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.

Indoor Cats: It's Only Natural

When I was growing up, I had a cat named...I'm not making this up...Kinky. This is what happens when you let children name a cat. He had kinks in his tail, hence: Kinky. I grew up a cat lover and had Kinky by my side for 14 years. 

Me and my big sister, Jenny, with Kinky in the window (before he put on a few pounds). 

What my sister was up to in this picture, I have no idea, 

but it probably involved corrupting my sweet, innocent, 2-year old mind.

On occasion, we'd let Kinky roam outside, but always accompanied. We were too worried that he'd meet his end either via vehicle or neighborhood dog. I always joked that Kinky posed no threat to wildlife as birds spent more time terrorizing him than he did them. That and the fact that my cat weighed 20 pounds would probably have made him a pretty poor hunter.  

The truth is that cats are in fact superb hunters, relying on thousands of years of instinct to catch their prey. They are some of nature's finest predators, and this includes our own pets. There are three kinds of domestic cats you will encounter outside: "outdoor cats", strays, and feral. "Outdoor cats" are those that are allowed to freely roam outside by their owners, whereas strays are ones that have either run away from their homes or have been abandoned by their owners. Feral cats are those that have never been a pet; they were born in the wild. The issue of outdoor cats is a long-contested and hot button topic. Today, I thought I'd answer what are some of the most common questions and comments that I hear about cats.

Cats are a part of nature, and they have to eat too. Why is it bad that they eat wild animals?

The answer here is that domestic cats (Felis domesticus) are not a part of nature. They have been bred for thousands of years to be a companion to man, to dwell along side of us within our households. A cat is no more a part of nature than a domestic chicken, dog, or hamster.

This is why outdoor cats are such a sensitive topic among biologists--they are not a native and wild species but are having a profound impact on true wild native species. They not only cause a decrease in bird populations (cats are the number one cause of mortality for birds), but threatened and endangered species of other animal groups as well, including sea turtle hatchlings.

I think this is the expression Kinky would have
 had if we made him wear a collar like this.

What if I put a bell on my cat's collar?
Cats are very, very, good hunters, and can learn to sneak along without causing a single bell chime. And because cats with bells on their collars learn to adapt their hunting style, it actually makes them even better and more efficient predators.

"I swear I wasn't going to put this
at the foot of your bed."

If I feed the stray/feral cats, they won't need to hunt. 
This is one of the most common misconceptions about stray and feral cats, and unfortunately it is not true. Even a well fed cat still has its predatory instincts intact and will still hunt. A great example of this is cat owners who find little "gifts" in their house such as birds and lizards. The cats are well cared for and fed, but still catch and kill wildlife.

In addition, feeding stray and feral cats only causes their populations to increase. When an animal has ample resources for survival, its body's response is to breed. By providing more than enough food that the cats need to survive, they breed frequently and populations skyrocket. A female cat can start to breed as early as five months of age, and can have two to three litters a year. I may not have my calculator handy, but I can tell you that is a lot of cats! (But if you really want to see the math, look here)

Cats only pose a risk to the animals that they hunt.
Feral cats have introduced Feline Panleucopaenia (FPL), closely related to the lethal canine parvo, into not just other domestic cats, but wild cat species as well such as bobcats and panthers. Untreated, FPL has a 90% mortality rate. In Florida, the endangered Florida panther population has contracted FPL, further contributing to their decline. 


So what can I do?
If you do see a stray or feral cat in your neighborhood, please do not feed it. Contact a local shelter or cat rescue; they may be able to help you find a home for your feline friend. If you have an outdoor cat, it is possible to convert it to be an indoor cat--be patient and stick with it...you can do it! There are many resources online for helping your cat (and yourself) make the transition from the urban to the indoor jungle while making sure your cat is still enriched mentally. Indoor cats live longer, healthier lives and in turn your backyard wildlife will live longer and healthier lives too!