Friday, May 11, 2012

slutamanders


I know, I know. I’m worthless. I apologize for the lack of consistent posts. Or really, the lack of recent posts, period.

These past two weeks have been very busy. I wrapped up my illustration gig in Auburn, moved back to Louisiana, and repacked everything to move to Alaska. (I’m on the flight between Dallas and Seattle as I write this.) Once I get settled into my new surroundings, I promise more consistent (and likely raptor and Alaska-themed) blog entries. Excuses, excuses, I know. You don’t want to hear it. You want to hear some science, don’t you?

Salamanders are a curious bunch. I bet there is a population within a mile of where you live, and you don’t even know it. They’re small and hang out under logs and damp earth. Not the flashiest or most gregarious amphibians, but common and pretty darn cute.

A particular family of terrestrial salamanders- the Plethodontids- are particularly interesting. Their small size allows them to breathe entirely via diffusion through their skin (therefore, they don’t have lungs). Their small size also means their brains are about the size of a very small piece of orzo. All of their life functions and behaviors are products of a relatively basic operating system.

That makes their complex mating behaviors even more astounding. The males will do little dances around females. The males also have a gland on the underside of their chins (this is actually how you sex them in the field) which they “snap” on the female to make them… frisky. When she is ready, she’ll nudge him with her face and he releases little sperm packets in a little line. She walks over them and picks them up with her cloaca (use context clues if you don’t know what a cloaca is). No hanky panky- as we know it. But this system has worked well enough for millions of years for these little guys.

Mate fidelity during single breeding seasons has been known to occur in Plethodontids. However, one species has taken it to the next level. There’s this one study in which mate punishment was observed in Plethodon cinerus. By mate punishment, I mean females will beat up their mate if she detects another female’s scent on him. Sometime’s he’ll sneak off and “slip up” with the female from the rock down the stream. When he comes back, his main lady will bite, bump him, smack him, and generally abuse him. Mind you, they’re no more than 2 inches long. So this is especially funny. Scientists observed that the male does not fight back, but instead just takes it. He knows what he did. Reminds you of a bipedal primate, huh?

We humans display mate punishment too. Be it yelling, hitting, revenge, or the silent treatment, we participate in just the behavior. Luckily, we are civilized and (some of us) know to beat down feelings of petulance and handle such issues with grace and maturity. However, could it be that our jealous romantic retribution is an evolutionary seed planted long ago in our history, as in the case of these slutamanders? Or is it the result of Jersey Shore showing us how Sammy Sweetheart makes Ronnie regret his infidelities?

As usual…. probably both. Isn't it something how this behavior is characteristic of a brain the size of orzo AND a brain the size of a football? We have more in common with our terrestrial tetrapod friends than just morphology. It's important to remember that behaviors evolve too.

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