Wednesday, October 3, 2012

Watch Out for Zombie Bees

Maciej Czy┼╝ewski, CC-BY-SA-3.0,2.5,2.0,1.0, via Wikimedia Commons

"Zombie bees" (aka zombees) are showing up is some parts of the United States. Don't worry, they aren't coming after our brains. The poor critters are infested with a parasite.

Apocephalus borealis, a fly known as the "scuttle fly" or "zombie fly", is the culprit. This insect has been known to infect bumble bees and paper wasps in the past, but now it is also using honey bees as hosts. The adult fly lands on the bee's back and injects the eggs into the abdomen. The eggs hatch, and the maggots eat the bee from the inside while they grow. Once a bee is infected, it will abandon the hive at night and fly around erratically in movements reminiscent of a zombie. This goes on until the bee dies and the maggots crawl out to pupate. 

As of October 3, 2012, the problem is primarily in California, where the bees were first discovered in 2008. However, confirmed cases of infection have also been confirmed in Oregon and Washington State, and as far east as South Dakota. The flies themselves have been found scattered across the United States and Canada, all the way to the east coast.    

The honey bee has been a victim of unexplained die-offs around the world in recent years. Bees are also susceptible to a variety of other parasites, bacteria, fungi, and viruses. The zombie fly is yet another threat to populations of one of our most important pollinators.

You can find updates on the spread of the infection at ZomBee Watch.

Monday, October 1, 2012

Some Pets Can Contract the West Nile Virus

Electron Micrograph of West Nile Virus (CDC Image, via Wikimedia Commons, PD-USGov)
2012 was a record year for the West Nile virus. We already know that this virus is zoonotic, which means it can pass from animals to humans, and from humans to animals. What does this mean for our furry, feathered, and scaly friends?

West Nile Virus in Cats and Dogs
There are two ways a dog or cat could possibly be exposed to this disease. He may be bitten by an infected mosquito, or may decide to snack on an infected prey animal such as a mouse. That being said, dog and cat owners can relax a bit. The West Nile virus doesn't seem to cause much harm to our two most popular pets. In an experiment, cats and dogs were intentionally infected with the virus (yeah, I'm not crazy about that either). The dogs and some of the cats didn't show any symptoms, and the rest of the cats experienced only mild symptoms such as lethargy and a slight fever. (You can read the report here, but I recommend stopping after the abstract if you're a cat and/or dog lover).

Even though WNV probably won't harm the health of your cat or dog, if you notice any suspicious symptoms, contact your veterinarian. He or she can provide supportive care for your pet if necessary.

Reptiles and Amphibians
Studies have been done with iguanas, garter snakes, bullfrogs, and turtles (specifically, red-eared sliders). In one experiment, the iguanas, snakes, and bullfrogs became infected, but none exhibited symptoms. In a different study involving only garter snakes, 4 of 9 snakes died. Young crocodiles and alligators seem to be the most susceptible to WNV - there have been outbreaks of the disease among wild alligators in multiple states. Also, there have been transmission studies that strongly suggest the virus can pass directly from an infected alligator to tankmates. Symptoms to watch out for are "star gazing" and mouth lesions.

There's good news and bad news for horse owners. First, the bad news is that horses are susceptible to the WNV. Most horses that get bitten do not get sick, however, those that do get sick show symptoms of encephalitis such as loss of appetite, depression, weakness, muscle twitching, paralysis, convulsions, or coma. The good news is that vaccines are available for horses. Vaccination is obviously your best protection, but other ways to reduce your horse's risk include: keep your horse inside during peak mosquito times, set up fans in the stable to help keep mosquitoes out, eliminate standing water, and check the property frequently for dead birds. If you do find a dead bird, call your local health department, and of course, never touch a dead wild animal with your bare hands.

Small Mammals (Pocket Pets)
Many small mammals have been experimentally infected with WNV. Mice, rats, and hamsters developed clinical signs (some severe). Guinea pigs and rabbits, however, did not become sick.

West Nile Virus in Pet Birds
Wild birds are the primary hosts of the West Nile virus. Crows, jays, thrushes, chickadees, and raptors are among the most affected. The virus has been reported in approximately 300 species of birds, so as one might guess, pet birds can become infected as well. Fortunately for parrots and their owners, psittacines seem to have at least some resistance. However, there have been a few cases in parrots such as macaws, cockatoos, conures, budgies, and cockatiels, so no bird is 100% safe. Some birds with the virus experience weight loss, weakness, fluffed feathers, or neurological symptoms such as paralysis, lack of coordination, circling, or seizures. Other birds experience no symptoms at all. For some, the only symptom is sudden death.

Officially, there is no vaccine available for birds,* and you should never use insect repellents on or near your bird due to the fact that birds are much more sensitive to chemicals than we humans are. So, how do you protect your birds? If your birds are indoors, they are pretty well protected as long as you keep your doors and windows closed (or screened) to avoid letting mosquitoes into the house. If your birds are in an outdoor aviary, you may wish to consider bringing them inside during peak mosquito times. If that's not possible, you can try using mosquito netting, and of course, make sure there's no standing water nearby.

As always, if you notice any symptoms, contact your veterinarian.

*Some zoos are using the equine WNV vaccine on their outdoor birds, and are experiencing some success with it. However, the vaccine has not been officially approved for birds as of yet.

Saturday, May 19, 2012

Those Scary-looking Anglerfish With the Big Teeth are Female

Public Domain Image (PD-1923) via Wikimedia Commons
This deep sea fish may be familiar due to its appearance in Finding Nemo, as well as its appearance on almost every list of "the world's ugliest animals." However, you're not likely to see one in person. Seeing a male deep sea anglerfish would be even less likely, and if you did see one, you probably wouldn't know it. When it comes to the humpback anglerfish (the kind in the above drawing) and "sea devils," the fishing lure and huge mouth full of teeth belong only to the females.

You may wonder where the males are. Well, you'll usually find them connected to the body of the female. When a male angler becomes sexually mature, his digestive system stops working. His options are then to either die of starvation, or find a female and join with her as a parasite. Neither option is a great one for the poor male. When he finds a female, he bites her, and then his mouth dissolves into her body. Their blood vessels merge, and over time, the male's organs are absorbed until the only things left of him are his gonads. The female can then use them when she wants to spawn, and she can end up with up to six "males" attached to her.

As far as the lure and giant teeth: the female uses her lure like a human angler would - to draw her prey (other fish) close enough for her to snatch with those teeth. The teeth are angled inward to help keep the prey from escaping, and her jaw and body are pliable enough to allow her to eat prey twice her size.

(Apologies for the lack of updates lately. My classes are starting to take up most of my time. I'll post again soon... I promise!)

Thursday, May 17, 2012

The Blue-Footed Booby Has Multipurpose Feet

Sula nebouxii - 06
Photo Credit: Maros (via Wikimedia Commons)
The Blue-Footed Booby is a bird with feet that are made for more than just walking. Like most seabirds, his feet are webbed and work as paddles for swimming and diving. On the downside, the web shape makes the bird clumsy as he walks on land, which is where his funny name came from ("booby" comes from the Spanish word "bobo," which means "stupid" or "clown"). Even so, the male blue-footed booby is quite proud of his feet, and he uses them to help attract a mate.

As one may guess from this bird's name, the feet are often blue in color. However, the color actually ranges from bright green to dull blue. When the male is ready to attract a female, he will perform a courtship dance full of struts and high steps - all moves meant to show off his feet. Studies have shown that females tend to prefer bright green, and that the color is dependent on the amount of carotenoids in the diet. Therefore, it seems the color is an indicator of the booby's nutritional condition (and suitability as a mate). 

The blue-footed booby has one more important use for those feet. These birds do not have brood patches (a bare patch of skin on the bird's belly for sitting on the eggs), so they use their feet to keep the eggs warm. The parents will continue using their feet to keep the babies warm even after hatching, as the chicks are unable to control their own temperatures for about the first month of life. 

Tuesday, May 15, 2012

A Cheetah's Speed Has a Downside

Gepardjagt1 (Acinonyx jubatus)
Photo Credit: Marlene Thyssen (via Wikimedia Commons)
We all know the cheetah is one fast cat. They can go from 0 to 60 miles per hour in a little over 3 seconds, and can reach speeds of 70 miles per hour, making the cheetah the fastest land animal. Watch a cheetah run and you can't help but be impressed. Their stride can be as long as 25 feet, and at top speed, they can make 3 strides per second. Unfortunately, this amazing speed has a downside for the cheetah.

A cheetah is literally built for speed - their bodies are aerodynamic in shape, they have huge hearts for pumping lots of blood, large lungs and nostrils, a flexible spine, and a long tail that can act as a rudder and counterweight to keep the cat steady as he runs and turns. This sounds great for the cheetah, but it turns out that running is practically the only survival skill he has.

The cheetah weighs an average of 125 pounds, which is small for a big cat. When the cheetah runs at top speed (which he can only do in a short burst), the heart pumps so hard and the body becomes so hot that brain damage can occur if the cat doesn't rest before eating. During the rest period, other predators or scavengers can come in and steal the prey, and there's nothing the cheetah can do about it. The cat is exhausted, and due to his aerodynamic shape, he doesn't have the muscle mass or strong jaws and teeth needed to fight back. All he can do is run.

Some people believe the overspecialization is part of why the cheetah is endangered, but most researchers believe the primary issue is the usual human created problem of habitat loss, along with loss of genetic variation. Fortunately, groups such as the Cheetah Conservation Fund are working to make sure this beautiful cat survives. 

Sunday, May 13, 2012

Elephants Make Great Mothers (and Grandmas, Aunts, Sisters and Cousins)

African Bush Elephants
Photo Credit: Gorgo (via Wikimedia Commons)
Yesterday, we talked about how alligators are great moms. On Mother's Day, we'll talk about another great mom from the animal kingdom - the elephant.

Female elephants have a complex social structure which is centered around the raising of offspring. When a young female reaches the age of around thirteen, she'll go into her first estrus. In other words, she'll be "in heat." This phase only lasts a few days, and will be one of the only times an adult male elephant is involved in a herd (males are usually solitary once they come of age). After mating, the female will carry the baby for 20 - 22 months. When the mother goes into labor, the entire herd will surround her and stand guard while she gives birth to a 150 - 220 pound calf. The herd will then greet the newborn, who is born practically blind and with few survival instincts.

Over the next two years, the calf will be dependent on her mother for food. She will survive completely on her mother's milk for the first few months of her life, and will drink about 10 quarts (about 9.5 liters) every day, which is enough for her to gain 30 pounds a week. The calf will start eating on her own at around age two, but mother's milk will still be a part of her diet.

The mother isn't the only one who takes care of the baby. The rest of the herd, which will consist primarily of related females (with some male calves) will aid in protection, teaching survival skills, helping out if the baby falls or gets stuck, and so on. 

If the calf is a female, she will remain with the herd once she becomes an adult (if the herd becomes too large, some of the elder females will break off and start their own herd). If the calf is male, he will head out on his own at around the age of sixteen.

Happy Mother's Day!

Saturday, May 12, 2012

Female Alligators are Great Mothers

Alligator Baby
Photo Credit: William Stamps Howard (via Wikimedia Commons)
When we think of animals that are good parents, reptiles usually don't come to mind. We tend to think that reptiles aren't very maternal - that they lay their eggs and move on with their lives. However, alligator mothers are some of the best moms around! (With babies as cute as the ones in the picture, how can they not be?)

A female alligator will begin breeding when she is between 7 and 12 years old. Males and females come together to mate in spring, and once the deed is done, the female will search for a place to build a nest. She will gather reeds and other plants to create the mound shaped nest, which will be about 3 - 3.5  feet tall and 7 feet wide. Then she'll lay between 20 and 60 eggs and will cover them up. She'll let the heat from the vegetation in the nest keep the eggs warm (being huge and cold-blooded, she doesn't sit on the eggs to warm them with her body like a bird would). 

The mom remains on guard near the nest for a little over two months while the eggs incubate. The babies chirp as they hatch, and when the mom hears the sound, she'll uncover the nest. If any babies are having difficulty hatching, mom will gently roll the egg in her mouth to crack it. Once all babies are out, mom will carry them in her mouth to the water, where they'll gather together in a pod. 

Baby alligators can hunt and swim, but they are too small to defend themselves from predators such as raccoons, snakes, raptors and herons. The mom will use her powerful jaws and huge body to protect as many of her babies as she can, and the family stays together for at least a year (sometimes two).

Friday, May 11, 2012

Dolphins Vocalize Through Their Noses

Bottlenose Dolphin KSC04pd0178
Photo Credit: NASA (Public Domain image, via Wikimedia Commons)
Dolphins always seem to have their mouths open when they chatter and whistle, so it's easy to assume the sounds are coming from their throats. However, unlike most other animals, dolphins do not have vocal cords. For a long time, scientists believed dolphins produced sounds from the blowhole, but now it looks like dolphin sounds come from their nasal cavities! 

Dolphins produce different sounds such as squeaks, moans, trills, grunts, and so on. They're most famous for their whistles, and they even have what we call "signature whistles" that they use to identify each other. These whistle sounds were a mystery to researchers for a long time, because dolphins are able to produce the sounds underwater, and a true whistle is produced by a stream of forced air. There's also the fact that there's compression when a dolphin dives, which should change the frequency of the sound, but the frequency remains the same.

Last year, researcher Peter Madsen and his colleagues at the Institute of Bioscience in Denmark re-examined a study from the 1970s in which scientists had dolphins breathe heliox (a mixture of helium and oxygen) because it should have mimicked the conditions during a dive by causing a change in frequency. However, the whistles were the same, whether the dolphin was breathing heliox or regular air. Madsen's group concluded that dolphins probably make the whistling sounds by vibrating tissues called "phonic lips" that are located in their nasal cavities. Dolphins can quickly change the frequencies of the sounds by changing the tension of the tissue and the airflow. They can whistle and click at the same time because they have two sets of "phonic lips" that can either work independently or together. 

Tuesday, May 8, 2012

The Gentoo Penguin is the Fastest Penguin in the World

Gentoo Penguin Swimming
Photo Credit: Priya Venkatesh (via Wikimedia Commons)
We've all watched penguins swim at zoos and aquariums (or at least on television). Their movements seem effortless as they glide through the water, occasionally diving, and occasionally leaping above the surface for a breath of air. The fastest swimming penguin, the Gentoo Penguin, can reach speeds of 36 kilometers per hour (that's a little over 22 miles an hour for those of us who live in the USA), thanks to their streamlined bodies and strong flippers. 

The Gentoo penguin lives on the islands surrounding Antarctica and the Antarctic Peninsula (and with Mr. Popper of Mr. Popper's Penguins). Even though they're adapted to living in cold climates, they prefer areas without much ice. They mainly eat krill, squid and other crustaceans, but will also eat fish. 

The adult birds hunt all day long and occasionally venture out about 26 kilometers (16 miles). Because of their ability to hold their breath for seven minutes, they can dive up to 200 meters (655 feet) while chasing after something to eat. They are most vulnerable to predators such as seals, sea lions and orcas while out hunting, so they usually remain close to the shore. When they're on land, the adults only need to worry about humans who sometimes hunt them for their skin and oil. Birds of prey will sometimes dine on penguin chicks and eggs.

This species of penguin is doing well on the Antarctic Peninsula, but populations are dropping on the islands. They are now classified as a Near Threatened species on the IUCN Red List of Threatened Species.

(Apologies for the lack of updates the past few days).

Thursday, May 3, 2012

There Are Vulture Restaurants in India, Nepal, and Pakistan

Photo Credit: Petra Karstedt (via Wikimedia Commons)
If you ever take a trip to India, Nepal, or Pakistan, you can visit a "vulture restaurant." No, a vulture restaurant isn't a place where those who enjoy adventurous eating can sample vulture curry. It's a place where the critically endangered White-rumped and Slender-billed vultures can fill up on safe meat.

Twenty years ago, populations of these vultures were doing fine. There were 50,000 nesting pairs of the two types of vultures in Nepal alone. The numbers have since dropped sharply, and now there are only around 500 pairs. Hem Sagar Baral of the Nepalese Ornithological Union said that if things don't improve, both species could be extinct in ten years.

It's believed that the decline is partially due to habitat loss (a reason we see over and over again when animals become endangered), and partially due to a drug called diclofenac that is often used to treat inflammation in cattle. While generally safe for the cattle, this medication is deadly to vultures. If a vulture eats the meat of an animal that had been treated with diclofenac, he can go into kidney failure, which ultimately ends in death. The drug has since been banned and a different anti-inflammatory drug that is safe for vultures (meloxicam) is being produced. However, some people still use diclofenac for their animals.

A few years ago, Bird Conservation Nepal had a great idea - to open up "restaurants" for the vultures! The idea slowly caught on, and now there are a handful of feeding stations and plans for more. So far, the stations have been successful, for many villagers as well as the birds. Authorities pay villagers for their dead diclofenac-free cattle, and the restaurants draw paying tourists. As far as the vultures, the number of nesting pairs near the Pithauli station has grown from 17 to 46. A captive breeding program has also been started in the Chitwan National Park, so it looks like there's a good chance for a comeback!

Wednesday, May 2, 2012

The Fennec Fox is the Smallest Canid in the World

Fennec Fox
Photo Credit: Yvonne N. (via Wikimedia Commons)
The Fennec Fox one of the cutest animals in the world, and is also the smallest species of canid (the family of mammals that includes dogs, wolves, foxes, jackals, and other dog-like animals). These little guys are even smaller than most of the dogs some celebrities like to carry around in purses. Your average Chihuahua weighs 3 - 6 pounds, and the fennec fox weighs in at 1.5 - 3.5 pounds. The fox's height and length are similar to those of the Chihuahua, but much of their size is taken up by ears and tail. The tail is 7 - 12 inches long, and the ears are about 6 inches each!

Fennec foxes are native to the Sahara desert and other parts of northern Africa. Living in the desert, they need a way to keep cool, and that's what the gigantic ears are for. There are lots of blood vessels near the skin of those ears, which help radiate body heat. Their light colored fur reflects the heat of the sun and protects the fox's skin, and it also keeps them warm during the cold desert nights.

Five more Fennec fox facts: 
- Like many desert animals, they can live for long periods of time without drinking water (they survive from the moisture in their food).
- Their diet consists mainly of insects, but they also eat rodents, lizards, and plant matter.
- They have fuzzy feet to help them walk on the hot sand.
- When temperatures rise above 35 degrees Celsius (95 Fahrenheit), the foxes may start to pant. When panting, their respiratory rate rises from 23 breaths per minute to 690 breaths per minute.
- The "copulation tie" has been known to last two hours and forty-five minutes!

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.