Monday, April 30, 2012

Scorpions Can Survive Famine, Freezing, Floods, and Heat

Photo Credit: Anders Olsson (via Wikimedia Commons)
We always hear that cockroaches can survive everything, even nuclear war. It turns out that scorpions can survive quite a few less than ideal environments as well. You can find them on every continent except Antarctica, and while they prefer temperatures between 68 and 99 degrees Fahrenheit (20 to 37 Celsius), they can handle a wider range. Many species do fine in extreme heat (up to 122 degrees Fahrenheit) - probably no big surprise there, since so many scorpions live in deserts. Remember that deserts can get quite cold at night, and most scorpions can also handle that with no problem. In lab experiments in the 1980s, scorpions were frozen and thawed, and most survived. Some species can even survive being underwater for two days.

If the ability to handle those environments wasn't enough, scorpions can go up to a year without eating. They do this by actually slowing down their metabolisms, much like hibernating animals do. There is a difference, however. A scorpion can quickly come out of the depressed metabolic state if they need to, while a hibernating mammal needs time.

It's believed that most scorpions only eat 5-50 times per year under normal circumstances. They simply don't need food more often, because their bodies use up most of the nutrients and they produce very little waste. They usually eat insects, but some species will occasionally eat small mammals or reptiles. Scorpions also eat each other! When they do get a chance to eat, they'll eat as much as possible - up to a third of their body weight - thanks to their food storage organ.

Sunday, April 29, 2012

A Horse Never Forgets

Photographer: Nick Stenning (via Wikimedia Commons)
The saying may be "an elephant never forgets," but recent studies have shown that perhaps horses should have that distinction. They remember humans, experiences and even words for several months or years.

In a recent study led by Carol Sankey of the University of Rennes, 23 horses were put through a training program consisting of 41 steps. The horses showed affection to the experimenters and learned better when food rewards were involved. When there was no such positive reinforcement, the horses were more likely to bite or kick. Once they finished the program, the horses and humans didn't see each other for eight months. When they were reunited, the horses stayed close to the people who rewarded them during training. The researchers also said the horses can form lifelong social relationships, can learn human words, and can remember how to solve problems for at least ten years.

The downside to the horse's long memory is that they remember the bad as well as the good. Horses have an easier time remembering things if there's an emotional component, positive or negative. If you do anything to scare your horse, even unintentionally, he will commit that to memory. When it comes to the fight or flight response, horses will always choose flight. This, in combination with the bad memory, might make it difficult to regain his trust. It's doable, it just takes work and lots of patience. Always show him what's in your hands as you approach him, speak to him in a soft voice, and spend as much time with him as possible. Even if horses don't forget, they do forgive.

Saturday, April 28, 2012

Big Cats Cough Up Hairballs

Late yesterday, I stumbled upon the fact that it was National Hairball Awareness Day (yes, seriously). I also stumbled upon the above video from the Big Cat Rescue that shows you a lovely closeup of a lion's hairball (I've personally witnessed a bobcat coughing up a hairball, but not a lion).

Big cats can get hairballs just like our pet cats do, because they groom themselves with their tongues, also just like pet cats do. As almost any cat owner knows, hairballs are formed when the animal swallows dead hair. Some of the hair passes through, but some collects in the stomach, making a hairball. The technical name for a hairball is trichobezoar (a bezoar is an undigestible mass in the gastrointestinal system, and tricho refers to hair). Usually, your cat can cough or poop it out, but hairballs occasionally cause obstructions that require a visit to the veterinarian, and sometimes even surgery. The best thing to do is brush your cat frequently to try to prevent them, and/or feed hairball control food or treats. Of course, this method of prevention doesn't work so well for lions and tigers. In fact, a lion from a safari park in the U.K. had emergency surgery for a hairball a few years back.

Nowadays, we think of hairballs as gross, and cleaning them up is one of the least pleasant pet care tasks. However, not everybody sees them in such a negative light. The word "bezoar" is Persian for "protection from poison" and according to Popsci, ground up hairballs were once used as a sort of cure-all. Today, you can still buy a lion hairball souvenir if you travel to Africa! 

Friday, April 27, 2012

A Tree is Home to Many Animals

Olea europaea subsp europaeaOliveTree
Photo credit: RNBC (via Wikimedia Commons)
We all know that trees are great. They produce oxygen and provide shelter from the sun. They store water, help control erosion and keep soil healthy. They give us flowers, fruit, wood, paper and sap. They also give many animals a place to live.

Birds are probably the first animals that come to mind when we think of tree-dwelling animals (not all birds live in trees, of course, but many do). However, they are far from alone. A tree in your backyard might be a full-time or part-time home to squirrels, opossums, bats, tree frogs, tree snakes, caterpillars, ants, spiders, praying mantises, snails and beetles in addition to birds.

If you head out to other parts of the world and look to the trees, you'll find more thousands of arboreal creatures. As well as the additional species of birds, squirrels, and so on, you might also come across geckos, lizards, lemurs, spider monkeys, orangutans, chimpanzees, tree kangaroos, koalas, tarsiers and sloths. We can't forget cats such as margays, leopards, jaguars and oncillas

Because so many animals live in trees, if you plan to get your tree taken down for any reason, please check for baby animals first if at all possible. (I volunteer at a wildlife rehabilitation center, and "we found baby squirrels/ baby birds when the tree was cut down" is one of the most common phone calls we get in the spring and early summer). If the tree isn't causing damage to your home and you can wait until fall to take it down, please do so.  

Happy Arbor Day!

Thursday, April 26, 2012

Some Sailors Used to Mistake Manatees For Mermaids

Photographer: Ltshears (via Wikimedia Commons)
Legends about mermaids have been around for thousands of years. Many people used to believe these mythical beauties were real (when you think of sailors stuck out at sea for large amounts of time, it's understandable), and some people claimed to have seen them. Even Christopher Columbus said he saw three of them in 1943, and commented that they were "not half as beautiful as they are painted." Now, it's generally accepted that these sailors probably saw manatees, or their cousins dugongs or Steller's sea cows (now extinct).

So, how in the world did people mistake this 12-foot, 1,200 pound marine mammal for a creature that's half woman and half fish? For the most part, manatees remain underwater, and the sailors would usually only see a back and tail with no dorsal fin, which is how mermaids were often depicted. If a manatee head did surface so that a sailor could see the vaguely human-like eyes and face in the right light, it would add to the illusion. Female manatees also have two breasts, one under each armpit (in fact, the word "manatee" comes from the Carib word "manati," which means "with breasts"). One should also keep in mind that these sailors were malnourished, trapped in the poor conditions of the ship, and starving for female contact. They simply weren't thinking straight.

The manatee-mermaid association has made it into the scientific classification of these animals. They belong to the order Sirenia, which is named after the Sirens of Greek mythology (even though the Sirens were originally part woman and part bird, they later became associated with mermaids).

Wednesday, April 25, 2012

Birds Can See More Colors Than We Can

Avian vision is pretty amazing. Birds that have eyes on the sides of their heads (such as parrots and songbirds) have a huge field of view. Some, such as the ringnecked dove, can even see almost all the way around their heads. Raptors, with both eyes facing forward like ours, have superior depth perception. Most birds can see rapid movement as well as extremely slow movement - for example, they can detect the apparent motion of the sun as it moves across the sky. There are even studies that show some birds can see magnetic fields! One of the coolest things about bird eyes is that they can see colors we humans cannot.

You may recall from biology class that eyes have light receptor cells called rods and cones. Rods are more sensitive to light in general, and are important when it comes to night vision. Cones don't work well in low light, but are what allow us to see color, detail, and rapid changes. There are different kinds of cones that respond to different wavelengths of light. As you might remember from physics class, red is at the "long wavelength" end of the spectrum, violet is at the "short wavelength" end, and green is in the middle. Humans are trichromatic, which means we have three types of cones - one that responds most to red, one that responds most to green, and one that responds most to blue and violet. Birds are tetrachromatic. They have a fourth type of cone cell that responds to ultraviolet light, which means they can see it. They can probably also see differences between colors that appear identical to us. This is an advantage in finding a mate and in foraging for food.

There's a lot more to an actual "bird's eye view" than seeing something from high in the sky!

Monday, April 23, 2012

Chameleons Change Color For Reasons Besides Camouflage

BennyTrapp Chamaeleo chamaeleon Samos Griechenland
Photographer: Benny Trapp (via Wikimedia Commons)
We have a name for people who alter their personality and mannerisms to blend in with those around them. We call them "chameleons" or "social chameleons." This name, of course, comes from the belief that almost all of us grew up with -- that chameleons change color to help them hide from predators. As it turns out, this belief is only partially right. Chameleons do change color, but they usually do so for reasons other than camouflage.

According to Dr. John Friel of the Cornell University Museum of Invertebrates, true chameleons (as opposed to the little color-changing anoles that are often referred to as chameleons) change color primarily for communication. They'll turn dark colors or black if scared or angry, and bright colors if they're ready to mate or defend their territory. The light level and weather conditions in their environment also influence the chameleon's color. However, there is one particular species of chameleon, the dwarf chameleon, that changes color for camouflage. These guys can adjust their colors in accordance to the vision of the type of predator!

How do chameleons change color, anyway? Just below their transparent outer layer of skin, they have layers of pigmented cells called chromatophores. The upper layer cells (xanthophores and erythophores) have yellow or red pigment. The middle layer cells (iridophores and guanohores) have guanine, which is blue or white. Below those is a layer of cells with melanin, which can create dark colors. The chameleon's brain sends signals to the cells, causing them to shrink or expand. The colors can even mix like paint.

Sunday, April 22, 2012

There Are Still Millions of Undiscovered Species on This Planet

Animal diversity October 2007
Image courtesy Wikimedia Commons
We all know that life is everywhere on this planet - from our own backyards to the tropical rainforests, and from the deserts to the north and south poles. Just go for a short hike through your local state or city park and you might encounter hundreds of species (mostly bugs, of course). Considering how many animals we already know about, it might seem hard to imagine that there are probably millions of critters out there yet to be discovered.

Currently, scientists have identified approximately 1.37 million species in the animal kingdom. 1.1 million of these are insects and arachnids. Over 200,000 are mollusks, crustaceans, corals, worms and other invertebrates. Only 62,305 are vertebrates, half of which are fish. There are roughly 15,500 species of reptiles and amphibians, almost 10,000 species of birds, and a piddly 5,488 mammals

However, we know there are more. Just last year, researchers from the California Academy of Sciences went on a 42-day expedition to Luzon Island in the Philippines and discovered hundreds of new species, including  several sea slugs, fishes, insects, spiders, corals and four new sharks. One of the new sharks is even "inflatable" - it can puff itself up to scare off predators.

Scientists believe there are millions of other unknown species out there. There are so many habitats that are difficult for us humans to access, such as the deep sea and deep underground, where untold numbers of creatures might live. And of course, we can't forget the tiny organisms that are tough to find simply due to their size. Trying to figure out an estimate of the total number of animal species on the planet is almost as challenging as trying to estimate the total number of stars in the universe. Current guesses range between 3 and 30 million. In other words... we will probably never know all the critters who share this planet with us!

I hope everybody had a great Earth Day!

Saturday, April 21, 2012

Giant Jellyfish Are Invading Japan

Nearly everybody who has been to the ocean or to an aquarium is familiar with jellyfish, and of course, quite a few people have gotten to know jellyfish a bit too well when they were unfortunate enough to come into contact with stinging tentacles. There are many different jellyfish species in the world - at least 350, but possibly over 2000. Jellyfish range in size from about a millimeter to 2 meters in diameter. The Nomura's jellyfish is among the largest, weighing in at around 450 pounds (just over 200 kilograms). These guys have been taking over the seas of Japan in recent years.

This animal normally lives between China and Japan, migrating from the Yangtze River to the Yellow Sea. In summer when the water is warmer, they move to the coasts of Japan and Korea. Even with their huge size, a few of these jellies isn't much of a concern. However, their populations have been exploding since 2002, and they are now wreaking havoc on the Japanese fishing industry. They weigh down and damage fishing nets, and their toxins made fish inedible. In 2009, a fishing trawler was sunk when the crew tried to haul in a net that was full of Nomura's jellyfish.

Nobody is one-hundred percent sure what is causing the invasion. Some scientists believe it's because the water temperatures in the area have increased by 1.89 degrees Fahrenheit, which makes for better jellyfish breeding conditions. Overfishing is likely another factor. Reduced numbers of fish means less competition for the jellyfish, and fishing nets kill off large numbers of sea turtles (a predator of jellyfish).

Friday, April 20, 2012

A Cat's Purr Does Not Always Mean Contentment

Just as a wagging tail does not always indicate a happy dog, purring is not always a sign of a contented cat. Cats do purr when contented, but they also purr when they're not feeling well or when they're injured. They also often purr when they're stressed out at the vet's office. I used to have a kitty (see above pic) who purred constantly while the vet examined him, making it impossible to hear a heartbeat, and I know he wasn't a happy cat during that time!

Science is only now starting to figure out how cats do it (it seems that the brain sends signals to the laryngeal and diaphramatic muscles, causing them to vibrate), but the why is still a bit of a mystery. Some researchers speculate that the purr may have originated as a method of communication - for the mother cat and kittens to tell each other that "all is well." Many cats have figured out how to use purring as a way to communicate with their humans, and they'll often add a meow to the purr to get their way quicker. Another theory says that cats purr to help themselves relax, which would explain why they often purr when hurt or stressed.

According to WebMD Healthy Pets, some scientists believe a cat's purr can also help physical healing. A specialist in bioacoustics by the name of Elizabeth von Muggenthaler was one of the first to suggest this (you may recognize her name if you've read about the paralyzing power of the tiger's roar). The theory says that the frequency of a cat's purr (usually around 25 Hertz) increases bone density and promotes wound healing.

Thursday, April 19, 2012

A Wagging Tail Is Not Always a Sign of a Happy Dog

Alaskan Malamute
© SCMW (via Wikimedia Commons)
Conventional wisdom says that a dog wags his tail when he's happy. However, many dog owners and people who have worked with dogs know that's not always the case. While dogs do wag their tails when they're happy, wags are sometimes accompanied by snarls, growls and even bites - definitely not signs of happiness!

Animal behaviorists and researchers have many theories about what tail wagging means, and they all agree that it's a method of communication. After all, dogs don't wag their tails when they are alone. However, what is the dog trying to say?

Some people say dogs wag their tails to show they are excited, which can be a good thing or a bad thing. Due to the fact that dogs usually wag their tails to greet their "masters," some think tail wagging is a sign of submission. However, studies of wolves shoot a hole in this theory - wolf puppies wag their tails when they see their mother, but the mother wags her tail as well.

Recent studies have shown that the tail wag is more complex than it appears. Animal Planet's dog behavior guide says that we need to look at the tail position, and the direction and speed of the wag to interpret what our canine friends are trying to say. If the tail is wagging toward the right, the dog is happy. If the wag is toward the left, the dog is scared about something. A tail held low means submission or that the dog is upset or worried about something (for example, your dog knocked over your favorite plant and knows you're going to be angry).

Perfect Puppy Care says that a tail held high with only the tip moving is a sign of dominance. This also allows the alpha dog to spread more of his scent.

Wednesday, April 18, 2012

Snowy Owls Are Active During the Day

Tierpark Cottbus Schnee-Eule 1
© Redrobsche (via Wikimedia Commons)
When we think of animals that are nocturnal (active at night), the owl is usually one of the first that comes to mind. However, the Snowy Owl (Bubo scandiacus) is one of the few species of owl that is mostly diurnal, or active during the day.

This bird prefers living in the tundra habitat of the far north, where there are few to no hours of darkness for part of the year. This means that they have no choice but to hunt in the daylight during this time. Throughout the rest of the year, they are able to hunt at night if necessary. 

Even though snowy owls are fans of "the land of the midnight sun," they are nomadic. In winter when the tundra skies are dark all day long and prey is scarce, the owls will migrate south and spend the season throughout Canada, the northern half of the United States, and northern Eurasia. The bulk of their diet is made up of lemmings and voles, but they'll also eat mice, muskrats, squirrels, moles, hares, rabbits and other small mammals. They have also been known to eat carrion, fish, songbirds, waterfowl and even small owls.

Snowy Owl movie trivia: Many people are familiar with the Snowy Owl due to Hedwig from Harry Potter. Even though Hedwig is supposed to be a female owl, the owls who played her (Gizmo, Ook and Sprout) were male. This is because the male snowy owl is smaller than the female, and therefore easier for young actors to handle.

Monday, April 16, 2012

Some Squirrels Are Over 3 Feet Long

Malabar Giant Squirrel-Dogra
© Rakesh Kumar Dogra (via Wikimedia Commons)
Depending on where you live, you're probably familiar with fox squirrels, red squirrels and grey squirrels. The largest of these, the fox squirrel, is about 20 - 26 inches in length. That's pretty big for a rodent, but a species of squirrel that lives in the forests of India dwarfs the fox squirrel. In fact, the entire length of the fox squirrel is about the length of the Indian Giant Squirrel's tail.

The Indian Giant Squirrel (Ratufa indica) has a 2-foot tail, with a body length of about 14 inches. While a fox squirrel weighs a pound or two, the average Indian Giant Squirrel weighs about two kilograms, or just shy of  four and a half pounds.

The size isn't the only impressive thing about this animal. They are an arboreal species (they live in trees), and  they rarely come down to the ground. They travel by jumping from tree to tree, and can jump as far as 20 feet!

Even though they might sound like scary mutant squirrels from a comic book or video game, these guys are less harmful than your average fox squirrel. They prefer to stay in the upper canopy, far away from people (so they won't invade your attic or destroy your bird feeders), and they eat fruit, insects, flowers, eggs, and will sometimes even snack on tree bark. Birds of prey and leopards are predators of this squirrel, and if the squirrel sees one, he will simply freeze or flatten himself against the tree trunk, presumably in the hopes of not being seen.

Sunday, April 15, 2012

Chimpanzees Build Nests

When we think of animals that build nests, birds are probably the first that come to mind. Maybe bunnies, squirrels, reptiles or wasps. In the conventional sense, nests are built for laying eggs and/or raising young. However, chimpanzees build nests for a completely different reason - they make them for sleeping. They find a spot high in the trees and construct the nest out of branches, leaves, and anything else they find that might be suitable. According to the Jane Goodall Institute, chimps sleep in a different nest every night, and they sometimes even make leaf pillows. The only time they share a nest is when a mother shares with her child.

Researchers have studied chimpanzee sleeping nests for a long time, but never understood why they built them. A few years ago, a biological anthropologist by the name of Fiona Stewart decided to spend a few nights in chimp nests to find out. Sometimes she slept in nests that had previously been made by chimps, and sometimes she built her own using chimp techniques. She also spent a few nights on the ground to compare the experiences.

She discovered that the nests were very sturdy and secure in the trees, so there was very little danger of falling out. She slept better in the nests than she did on the ground because there was less worry over predators and snakes. She also received fewer bug bites - only one per night on average when in a nest, compared to 28 while on the ground. 

Saturday, April 14, 2012

The Manakin Bird Can Moonwalk

Many birds have fascinating courtship rituals. Many will sing to attract and/or bond with a mate. Some preen each other. Some feed each other. In some species, the male will build a nest to show his construction skills to the females. Some like to show off their feathers, chest muscles, or their tail feathers (such as the male peafowl and turkey). Raptors and some shorebirds perform stunning aerial displays. Dancing is another popular courtship behavior among our feathered friends, and one of the most entertaining bird dances is performed by the male Red-capped Manakin.

This bird's range extends from southern Mexico, through much of Central America, and into Colombia and Ecuador. Once the rainy season is over (which runs from October through January), the Red-capped Manakin is ready for love. Males engage in "lekking behavior," which means several gather in one location and compete for the attentions of the females. The male manakins look for a long, straight branch without any leaves that might get in their way, and use it as a display perch for the entire season. This bird has four common displays: flying in a circle, darting around the vegetation surrounding his perch, showing off his yellow thigh feathers, and shuffling backwards along his perch. The steps are so tiny and he does them so quickly that, to the human eye, it looks like the Manakin is doing the Moonwalk. When a female likes what she sees, she'll join her chosen male on the perch.

Could you stop watching the video after one viewing? Neither could I.

Friday, April 13, 2012

Black Cats Are Sometimes Associated With Good Luck

Those of us in North America have all heard the myths - black cats are bad luck, especially if the cat crosses your path. It's believed that these myths came from the days of the witch hunts, when black cats were thought to be associated with the devil and witches. Fortunately for black cats and those who love them, most of us have come out of the Dark Ages and recognize these cats as the cool critters they are. Yes, I know, there are exceptions. Not everybody likes cats, some people have a phobia about them, and black cats tend to have lower adoption rates than their more brightly colored companions. Still, it's no longer socially acceptable (or legal) to hurt them.

Not all myths and folklore associated with black cats casts them in a negative light. In ancient Egypt, the goddess Bast (aka Bastet) was often depicted as a black cat. The Norse goddess Freya was thought to drive a chariot pulled by black cats. In Northern Europe during the 18th and 19th century, sailors often chose black cats as "ship's cats" for good luck, and their wives often kept black cats at home because they believed the cat would help bring the husband back safely. A Scottish myth says that if an unknown black cat shows up on your porch, it means prosperity is coming your way. In Japan, a popular Maneki Neko (lucky beckoning cat) color is black. It's believed that the black cat protects children, and keeps stalkers away from young women. It's also said that a young woman with a black cat as a pet will have many suitors (presumably acceptable suitors rather than stalkers). There's an old folk saying that goes along with this idea - "When the cat of the house is black, the lasses of lovers will have no lack."

Happy Friday the 13th!

Thursday, April 12, 2012

The Red Wolf Is Coming Back From Extinction in the Wild

Canis rufus 2 - Syracuse Zoo
Photographer: Dave Pape (Public Domain, via Wikimedia Commons)
As the title says, the red wolf is slowly bouncing back from extinction in the wild. Not "near extinction," but actual extinction.

The generally shy red wolf was once common in the southeastern United States. Even though this animal tends to avoid humans, humans still felt the need to kill off as many wolves as they could in the early 20th century. Extensive predator control programs with large bounties paid to wolf hunters encouraged this. The wolves also lost habitat as humans cut down forests. By the 1930s, red wolf populations were decimated. According to the Endangered Wolf Center, it's believed that only two populations remained by that point. By 1970, less than 100 animals remained. When the Endangered Species Act became law in 1973, the red wolf was declared endangered. The U.S. Fish and Wildlife Service captured as many remaining wolves as possible, and by 1980, the red wolf no longer existed in the wild.

Of the 17 wolves captured, 14 were used to start a captive breeding program. In 1987, enough pups had been raised to start the restoration efforts, and four male-female pairs were released in the Alligator National Wildlife Refuge in North Carolina. There are currently between 100 and 120 red wolves in the wild, all in North Carolina, and around 200 are still in the captive breeding program.

The red wolf is still critically endangered, and it's clear that there's still a lot of work to do to bring the populations back up to stable levels. Currently, the biggest threat is hybridization. Coyotes extended their range into red wolf territory in the 1990s, and the two species started mixing. Fish & Wildlife is working to keep this under control by sterilizing the coyotes. There are also 40 zoos and nature centers around the country involved in the captive breeding program, so hopefully these animals will exist in the wild at healthy levels once again.

Check with the Fish & Wildlife Service periodically for updates.

Wednesday, April 11, 2012

Pets Are Good for Your Health

Dog Walking at Tringford Reservoir - - 1419270
© Chris Reynolds (via Wikimedia Commons)
We pet lovers have always known that being around our furry, feathered and scaly friends makes us feel better. To the nay-saying non-pet owners out there, research backs us up.

You don't need to run any scientific studies to see one obvious health benefit of pets -- increased exercise. Most dogs love physical activity. Taking your dog for a walk or playing fetch with her in the park helps YOU get some physical activity in as well. Even though most cats aren't amenable to the idea of going for a walk, a few will eventually accept a harness and will enjoy exploring the yard with you. I even once met a lady who would put a harness on her pet parrot and let him ride on her shoulder as she walked around the block. She got exercise, and her bird got some beneficial natural sunlight. Even doing simply daily pet care chores such as feeding the little guys and cleaning up after them forces us to get off our butts and move a little.

Animals seem to have a knack for knowing when we need them, and cuddling with a pet always helps when we're stressed or upset about something. Studies have shown that our bodies actually go through changes when we're with our animals. Our levels of cortisol, a stress hormone, is lowered, and we produce more serotonin, which gives us that feeling of well-being.

Of course, if we feel better mentally and emotionally, we aren't as likely to succumb to the physical effects of stress (tension headaches, backaches, high blood pressure, increased risk of heart attack, lowered immunity, and so on). This all goes along with research that shows pet owners are less likely to die from heart attacks or strokes, have lower blood pressure and cholesterol, have stronger immune systems, and are more likely to recover from catastrophic illness.

If you don't have a pet, you may want to consider adopting one. It'll benefit both of you!

Tuesday, April 10, 2012

Walruses Are Chatterboxes

7 Walross 1999
© Ansgar Walk (via Wikimedia Commons)
You'll never hear a walrus say "goo goo g'joob" like you hear in a certain famous song, but these animals do love to vocalize. In fact, they're some of the biggest chatterboxes among the pinnipeds ("fin-footed" mammals). They use their vocal cords to make sounds both above and below water. Like almost all animals, they use body language for some communication, but they also bark, grunt, whistle and click at each other. If young walruses are scared, they bellow for mom (who recognizes the voice of her son or daughter). When males fight for dominance, they roar, cough and snort. A male walrus can use air sacs in his pharynx to make noises that sound like ringing bells or gongs when he's underwater. He does this during the breeding season when he's trying to attract the lady walruses. The air pouches can also be used as amplifiers, and they help the walrus remain upright in the water when he wants to sing to the ladies who are watching from ice packs.

Male walruses can also make a knocking sound from their foreheads, which is unusual because no air is released when they make the sound. Researchers aren't yet sure how they do it.

The moms teach their young how to communicate, and this is extremely important for the health and well-being of the developing walrus calf. Researchers who have studied walruses in captivity have observed that, without that socialization, babies do not eat or grow properly.

You can hear walrus sounds for yourself at the Western Soundscape Library.

Monday, April 9, 2012

PSA - Watch Out For Turtles on the Road

Blanding's Turtle Laying Eggs
Blanding's turtle (Photographer: Justthefacts60)
Today's fact is more of a public service announcement. It's turtle mating season in many parts of the world, which means female turtles are searching for good spots to lay eggs, and male turtles are looking for girlfriends. If roads are in their path, the turtles go ahead and attempt to cross them. Unfortunately, the armor they wear for protection from predators is no match for a car or truck. Populations of turtles have been declining as motor vehicles have become more plentiful. Some species, such as the Blanding's turtle and Eastern box turtle, are now endangered or threatened in many areas. These turtles take many years to reach breeding age (14 - 20 years for Blanding's turtles, and 7 - 10 years for box turtles), so the loss of just one breeding turtle can be detrimental to the species.

Please be extremely careful if you see a turtle on the road, for your own sake as well as the sake of other motorists and, of course, the sake of the turtle. Unfortunately, many accidents are caused by well-meaning folks who swerve out of the way or stop to help, and some of these good Samaritans are hit by drivers who aren't paying attention. Some communities are putting up fences or building wildlife passages (such as the Lake Jackson Ecopassage in Florida) to help divert turtles from the roads. However, until such things are more common, please keep your eyes open for turtles on the road, and take care. Future generations of turtles will thank you!

Sunday, April 8, 2012

A Mother Cottontail Rabbit Can Have 25 Babies Per Year

Eastern Cottontail rabbit nest 20090524 jhansonxi
 © Jhansonxi (via Wikimedia Commons)
I think I was in second grade when I first heard the phrase, "multiplying like rabbits." I thought, "I didn't know rabbits could do math!" I'm pretty sure my mom had to explain what it meant. Anyway, that phrase exists for a reason. A mother cottontail rabbit has four or five babies per litter, and four or five litters per breeding season. If you do your own multiplication, you'll see that comes up to 16 - 25 new baby bunnies every year. Of course, some of those babies will die before they reach adulthood, but enough survive for the population to grow. This can cause problems for farmers and gardeners if there's aren't enough predators in an area to keep the overall numbers of bunnies at stable levels.

According to the History Channel's website, rabbits are a symbol of fertility and new life due to their breeding habits, which could have led to their association with spring, which led to their association with Easter.

Speaking of baby bunnies, if you stumble across a nest and don't see the mother around, don't assume the babies are orphans. Mother rabbits don't stay with the babies 24/7. In fact, they're absent from the nest most of the day, and only feed the babies in the early morning and in the evening. However, if you are CERTAIN the babies are orphaned (for example, if you witnessed your dog or cat killing the mother), do NOT try to raise them yourself. This is a difficult task for a trained wildlife rehabilitator, and an impossible one for somebody without that training. Wild baby bunnies are the most difficult mammals for humans to raise - they have very specific requirements and they succumb easily to stress and infections. Check with your state's Department of Natural Resources for a list of rehabilitators in your area.

Happy Easter/ Passover/ Spring!

Saturday, April 7, 2012

Some Fish Can Walk on Land

Many have heard of lungfish and mudskippers, and know that these fish can survive on land. The critters look somewhat like salamanders and have pectoral fins that resemble legs, so it's not really that surprising to see them slithering through the mud. However, a few species of fish that look like FISH can also "walk."

The climbing perch (actually not a perch, but gourami) has an organ called a labyrinth, which allows the fish to breathe air from the atmosphere for hours at a time. The labyrinth organ is full of "lamellae," which are maze-like plates of thin bone that are covered with a membrane. Oxygen passes through the membrane,where it's absorbed into the blood and distributed through the body. Good thing for the climbing perch, because they have small gills and live in oxygen-poor water, so they need an alternative way of getting air. It's not the end of the world for them when their water dries up, because, unlike most other fish, they can wander off in search of a new home. As you can see in the video, they move across the surface by pulling themselves along with their pectoral fins and gill covers. They have spines under their gill covers to help in the task, and it's said that these spines can hurt anyone unfortunate enough to be on their receiving end. 

These guys are called "climbing perch" instead of "walking perch" because they supposedly have been seen in trees. However, many are skeptical and suggest that any fish in trees were taken there by birds.

Friday, April 6, 2012

Turkey Vultures Have Super-Sniffers

Vulture12 (2)
© Joshin Yamada (via Wikimedia Commons)
Take a close look at this vulture's nostrils. Notice that you can see clear through to the green grass outside the window! This is because the turkey vulture doesn't have a nasal septum (the wall that separates the nostrils). The turkey vulture shares this quality with the other two North American vulture species -- the California condor and black vulture. The turkey vulture's nostrils are the largest of the three species, making the see-through aspect much more noticeable. It's easy for the bird to keep these big open nostrils clean, which is important when you often have to stick your head inside carcasses to eat. One of the last things a turkey vulture needs is a sinus infection brought on by bits of partially rotten meat getting stuck inside his "nose." The perforated nostrils also allow more air to pass through, and with that air, come the molecules that make smells.

There's more to the turkey vulture's amazing sense of smell than just large nostrils. Most of our feathered friends have larger optic lobes in their brains, which process vision, and smaller olfactory bulbs, which process scents. This means that your average bird can't smell very well. Of course, there are exceptions, and the turkey vulture is one of the big exceptions. Put the enlarged olfactory bulb together with the nostrils, and they add up to make one highly developed sense of smell. There's still quite a bit of debate about exactly how powerful that sniffer is. All ornithologists agree that turkey vultures can follow their noses to locate food when the birds are walking on the ground or soaring just above the tree tops. However, some researchers say that it's unlikely that these vultures can smell food from higher soaring altitudes.

Bonus fact: Turkey vultures have been used to locate gas leaks. The compound added to the gas as a warning signal (what makes it stinky) is ethyl mercaptan, which is one of the gasses given off by rotting carrion.

Thursday, April 5, 2012

A Tiger's Roar Can Paralyze

Wild Sumatran tiger
© Arddu (via Wikimedia Commons)
This tiger almost looks like he's trying to paralyze you with his mind. Even though he can't do that, many people have reported being "frozen" or "stopped in their tracks" by a tiger's roar!

Of course, there are people out there who scoff at this. Those who say anybody who believes in the power of the roar is "giving tigers magical powers." However, it's not magic. It's science. It's no secret that sound can have physical and psychological effects. You've experienced this if you've ever winced when nails scraped against a chalkboard or felt pain when you heard a loud, high-pitched sound. It's why sound and music have been used as a form of torture, and how real sonic weapons work. It's why listening to music can be good for your health

Bioacoustics is the study of sound and biology, and how they relate to each other. A researcher in the field by the name of Elizabeth von Muggenthaler has extensively studied sounds tigers make. She and her colleagues discovered that tigers can produce sounds below frequencies of 20 hertz. This is called infrasound, because it's below the human range of hearing (we measly humans can hear frequencies between 20 hertz and 20,000 hertz). Von Muggenthaler believes it's the low frequencies and high volume that can cause paralysis. Infrasound can travel long distances, and tigers use it to communicate as well as to hunt. It can also pass through solid objects, including bones, which is why people such as wildlife researcher and professor Mel Sunquist have reported being able to feel the roar. Infrasound has been shown to produce chills, stress, and even sorrow. Some people even think it could explain reports of ghostly experiences. In any case, infrasound is one more weapon in the tiger's arsenal, and yet another reason these cats are among the world's top predators.

Wednesday, April 4, 2012

Octopus Arms Have Minds of Their Own

Octopus vulgaris.003 - Aquarium Finisterrae
© Drow_male (via Wikimedia Commons)
In recent years, we have learned that the octopus is rather intelligent. These little guys have figured out puzzles and mazes. They can open jars and child-proof pill bottles. Octopus keepers often have to come up with ingenious methods to secure tanks to keep the critters from escaping. There are anecdotes all over the internet about octopuses/octopi* sneaking out of their tanks, crawling to a neighboring tank to snack on the fish and then return to their own tanks. Sometimes an octopus who is bored rather than hungry will also cause mischief -- just ask the staff at the Santa Monica Pier Aquarium. They came in to work one morning to find that an octopus had entertained herself the night before by taking apart the tank's recycling system valve. The place was flooded, and the employees had to work frantically to get everything cleaned up before the day's school groups arrived. If the octopus could talk, she could have said, "Sorry, but my arms have minds of their own," and she wouldn't have been lying. According to an article in Scientific American, only about one-third of an octopus's neurons are in the brain. The rest are found throughout the body, primarily in the legs. The suckers have their own ganglia (bundles of neurons) that allows the octopus to control them individually. They can even pinch with those suckers.

*Though many people use "octopi" as the plural for octopus, others object to this form. They say it comes from the assumption that "octopus" is a Latin word, when it actually comes from Greek (oktapous, meaning "eight-footed"). "Octopodes" would be the Greek plural, but it's rarely used (probably because people would look at you strangely if you did). Merriam-Webster says that either "octopuses" or "octopi" is correct. I personally think "octopuses" sounds... odd. Maybe it's because I can't hear/read/write it without thinking of "Octopussy."

Tuesday, April 3, 2012

Alligator Snapping Turtles are Expert Fishermen

Do you see that pink wiggly thing in the turtle's mouth? It looks just like a worm, doesn't it? Well, it's actually part of the turtle! The alligator snapping turtle has a vermiform (worm-shaped) appendage on the end of his tongue, which means he never has to run to the bait shop or sporting goods store when he wants to catch something to eat. All he has to do is find a comfy spot on the river bottom, open his mouth, and sit as still as possible. The fake worm coupled with the cave-like appearance of the turtle's head is enough to draw curious and hungry fish. Then, as you might imagine, the fish becomes the meal.

This is an example of aggressive mimicry (aka Pekhamian mimicry, named after George and Elizabeth Pekham). Basically, this means a predator appears to be something else -- something harmless -- so that the prey doesn't recognize it as a threat. This way, the predator doesn't have to do any actual hunting. He just waits for the prey to come along. A lure isn't required for an animal to be considered an aggressive mimic - the ability to closely approach prey is enough - but the lure definitely makes things easier for the turtle.

Note: A human going fishing is a different situation. For something to be considered an aggressive mimic, the mimicry cannot be intentional. In other words, the turtle was born to fish. He naturally has all the equipment he needs. A human has to go out and buy rods, reels and bait.

Monday, April 2, 2012

Cats and Dogs Have Unique Nose Prints

Cat Nose Close-up (Source: Own work)

Take a close look at your cat or dog's nose (a magnifying glass would probably be helpful), and you'll see little bumps and ridges. Just like humans have fingerprints, cats and dogs have nose prints. These nose prints are unique to the animal, and can be used for identification. There's a rumor floating around the internet that the Canadian Kennel Club accepts nose prints as proof of a dog's identity and has done so since 1938, but I've been unable to confirm it. Searches on the CKC website for "nose prints" and "nose printing" come up empty, and their page on dog identification only refers to microchips and tattoos. So, I'm personally inclined to believe it's just a rumor (or perhaps they did accept nose prints at one time, but no longer do). Also, there is no central database for nose prints. I've seen references to a company called Dognose ID that supposedly keeps records of dog nose prints, but as of this writing, their website has been disabled.

Whether a valid form of identification or not, nose prints can be fun. You can find artists on Etsy who will make a charm from an impression of your pet's nose (note: I have no connection to Etsy or any of these artists). If the jewelry is above your budget, the website has instructions for obtaining a print of your dog's nose using food coloring (scroll to the bottom of the page). I'd imagine the same technique would work for cats as well, but you might want to don some protective gear first. 

Sunday, April 1, 2012

The Common Cuckoo Has a Strange Diet

Welcome to my brand spanking new Animal Facts blog! My goal is to bring you fun or interesting facts about animals each day, but I hope you'll forgive me if I miss a day here and there.

Anyway, since it's April Fools' Day, I decided to launch this blog than with some information about the bird that likes to make a fool of other birds -- the common cuckoo!

Cuculus canorus vogelartinfo chris romeiks CHR0431
© Vogelartinfo (via Wikimedia Commons)
The Common Cuckoo dines on toxic caterpillars.
The Common Cuckoo (Cuculus canorus) is fairly popular due to the use of its likeness in clocks, its "coo-coo" call, and that cartoon bird who's cuckoo for a certain chocolate flavored cereal. Many people also know them because they are brood parasites -- birds that sneak their eggs into the nests of other birds and leave the host parent(s) to raise the chicks. Another tidbit about the Common Cuckoo has to do with this bird's diet.

Like many birds, cuckoos eat insects, spiders, worms, and caterpillars. However, there are some caterpillars that absorb toxins from the plants they eat, becoming toxic themselves. Most birds have learned to avoid these critters, but not the cuckoo. She doesn't let something as trifling as deadly poison keep her from her tasty meal. She simply bites the caterpillar's head off, and then shakes the body to expel the toxins before swallowing it down. I should also mention that many of these caterpillars are covered with barbed hairs, but that's no problem for the cuckoo either. She periodically sheds her stomach lining, embedded barbed hairs and all, and regurgitates it as a pellet.

Bonus Fact: The Common Cuckoo is native to Europe and Asia. It's North American cousins are the Yellow-Billed Cuckoo, Black-Billed Cuckoo, and the Greater Roadrunner. All three of these species raise their own young, however, the Yellow-billed and Black-billed Cuckoos will occasionally lay eggs in the nests of other birds.