Monthly Archives: April 2010

You Should Probably Just Move Oceans, Male Gulf Pipefish

It’s well-known that within seahorse circles, it’s the males who bear the responsibility of pregnancy, not the females. The same goes for their relatives, the pipefish, whose males are equipped with a specialised external brood pouch into which the females will deposit eggs during copulation. But a recent examination of  pipefish male pregnancy and mate selection by Kimberley Paczolt and Adam Jones from Texas A&M University has found that this process is nothing to coo over, Henry Gee, Senior Editor at Nature, describing it as “sinister.”

Observing the reproductive behaviour of 22 captive male Gulf pipefish (Syngnathus scovelli), a small-mouthed, pencil-shaped species with a relatively poor swimming technique, Paczolt and Jones discovered just how much control the males have over their prospective progeny. By pairing the males with either large or small females, they found that that the males wasted no time in mating with larger, more attractive females, but were significantly less eager when paired with smaller females. What they also found is that the eggs deposited by larger females had a much higher rate of survival to the point of birth, the males selectively aborting those from a less attractive partner by either retaining vital nutrients, or absorbing (ie cannibalising) the embryos.

By also looking at successive pregnancies in male pipefish, the team were able to make sense of their rather callous tendencies. Not only did broods from smaller females have a low survival rate to begin with, but if a male first mates with an attractive female and bears a large brood, he’s unlikely to want to invest more resources into a following pregnancy, particularly from a less attractive partner. Instead of nurturing these offspring, his specially evolved brood pouch allows him to retain or absorb the nutrients to ready himself for the possibility of meeting a more attractive mate. “When a male mates with a female that’s not necessarily all that ‘attractive,’ instead of investing a lot in those offspring, he’s recharging for the next pregnancy – at least this is what our results suggest,” Dr Jones reports.

That the male pipefish are actively trying to control the quality of their offspring during pregnancy is evidence of post-copulatory sexual selection, which follows the initial competition for mates by way of combat and elaborate courtship displays. Dr Jones explains, “When Darwin proposed the theory of sexual selection, he dealt entirely with pre-mating sexual selection… But after mating there are things that happen within the female’s reproductive tract or competition among sperm from different males that also results in sexual selection. So it turns out that post-mating sexual selection has hardly been studied at all in these sex role-reversed species.”

Well Gulf Pipefish Boys, you might think this is all pretty great, being able to pick and choose (and cannibalise) your own progeny with nary a qualm in the world. But the thing is, those ugly pipefish girls you mated with in the past, they’re not just going to disappear. The ocean might be big, but it’s not that big, and you know what they say – “Mate with one ugly pipefish that time you had nine vodkas, three gins and no dinner, and you’ll end up with six months of whiny text messages and a lifetime of really awkward encounters whenever you try and go back to that particular bar because they happen to serve $5 spirits till 1am.”

So you’ll decide to brave said bar one night, all, “Five tequila sunrises please. Yes, I’m serious. Oh. Hi…”

And that unattractive pipefish girl you once mated with, let’s call her… Martin, will be like, “OMG, I haven’t seen you in ages. How are the offspring?”

“Huh?”

“You know, the offspring. Our offspring?”

“Oh. Umm. Hmm.”

“You ate them, didn’t you?”

“Well technically I absorbed… Shit. Five more tequila sunrises please.”

But it won’t end there, Gulf Pipefish Boys, with you simultaneously drinking and wearing a good deal of very cheap alcohol and orange juice, because everyone will know about that time you mated with Martin, especially her really short and ugly friends, and they’ll look at her and then at you and then back at her and figure they’ve got a shot.

So you’ll be at a completely different bar, trying to chat up some cute pipefish girl who really likes the Internet and stuff, like, “I aborted a brood twenty hoping to meet someone so… long. How many millimetres are you anyway? A hundred and twenty? Hundred and thirty? Wait right there, I’m going to get you a vat of gin.”

“And a Redbull.”

“And a Rebull. Right.”

But you’ll only get halfway to the bar before a bunch of Martin’s short and ugly friends swarm and engulf you, all, “Hey can I buy you a drink?”

“No thanks.”

“You want my number? I might be only ninety-five millimetres, but I sure know how to use them…”

“Ew. No thanks.”

“Hey can I buy you a drink?”

And meanwhile the cute pipefish girl who really likes the Internet and stuff will fully think you’re into ugly chicks or something and clear off without her vat of gin, or Redbull, and you’ll either have to go home alone, or pick one of the short and ugly pipefish girls to take with you, like, “Alright, fine. You. What’s your name? Brian? Yeah okay, whatever, come on.”

And you thought having a brood pouch would be a riot, Gulf Pipefish Boys.

More info from Not Exactly Rocket Science and Grrl Scientist // Original paper in Nature // Image from Reef Scavengers

Edit: I’m entering this post for the The National Evolutionary Synthesis Center’s Travel Award competition, which awards a $750 grant to two bloggers to attend ScienceOnline2011, a science communication conference held on January 13-15, 2011, in North Carolina. The best posts that highlight current or emerging evolutionary research appearing in peer-reviewed literature within the last five years win, so fingers crossed tightly for me please!!

– bec

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Filed under Science, Sea Creatures, Video

Assassin Bug, What Do You Mean You’ve Never Seen The Jackal?

A study from Sydney’s Macquarie University has examined the predatory behaviour of the assassin bug (Stenolemus bituberus), describing for the first time the two distinct attack methods used by this araneophagic (spider-eating) insect. Putting the bugs in contact with five species of web-building spiders, Anne Wignall observed the assassin bugs to use either “stalking” or “luring” tactics to hunt their prey in their webs.

When stalking, the assassin bugs will rely on stealth to reach their prey undetected, severing and stretching the silk threads of the web between itself and the spider, and approaching it with an irregular, bouncing locomotion. Exploiting periods of environmental disturbance (caused by wind, for example), together with the vibrations created by its cryptic stepping movements, the assassin bug creates a kind of “smokescreen” effect to mask its approach.

When luring, however, the assassin bug will manipulate the silk vibrations to deliberately reveal its location on the web and draw the spider to it, plucking the threads to emulate the twitching, panicked movements of ensnared prey for up to twenty minutes. “The spider thinks it’s getting a meal, but instead gets eaten itself,” says Wignall.

Prior to striking and killing the spider when in reach, the assassin bugs were observed to engage in unusual behaviour known as “prey tapping.” The assassin bug will tap its prey from above with its antennae to apparently reduce its ability to respond to the impending attack, Robert Jackson of the International Centre of Insect Physiology and Ecology in Kenya likening its effect to that of hypnotism.

Now this is all very elaborate and apparently successful, but we all know spiders are not that stupid. Lord knows if one asked me to do something, I sure as hell wouldn’t refuse, so they’ve definitely got something there. Plus we all know spiders talk,* which could make life pretty difficult for those assassin bugs I’d imagine. Because you can’t be an assassin if your victims can see you and your wide-open bag of tricks coming, right?

So poor Assassin Bug would finally get an assignment, which is awesome because he’s just been sitting at home doing fuck-all for months because the pickings are slim when there are so many other assassin bugs around. It’s like, “Hey, so I heard an Achaearanea extridium moved in down town?”

“Yeah, Lindsay already picked him off last week.”

Motherfucker.”

He would manage to finish Mass Effect 2 in like 20 hours, sort his entire mp3 library by sub genre and bpm, plus read a bunch of chess endgame books he found under his bed, so it wouldn’t be a total loss, but having not eaten in months, he’ll have spent most of his unemployment either snapping at people on the street who asked him for the time (“Do I look like I can afford a watch? Jesus.”), or passed out in a hungry stupour.

But then his agent (or whatever the guy who organises these things is called) will call him up like, “The Pholcus phalangioides who moved into the Achaearanea extridium’s place…” and the Assassin Bug will be all,

“You serious?!”

“Just hang up.”

“Okay. Sorry.”

He’ll head to the Pholcus phalangioides’ web, knocking off a bystanding snail on the way because it looked at him funny, and then the caterpillar barista who accidentally burnt his coffee because it was the first one he’s been able to afford in forever and he was really looking forward to it. He’ll also kill the terrified kitchen-hand who will try to make him another one but can’t froth the milk properly because he only knows how to wash dishes because he dropped out of high school to be a musician, only to be kicked out of a really shit band after one rehursal because he didn’t know what a chord was.

Then at the Pholcus phalangioides’ web he’ll be plucking and stretching like mad for like ten minutes before Pholcus phalangioides will come over all, “Do you mind? I have to get up early tomorrow. Get the fuck off my web.”

The desperate Assassin Bug will rush over and start tapping him on the head all, “Oooooh…. Oooooh….!”

“Oh my God, Stop it. I’m going back to bed.”

“Oh. Okay. Sorry.”

And the Assassin Bug will look so pathetic that the Pholcus phalangioides will feel sorry for him and be like, “You’ve seen The Jackal, right?”

“The one with Bruce Willis?”

“Yeah.”

“No…?”

“Okay well anyway, there’s this scene with a boombox–”

“A boombox?”

“What.”

“Who the hell calls them boomboxes?”

“Do you want my advice or not?”

“Okay. Sorry.”

“Anyway, there’s this scene with a boombox…”

Then later that night the Pholcus phalangioides will be woken up again, this time by some excessively loud bad techno and he’ll stumble sleepily out of his curled-up dead leaf going, “Oh my god, Assassin Bug, you can’t use my own advice on me! What is the matter with you?”

The next morning the Assassin Bug’s agent (or whatever the guy who organises these things is called) will leave a message on his machine all like, “Why the fuck is that Pholcus phalangioides still alive? Why the fuck didn’t I use one of my other guys? You arsehole. Wait, what is all that racket? What did I tell you kids about raves on my front porch?! Oh, its you. I was just– Uggggh….”

* Which is why you should never kill one unless you want five more to come to their funeral.

Journal of Ethology Paper // New Scientist for the video that inexplicably won’t embed // Top picture from Jeffrey Friedl’s blog

– bec

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Filed under Insects, Science

Wandering Ponies #4

Ahh, the Internet.

It’s been a while between Wandering Ponies and the Internet has been providing some mad lolz of late, so bear with me while I indulge. Or you know, try and enjoy the mad lolz. If that’s what you’re into. I’m not one to assume. Plus you look like a busy person. You probably don’t have time for mad lolz. I don’t know. Hey nice tie. What are those, birds? Yeah that’s cool. Hey do you reckon you could make an entire tie out of a bird? That would be wild. It’d have to be a pretty big bird though. What? Oh okay, you’re busy. Sorry, just saying I like your tie. Jesus.

Anyway, first up, one of the best services the Internet has provided in, I don’t know, a long time: BIG ASS MESSAGE. Perfect for those times when you need to ask this, or this.

When it comes time to give your kids Teh Drugs Talk, best you don’t show them this. Because giant teddy bears who cough up business men and whack giant pigeons with street lamps are AMAZING:

Novelty Tumblrs make me infinitely happy, and these two are among the best new ones around. There’s Godzilla Haiku, because you might be a hungry reptile the size of a twenty-storey building, but that doesn’t mean you don’t have feelings. And Michael Buble Being Stalked By A Velociraptor. Because dude has it coming to him.

Next, if you think Running Ponies has an unhealthy obsession with sex, and sea creatures, and sex, you obviously haven’t visited the Hectocotyli blog. Dude makes even me blush. And giggle like a school girl. Or both, simultaneously.

And finally, because everyone these days seems to have forgotten what ACTING is about, I give you: DEATH DISC:

Balloon horse by Andrea Galvani

Happy Easter.

– bec xox

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