a dragon per se since it’s only about eight inches (20 cm) long. Of that, more than half is tail. Which means there will be no taming this beast for riding or knight-killing. And it doesn’t breath fire. 

Instead it eats ants and termites, something that most homeowners will appreciate as a more useful skill. It also doesn’t really fly so much as glide. That’s because instead of true “wings” these lizards have elongated skin-covered ribs that can’t flap. What they can do is extend or retract, allowing the them to catch drafts of air and float for as far as 30 feet (nine meters), using their tails as rudders to steer them in the right direction.

Despite their diminutive size Dracos are every bit as territorial as their fairytale counterparts. Males will ferociously guard up to three individual trees, using their gliding ability to dive bomb any rivals that dare approach. But since they can’t take off from the ground the way a hawk or even a pigeon can, they confine themselves to the canopy and leave the forest floor between their trees to other animals most of the time. 

The only exception is when a female is ready to lay eggs. She will make the long journey to the ground, dig a hole in the soft leaf litter with her snout, and deposit four or five eggs. She will then guard her nest for a full 24 hours before heading back to the treetops and leaving her offspring to their fate. If they are lucky, the young dragons will hatch before a predator finds them and head up to claim territories of their own. 

Fortunately, a lot of the babies are successful. Dracos are a lot more abundant than one might expect for such an unusual animal. Their arboreal lifestyle keeps them safe from many predators, including humans. They are further protected by the mistaken idea that they are poisonous, a local myth that has somehow become attached to these very real dragons.

ANiMAL MUNDi: The One with the Shoe

The One with the Shoe

written by Corinna of TheFrogBag

Photographs courtesy of Arkive.org

Imagine a carnivorous dinosaur. Give that dinosaur grey-blue feathers, wings, and long stalk-like legs. Got that pictured? Now add a ridiculous boat of a beak to its face, with one ferociously sharp point on the end instead of a mouth full of teeth. What you now have is still a dinosaur (albeit a very modern one) called a shoebill stork (Balaeniceps rex).

Shoebills get their name from their most obvious feature. Other names include the less-than-kind sounding whale-headed stork, bog bird, and abu markub, which means (no surprise here) “the one with the shoe” in Arabic.

What good is having a shoe for a beak? Despite looking silly it’s actually a precision instrument. With it these birds can hunt lungfish, water snakes, frogs, and even young crocodiles. Their favorite method is to stand motionless in pools of low-oxygen water where fish have to come to the surface to breath. When they see movement they pounce, throwing their wings back at the same time so that their huge heads don’t overbalance their thin legs. That comical beak, seen in action, suddenly becomes deadly capable of decapitating prey with a single bite.

An adult shoebill is around five feet tall, not much different in stature from many of their dinosaur forbearers.  A bird that big needs a fair amount of food, probably one reason that they are so intensely solitary. Even a mated pair won’t feed close together, opting instead to keep their vigils at opposite ends of their resident marsh or bog. Nests, too, often have only one egg. The babies are slow to mature, requiring two and a half months just to learn to stand. They don’t seek a mate of their own for about four years, and may live to almost 40 in captivity. 

It’s probably inevitable that disagreement would arise over exactly what kind of bird these oddballs are. They are called storks, but show strong similarities to herons, hamerkops, even pelicans. It’s tempting to think that this is because they are in some sense “primitive”, closer to the rootstock of these different groups. In fact, the opposite is probably true. They are so highly specialized for their particular niche that they have developed a whole suite of adaptations that happen to echo those of other birds. 

Sadly, despite the fact that their range stretches all the way from Ethiopia to Zambia, shoebills are in trouble. Their habitat is horribly fragmented by agriculture and drought while hunting pressure is severe. 

Only about 6,000 remain in the world, making them good candidates for Appendix I of CITES (the most critical designation possible in the Convention for International Trade of Endangered Species). Such a listing would give them a lot more protection and help ensure that we have these modern day dinosaurs around for years to come. 

Animal Mundi: A Very Big Bug by TheFrogBag

A Very BIG Bug

written by Corinna of TheFrogBag

What do you consider a big insect? Half an inch long? An inch? House centipedes can get even bigger, a fact that makes them unwelcome guests in many people’s homes. But there are also folks like the woman who taught my first entomology class. She claimed that house centipedes “are just like little pets that you didn’t have to feed or walk.” She would have loved living in Australia, where at least one insect grows to over eight inches in length.

The goliath stick insect (Eurycnema goliath) is a member of the Phasmatidae family, and despite its large size it’s harmless. It is equipped with neither a venomous bite nor a stinger, although it does have large hooks on its back legs that could maybe leave a scratch. A more likely scenario is that it would simply leave the entire leg behind and escape without it, a fact that definitely makes the goliath the loser in that contest. 

Although relatively common around the city of Brisbane, even most Australians will never see a goliath. That’s because, despite their robust body size, they are masters of camouflage. Completely herbivorous, they spend almost all of their time hanging motionless on shrubs and trees. Their size is actually a benefit in this case since they tend to look just like a twig. The common name of “walking stick” suits them to a T. 

Other adaptations to this sedate lifestyle involve a unique swaying motion while moving (like a twig in the breeze) and the ability to fling their droppings far from the plant they’re resting on. Such a large animal processes a lot of leaves, so it would be easy for a predator to simply look for the mess on the ground and then look up. Goliaths foil this by using a long filament attached to their abdomen to hold the dropping as it is produced, and then, with a quick jerk, send it flying more than a meter away. Oddly, they allow their eggs to drop straight down, but this may well be an adaptation too. The eggs look a lot like seeds and are often picked up by ants, which may allow the young to hatch out safely underground, away from prying eyes. 

But what if, after all that patient hiding, a predator still spots a goliath? An insect of that size, neither toxic nor well-armored, is a real prize for a hungry bird. Well, it turns out that these walking sticks have one more trick up their sleeves. When surprised they open their wings, suddenly displaying a bright red color and a pair of eyespots on their thorax. The display usually makes the bird pause long enough for the goliath to parachute lower in the canopy or jump away.  

Sadly, here in the United States where I live, we don’t have anything even close in size to the goliath walking stick. We do have house centipedes though, in case you were starting to feel lonely. 

ANiMAL MUNDi: The Spirit Horse by TheFrogBag

The Spirit Horse

written by Corinna of TheFrogBag

logo designed by Eva of CocoNme

Photos courtesy of Arkive.org

Ahh, the romance of the untamed stallion. In a thousand photos he stands tall and triumphant against the setting sun. An image like this is emblematic of the American West, encapsulating our fascination with freedom and the unbowed heart. No wonder it comes as a great shock to many people to learn that modern “wild” American horses are the descendants of domesticated Spanish mustangs, and have only been here since the sixteenth century.  

For a truly untamable equine we have to journey half a world away, to Russia, Poland, and Mongolia. There we find the dun-colored, four-foot high Przewalski’s horse (Equus ferus przewalskii) which has never been broken for riding. Or at least we would have found it if it hadn’t been declared extinct in the wild during the 1960s.

Don’t count the Przewalski’s (pronounced sheh-val-skee) out just yet though. These guys are adapted to harsh climates and are nothing if not fighters. In a rare instance of extinction not being forever, enough of these little horse were successfully reintroduced from zoos and breeding programs that they qualified for reassessment by the World Conservation Union. They found that Przewalski’s were actually making a comeback, and bumped their designation up to “critically endangered”. Not exactly out of the woods but a far cry from “extinct”. Today there are more than 400 roaming Kazakhstan and Mongolia, with a further 1,500 still in captive breeding programs, all of them the descendants of just 14 individuals. How’s that for an unbowed heart? 

Like the more familiar domestic horse, Przewalski’s live in bachelor groups composed of young males, or in harems of several females led by one stallion. Unlike domestic horses, they use their sharp hooves to scratch up hidden ground water, a survival tactic that allows them forage where other horses would soon succumb to dehydration. Even so, it is competition with humans for water that has helped push them to the brink. Other threats include human hunters and habitat degradation, as well as hybridization with domestic horses. 

It’s these hybrids that provide a clue to where the Przewalski’s fits in to the equine family tree. Many experts hold that the Przewalski’s is actually the last living ancestor of today’s common horses, despite the fact that they have 66 chromosomes to our horses’ 64. Hybrids, while fertile, have 65 chromosomes. Further crosses end up with 64 chromosomes, and look nothing like the original wild Przewalski’s. What does this tell us? It would seem that the chromosomal evidence points to the two species being cousins instead of descendant and ancestor, a position bolstered by unique blood types found only in the Przewalski’s. 

Despite humanity’s close relationship with the horse we sometimes fail to realize what a truly unique animal it is. Thousands of years ago there were many different species, but today there are only two. The Mongolian word for Przewalski’s horse is “takhi”, meaning “spirit”. Hopefully, with a little help from their human friends, they will retain both their wild spirit and their corporeal form. 

ANiMAL MUNDi: The River Wolf by TheFrogBag

The River Wolf

written by Corinna of TheFrogBag

logo designed by Eva of CocoNme

Photos courtesy of Arkive.org

Otters are playful, smart, loyal, and clever. What could possibly be better? Well, how about a giant otter?

Like their North American cousin the river otter, giant otters frequent slow-moving rivers and quiet lakes. Unlike the river otter, they can reach lengths of 6 feet and weights of over 70 pounds. That’s still shy of the 100 pounds that sea otters sometimes top out at, but giant otters are less compact and therefore longer.

You’d think that such a large animal might be easy to spot, but by most accounts it’s one of the rarest mammals in the Amazon. Critically endangered throughout its range due to deforestation, poaching, and especially the run-off from gold mines, you’d be more likely to see a shy jaguar than this elusive weasel relative.

Even so, if you find one, chances are good that you’ll find another. That’s because giant otters live in family groups of up to 10 individuals. The monogamous parents are known to hunt cooperatively with their offspring, eating up to 9 pounds of prey each, every day. Usually this means crabs and fish, but occasionally they will catch and consume small caimans and even anacondas. Not to be outdone, large caimans and anacondas will sometimes eat small giant otters too.

Since they are such social animals it is not surprising that they have developed a variety of snorts, whistles, grunts, and clicks to communicate with each other. Individuals seem to recognize one another based on their unique white throat patches, the same way that human researches keep track of them in the wild.

Not content to merely hunt and travel together, family groups share dens during the night too. In the morning they typically emerge together, with the youngsters sticking close to their parents so that they can receive fishing instructions. Far from being born with a knack for hunting, most giant otters catch very little for almost their entire first year and must rely on the adults in their group to show them how it’s done. During this time electric eels and rays are a real threat to the curious young otters.

The Amazon is a wild place, full of odd animals not found anywhere else. The giant otter may not be the strangest, but it is certainly among the most charismatic. Affectionately known as Lobo del Rio (river wolf) or Perro de Agua (water dog) throughout its range, its time may be running out.

Fortunately, organizations like the Frankfurt Zoological Society are stepping up to help these amazing beasts. You can help too, by learning about where the gold in your jewelry comes from. Mining the gold for a single ring can leave behind as much as 20 tons of toxic waste, most of which ends up in the water supply after heavy rains. To learn more go to nodirtygold.org

The otters will thank you !

ANiMAL MUNDi: The Strange Case of the Barreleye Fish

The Strange Case of the Barreleye Fish

written by Corinna of TheFrogBag

logo designed by Eva of CocoNme

First discovered in 1939, this half-foot long deep sea dweller was only known from mangled specimens until just a couple of years ago. Like many animals that live at depth, it’s most fragile features never survive the long trip to the surface and the change in pressure differential between the deck of a boat and their home far below. Perhaps it’s no surprise that we didn’t recognize what a truly bizarre creature the barreleye is until we developed the technology to visit it in its natural habitat.

Just how weird is it? To start with, it has a transparent head. Not just a sort-of-translucent-when-you-shine-light-on-it head, but a truly transparent one. Then there’s the fact that its eyes are inside that head. Take a look at the photo: those big green disks at the top of the fish are the lenses, the dark structures under them the eyes proper (hence the name “barreleye”, of course). And those slightly luminescent structures at the front of the fish, where you might expect the eyes to be? That’s actually a pair of olfactory organs (its “nose”, if you like).

Add it all up and this is one of the most unusual animals ever discovered. The weirdness doesn’t stop there though. The fish spends most of its time with those big green eyes pointed upward, looking for food, but it is capable of swiveling them forward, to watch its meals actually enter its mouth, and backwards to look behind it through its own skull.

Okay, so it’s weird. The question is, why? Why have huge eyes when you live in the pitch black? Why have a transparent head when most of us make do with an opaque head? The answer lies in what it eats, and that fact may be the strangest thing of all. It seems that microstoma lives off of plankton, that ubiquitous microscopic food source famous for powering even animals as big as whales. The tried and true method of making a living from plankton is called filter feeding, literally filtering the tiny organisms out of gallons upon gallons of seawater.

That’s just too normal for the barreleye though. Instead, this fish stalks colonial, jellyfish-like animals called siphonophores and steals their food. Siphonophores themselves catch plankton in huge drifting nets of stinging tentacles, which is presumably why the barreleye keeps its eyes under a transparent dome. When working around dangerous materials it’s always a good idea to use eye protection! In addition, siphonophores glow with bioluminescence, making them easy targets for the huge-eyed micro stoma.

Amazingly, almost nothing was known about the barreleye until the Monterey Bay Aquarium Research Institute visited live specimens deep in their natural habitat in 2004. No one could have guessed how the fish really looked based on the distorted specimens brought to the surface in nets. All of which makes you wonder: if an animal this strange is hiding right off the coast of California, what other secrets might the oceans hold?

ANiMAL MUNDi: A Primate of a Different Color by TheFrogBag

A Primate of a Different Color

written by Corinna of TheFrogBag

logo designed by Eva of CocoNme

photographs courtesy of www.Arkive.org

Mammals have evolved to live all sorts of lifestyles. Some dive deep in the ocean. Some burrow under the ground. Some swing through the trees. Some even fly. But one thing they almost all have in common is the color of their irises. Bat, mouse, pronghorn, or whale, all have brown eyes.

There are some exceptions among domestic animals. Cats’ eyes, for instance, can take on a greenish or yellowish hue. Some even have blue eyes, although this trait is often linked to white fur and deafness and so is sometimes termed a mutation instead of a variation.

Among humans it’s a little bit different. In some parts of northern Europe over 50% of the population have blue eyes. In the United States it’s more like 17%. But worldwide the number drops to only 2%, a minuscule proportion of the entire population. But, surprisingly, there is one type of primate where the proportion is 100%.

Blue-eyed black lemurs are almost as rare as their startling eyes would lead you to believe. Although first described by the British Zoologist Sclater in the 19th century, they were not “discovered” in the wild until the 1980s. Today, they are found only in one very small patch of forest in northwestern Madagascar, and are critically endangered.

The fact that they are so rare in the wild and live in such an inaccessible area means that little is known about their behavior. Like their cousins, the black lemurs, their coloration is “sexually dimorphic”, which means that it’s easy to tell the males from the females. Male blue-eyed lemurs are completely black while females are almost blond. Babies are born a brownish color and only acquire their parents’ coloration as they mature.

Female blue-eyed black lemur

Like other primates, these lemurs are very social. They generally live in groups of fewer than 10 individuals, with the ratio of male to female usually skewing towards the males. Even so, it’s the females who are dominant and constrain access to food and mating.

Although probably never numerous, today there are less than 1,000 blue-eyed black lemurs living in the wild. Even so, this small number has big consequences for their forest home. Their favorite foods are fruits, nectars, and pollens. As they forage throughout the day they spread excess pollen grains to widely separated plants and distribute seeds far from the parent trees as they pass through the lemurs’ digestive tracts. In this way they contribute to the richness of their ecosystem and create a more robust forest.

Conversely, when the forest is destroyed by “slash and burn” farming, the lemurs are forced to eat human crops instead. Unfortunately this brings them into direct conflict with humans and leads many of them to be killed as “agricultural pests”.

Male & Female Blue-eyed Black Lemurs Showing Sexual Dimorphism

Thankfully, lemurs are finally getting some help. There are now breeding populations at several facilities around the world and more attention is being paid to preserving what’s left of Madagascar’s wild lands. Hopefully, as new protections are instituted and more are bred at institutes such as the Duke Lemur Center, there’s still a chance to pull these unusual prosimians back from the brink of extinction.