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Random question about starfish

1 Post author: Raemon 05 August 2012 02:31AM

Anyone know how long a starfish can survive on land, and if it matters especially whether there is a hot sun.

I promise this will turn out to be (at least somewhat) important and Less-Wrong relevant. Googling for the answer gives me a bunch of "wiki-answers" type sites that I don't trust and news articles that don't give me the specifics. If anyone either has marine-biologist cred, or better google-fu than me, I'd appreciate it.

Comments (17)

Comment author: [deleted] 05 August 2012 06:43:32AM *  12 points [-]

Short answer: It depends, and it varies by the type. "Starfish" isn't a very specific term, after all.

Taking extremes, some cannot survive any significant exposure to air; even a few seconds is lethal -- crown-of-thorns can easily rupture on exposure to air and leak all their body fluids out rapidly. Others, such as ochre stars (a common species on the Pacific Northwest coast of North America) pump themselves full of seawater and then cling tightly to a rock with their hydrostatic tube-feet, retaining water as a heat sink and simply waiting out the high tide. Even species that aren't especially resilient to air exposure may take days to fully die, despite having undergone lethal exposure.

Comment author: Raemon 05 August 2012 05:01:44PM 1 point [-]

Thanks!

Comment author: RichardKennaway 05 August 2012 09:14:07AM 4 points [-]

Is this leading up to an assessment of the accuracy of the parable about throwing a starfish back into the sea? (Punchline: "vg znqr n qvssrerapr gb gung bar".)

If you search inside this book for the word "starfish" there's a chapter-length telling of that story (the whole book being an elaboration of the parable), with some concrete details of what happens to stranded starfishes of at least one sort, on at least one beach somewhere.

Comment author: TrE 05 August 2012 04:12:26AM *  4 points [-]

I was searching for "asteroidea" (biological term for sea stars) on google scholar, and found the term "desiccation" alongside it. So I did a search for exactly that, but found no exact time spans. However, it seems like some sea star species have to survive periods of dryness during tides, so I'd say 12 hours should be about a maximum. Just a wild guess, though. It apparently matters if there is sun or not as heat will dry them out quickly.

Anyway, I learned a lot about sea stars in the process

Comment author: Raemon 05 August 2012 04:40:34AM *  3 points [-]

Thanks.

asteroidea (biological term for sea stars)

This makes my own searches make far more sense. Articles kept talking about asteroids and I was so confused.

Comment author: TrE 05 August 2012 04:43:37AM 0 points [-]

Glad I could help (somewhat).

Comment author: Raemon 05 August 2012 05:41:29AM 0 points [-]

Helped, at least insofar as I'm unlikely to be grossly wrong about something in a way the average smart person can debunk.

Comment author: TrE 05 August 2012 08:47:52AM 0 points [-]

What is it? Some sort of story, a game, or an analyzing article?

Comment author: Raemon 05 August 2012 03:10:39PM 3 points [-]

I like cultivating an air of mystery before a reveal.

Comment author: NancyLebovitz 05 August 2012 06:36:26AM 0 points [-]

Humidity level should matter, too.

Comment author: Nisan 05 August 2012 06:48:50AM 2 points [-]

I have a feeling that you're about to do something very interesting, and I look forward to bearing about it!

Comment author: Raemon 06 August 2012 04:45:18PM *  0 points [-]

Thanks all. Originally thought I'd get this done within a day or two, but right now its looking like about 2 weeks before I post the end product. (I want to believe next weekend, but you know, planning fallacy and such)

In the meantime... it says there are 13 comments but I see twelve. Hmrr?

Comment author: Wei_Dai 09 August 2012 09:05:43PM 0 points [-]

In the meantime... it says there are 13 comments but I see twelve. Hmrr?

There's an additional spam comment that has been hidden (presumably by a moderator, unless there's an automated spam filter here that I don't know about).

Comment author: Alicorn 09 August 2012 10:14:59PM *  0 points [-]

There is a banned spam comment. I remember banning some comments like it but don't remember if this one in particular was me.

Comment author: Vladimir_Nesov 09 August 2012 10:05:09PM 0 points [-]

Reported to the bug tracker.

Comment author: prase 06 August 2012 11:40:25PM *  0 points [-]

Adding a comment to see how the number changes.

Edit: written 14 and visible 13. Bizarre.