Wednesday, February 26, 2014

Braiiiiiiins

For reasons beyond my geeky comprehension, zombies are kind of the thing right now. There's The Walking Dead, Zombieland, World War Z, I am Legend, and my personal favorite, Plants vs. Zombies.
"Get ready to soil your plants"
Seriously. Addicting. Game.

I may not understand the fascination with zombies, but at least it's better than emo vampires. No matter what form you see a zombie in, from cartoonish to gory, they all want the same thing: your brain. In the natural world, there exist real instances of organisms that target the brains of other living things, turning them into mindless minions to do their bidding. So get out your crossbows and wall-nuts and prepare for some true biological warfare.

Toxoplasmosis: Fear No Death
Toxoplasmosis is a protozoan parasite that infects most species of birds and mammals, including humans. In humans, Toxoplasmosis affects the brain by causing schizophrenia and behavioral changes. However in mice, the changes are even more creepy. Mice infected with Toxoplasmosis lose their fear of cats. What's more, they actually become attracted to the smell of cat urine. Despite the variety of hosts for Toxoplasmosis, it can only sexually reproduce in the guts of cats. By changing the behavior of mice to make them attracted to cats, Toxoplasmosis is essentially guaranteeing a front-door delivery to the stomach of a cat where it can successfully reproduce. Even worse, the affects on a mouse's brain appear to possibly be permanent, even if a mouse is cured of the infection.

Euphalorchis californiensis: No "Safety Dance" Here
Euhaplorchis californiensis (let's call it EP for short, shall we?) is not a protozoan like Toxoplasmosis, but rather a worm. A worm with an agenda. This worm must pass through three hosts in order to complete its life cycle. In the warm refuge of a bird's gut, the worm produces its eggs, which are passed out in the droppings of the bird. Those that are lucky enough to land in water are gobbled up by unsuspecting horn snails. Now inside the horn snail, the eggs hatch
This EP larva just wants to hug your brain
(if you are a killifish that is).
into young larva, which decide to take up residence for a while, rendering the snail sterile in the meantime. Eventually the larva figures it should grow up and make something of its life, and leaves its gastropod home. The larva finds its next home: a California killifish. It enters in through the fish's gills and makes its way up to the brain, where it forms a cyst and directs the fish to swim close to the water's surface, wiggling, convulsing, and jerking in order to attract the attention of a
hungry shorebird. California killifish infected by EP are up to 30 times more likely to be eaten than healthy fish. Once inside the gut of the bird, the worm larva finally matures and lays its eggs, and the life cycle is complete.

Lancet Liver Fluke: Werewolf-Zombie Ants
The lancet liver fluke's story is similar to that of fellow worm EP; there are three hosts, one of which is a snail, and another host must be eaten in order to complete the cycle. The eggs of the lancet liver fluke come from the dung of a cow or sheep, which are consumed by a land snail. Eggs hatch in snail, hang out for a while, and are excreted (told you it was familiar). This time the next host is an ant, that becomes infected when making a meal out of snail slime. However the ant doesn't just go and find its way to a cow and do some sort of shimmy to get eaten. Instead, in a cool of the night, the ant in its zombie-like state makes its way to the top of a blade of grass, clamps on with its jaw...and waits. After all, cows eat grass, not ants. 
Photo courtesy of http://bugtracks.wordpress.com/2011/07/17/mind-control/

But there is an interesting, werewolf-like twist to this tale. If the ant is not eaten immediately, it returns to life as usual with the rest of its uninfected colony come morning. It only lives its double life as cow bait at night. Once the fateful night comes, the lancet liver fluke can complete its life cycle in the belly of the cow or sheep.

Human zombies have a pretty sweet deal compared to the real versions you find in nature. With humans, you become a zombie, then you live out the rest of your zombie life munching on the brains of the slow, stupid, and unarmed...well, until someone hacks your head off with a machete anyway. For the victims of parasites, however, their zombie-like form is a mere transitional state to a gruesome death beyond their control. No brain munching, no scaring teenagers making out in cars, no dancing with Michael Jackson. If reading about these parasites has taught me one thing about surviving the zombie apocalypse, I think it's this: look out for snails.




Wednesday, February 19, 2014

Oh, possum!

Little Henry with Patti, Briar Bush's
business manager
Back in October 2013 at the nature center where I work, we acquired a young opossum from a wildlife rehabilitator to use in our educational programs. Henry, as we named him, was found in his mother's pouch along with his seven siblings when she was hit by a car. Although the mother did not survive, all of the babies did. Two of the siblings, however, had an infection commonly called "crispy ear." Crispy ear is a bacterial necrosis that causes the infected areas to fall off, typically affecting the ears, toes, and tail. Henry's sibling was able to be treated and released along with the six other brothers and sisters, but poor Henry lost all but one of his toes at the knuckle and the tip of his tail before his infection cleared. An opossum that cannot climb to escape predators is doomed to death, and so Henry was deemed non-releasable and came to live at Briar Bush. In the four months that I have been using Henry in programs, I have come across many "myth-conceptions" about opossums that I thought I would take the opportunity to clear up today. So let's get right to it!

Their full name is Virginia opossum
Though many of us call them "possums," the full name is opossum. Opossums belong to the largest family of marsupials (mammals with pouches) in the world, Didelphidae, of which there are 95 species. The Virginia opossum is the only marsupial found in all of North America, so consider yourself fortunate if you see one! Our local opossum is also one of the most variable-sized mammals in existence: males can range from 1.7 to 14 pounds and females from 11 ounces to 8.2 pounds when fully grown. 

Opossums can be cute...really!
Not only can opossums be cute, but they can be ridiculously cute. Allow me to demonstrate here...
Henry says "HI!"

and here...
As you can tell, Henry is quite photogenic...
when I can actually get him to stop moving for one picosecond.

And just to prove it's not just the babies that can be cute, here...
He's smiling because he's warming your heart.

Opossums only play tough guys on TV (and in your yard)
When most people come to me with stories about their opossum encounters, it usually involves this kind of depiction:
...which is understandably terrifying.

Opossums do have the most teeth out of any land mammal in North America, 50 in all (we have 32 by comparison), which they will not hesitate to bear when startled. Even Henry gapes when I wake him up suddenly or spook him when he has his head under some leaves, looking for a tasty treat of dead worms. But opossums are all bluff; they are undeserving of their nasty and aggressive reputations. Opossums are also amazingly resistant to rabies, another myth that has landed this species into a lot of trouble when they are killed out of suspicions of being rabid. In fact when push comes to shove, opossums resort to playing dead rather than going on the offensive, which brings me to my next myth...

Opossums can't snap out of "playing possum"
In the movie Over the Hedge, there is a scene in which Ozzie the opossum plays dead in order to fool the humans. Once he discovers that an exterminator has some more invasive plans in mind, Ozzie immediately recovers and scampers to safety. In reality, not only can opossums not choose when to play dead (it is an involuntary response to extreme fear) but their bodies go into such a state of
shock that it can take up to four hours for them to recover. They do put on quite the show, however; mouth open, drooling, stiff-bodied, they even produce a foul-smelling liquid from their anus that makes them smell like a rotting carcass. There are only two problems with this clever defense. First, playing 'possum in response to a car is highly ineffective and does result in a number of opossum deaths. Also, if a predator comes along that doesn't mind eating dead animals, say a bald eagle, I can't imagine the opossum will fare well here either.



Opossums can do lots of things with their tails, but hanging is not one of them
Opossums' tails are perhaps their most distinguishing feature, and the reason that many people shudder at the thought of opossums and their rat-like appearances. But an opossum's tail is an incredible tool, helping them to balance when walking on narrow branches, acting as a fifth leg when reaching for a distant object in the trees, and even carrying plant material to make nests with. However, opossums are not capable of hanging upside down from their tails. When you see a photo like this on the internet...
the featured opossums are not hanging by choice, but rather because they are attempting to save themselves from a nasty fall (or my guess is that it was staged to result in a "cute" photo opportunity) and only have a short amount of time to recover before the strength in their tails give out.

Opossums are incredible, amazing, misunderstood animals
Opossums are called ugly, nasty, and vicious, but I hope that you have now seen a different side to these marvelous marsupials. Even if you still shudder at the sight of an opossum, you can still secretly think they're pretty cool in their own right and respect their role as a scavenger and clean up crew in the animal kingdom. It's ok, I won't tell. And Henry won't either...he's too busy looking for dead worms to eat.




Wednesday, February 12, 2014

Let's Get it On

Today's post is not safe for the kiddies. Kids, go work on your Valentines for school while Mom and Dad read stories that remind them about how you came to be and maybe want to work on giving you a brother or sister.

In case you were not aware from the bombardment of Hallmark, chocolate, and jewelry-related advertisements going on for the past few weeks, Valentine's Day is this Friday. No matter whether February 14 makes you wear pink, watch romantic movies and shoot cartoon hearts out of your eyes or if it makes you want to shoot things into your eyes, Valentine's Day is a great excuse to talk about sex in the animal kingdom. No matter how adventurous and kinky you may think your sex life is (or want it to be), some of these stories from the animal kingdom make humans look downright boring.

Alright guys, let's get this out of the way right now. The average human penis is 6". And no, by some amazing coincidence every man reading this blog doesn't just happen to be bigger. Well except for maybe you. Well hello there... The following animals have a penis bigger than yours:
Banana Slug
9 inches


Pig
15 inches

This Argentine Lake Duck
16 inches
(the average for the species is 7.8 inches, so still bigger than a human's)

Giraffe
3 feet

African Elephant
5 feet...and it's prehensile
(no, that elephant does not have one leg smaller than the other)

Right Whale
10 feet

But hey, at least your penis is still bigger than a gorilla's:
2 inches

But the biggest penis in the animal kingdom in relation to body size belongs to the humble barnacle. Its penis is over 8 times its own body length! If the human male were that well-endowed, his member would be longer than a school bus.

Seed beetle: Sex as the fountain of youth
Hugh Hefner was a seed beetle in a former life.
When the male seed beetle mates with the female, he inseminates her with chemicals that either make her die younger or live longer. Sometimes the compounds increase the number of eggs laid by a female, and mated females tend to live longer, but in some cases, the compounds are toxic to the female. However males that tend to reproduce late on in life will inject females with more beneficial compounds, in essence extending her lifespan, than males that tend to reproduce early in life. By doing so, the late-breeding males ensure that females will live longer, and hence be around to bear them more offspring, maximizing the number of times their genes are passed down the generations.

Pigs: A twisted relationship
Boars have a corkscrew penis and sows have a spiraled vagina.  This helps to prevent cross breeding in the wild; it’s like a key in a specific key hole. Pigs also ejaculate huge amounts of semen, over a pint each time, which is enough to nearly fill a wine bottle. (You just think of that when you're having your Valentine's drink. You're welcome.)  The last push of semen is thick like tapioca pudding to seal in the previous ejaculate and ensure that the female is fertilized with his sperm and not a competitor's.  
A human ejaculates 1-2 teaspoons of semen each ejaculation, and a right whale 5 gallons per each ejaculation, by the way.

Brown trout: faking it
When solicited by a less than ideal amorous male, female brown trout fake orgasms to encourage male to ejaculate prematurely, duping him into thinking he has successfully mated and go on his merry way to brag to his friends. The female then leaves to go and find a better male with which to do the real thing.

Tidarren spiders: Dude, drop your penis and RUN!
A male Tidarren spider with his
oh so manly pedipalps.
Male spider sex organs are called pedipalps and look like legs or mouthparts. In Tidarren spiders, each of their two pedipalps make up 10% of their weight. That would be like the average male having 18 pound testicles. Each. Male Tidarren spiders may have big equipment, but they are only 1% the size of the females, who would very much like to make a meal out of these potato chip
A tiny male doing his best not to be eaten
during his booty call.
boys. 
Before mating, males voluntarily twist off one pedipalp (he secures it in silk and then turns in circles while pushing on it with his legs) in order to run faster from the hungry female and out compete males with both pedipalps in tact. Males with just one pedipalp run 44% faster and for 63% longer than those with two. It's thought to be easier for these males to run because they are lighter and it's easier to move when pedipalp is not in the way. You try running with 36 pounds of testicles in your pants.



See guys? Bigger is not always better after all. So no matter how you celebrate Valentine's Day, I'm glad that you took some time out to be a voyeur on my blog. I hope I left you satisfied, because it was certainly good for me.

Wednesday, February 5, 2014

Are you Gonna Eat That?

I'm not a Sports Geek or anything close to it, but even I know there was a large sporting event of the football species last Sunday. In years past, I have used the Super Bowl as an excuse to buy all sorts of my favorite junk foods and consume them in large quantities, because it's the American thing to doWe humans eat all sorts of strange things. One example is a favorite of some Broncos fans: rocky mountain oysters. (If you have no idea what they are, let me put it this way...you can only get them from a bull.) Some people eat unusual things to be daring, others for health reasons, and some just like the taste of unusual foods. There are some strange diets among other animals as well, and the stories behind their dietary choices are just as fascinating as the foods themselves.

Grebe: Eats Feathers
Here's another fact about grebes that I didn't mention last week; grebes eat their own feathers. The adults even feed their own feathers to their young, starting at just a few days old. Why would
they do such a thing? Feathers have no nutritional value and they cannot be easy to swallow. The reason is because of the fish they eat which make up the main part of their diet. A grebe's gizzard and stomach are not very well adapted to crush and digest fish bones. It is thought that by swallowing large amounts of feathers, the feathers not only pad the stomach from the pointy fish bones, but may also slow digestion, giving the stomach more time to digest the bones before they pass into the intestines. 


Vampire Squid: Eats Dead Stuff, Plankton, and Poop
Let me answer your first question. The vampire squid was not named for its dining habits, but rather for its resemblance to Dracula: it has skin that can appear black, eyes that can appear red, and a "cape" of skin between its arms. And what is unusual about this squid's diet is that it is the only cephalopod (the group that includes squid, octopuses, cuddlefish, and nautiloids) that is not a predator. The vampire squid lives in waters too deprived of oxygen for its predator relatives and has adapted to the harsh conditions by taking the easy road for finding food. It uses two filaments, up to 40" long and equipped with sensory cells and stiff hairs, to catch what is known as "marine snow" as it floats through the water. Marine snow is essentially the garbage of the animals that live in shallower water, containing dead animal parts and excrement, with some plankton thrown in for good measure. When oxygen is at a premium, you need to conserve as much energy as possible, and the vampire squid has found a way to do just that. Why waste all that energy hunting food as a predator when you can wait with open arms (err, filaments) for food to come to you?

Vampire Moth: Eats Blood
Now here is an animal that lives up to its name. In 2008, scientists discovered a new species of moth in Siberia that feeds on blood. It appears to be a close relative of moths that feed on fruit, and so scientists are now trying to discover why the divergence to a new food source. At the time of its discovery, only males of this moth have been found to feed on blood, so it is suspected that the blood is used as a gift to females to win over mates. If you want to see some truly cringe-worthy footage of vampire moths drilling their proboscises into willing victims, then click the video below.
I think I need to go watch some cat videos now to get that image out of my head.

Cave Cricket: Eats its Own Legs
Like the vampire squid, the cave cricket lives in a harsh environment. Living your whole life in a deep, dark hole, one doesn't come across a food source on a regular basis. To avoid starvation, cave crickets will chew off their own large hind legs as a kind of cannibalistic renaissance fair drumstick. It's a sacrifice that can only be made twice, as the consumed leg does not grow back. Some cave crickets and their relatives, camel crickets, can be found in basements, including my own. Here too, food may not come that easily (unless they want to eat lint, 'cause that's about all I have to offer down there) so even urban crickets may resort to eating their own limbs.
Looks like this guy got hungry.

We may think the diets of grebes, vampire squid, vampire moths, and cave crickets are unusual and a bit unsavory, but then again they may wonder why we eat bull testicles. I think I'll stick with my nachos, pizza, and popcorn, thank you very much.