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| Hi Ron, Having thrown my harlequin shrimp page out to the public, I've had, for the first time, been asked if it was true that harlequin shrimp inject their starfish prey with a toxin to knock them out so that they can feed on it. Off the top of my head, this would not make sense for the shrimp to do so, for one, toxins for any animal are an expensive thing to produce and maintain. That and I have never heard of any shrimp species being anything close to toxic. I mean, if one species evolved the use of toxin(s), and was such a cheap thing to do, wouldn't there be a great many shrimp species swimming about daring fish to eat them? I think its just a matter of the shrimp using brute force to flip the starfish and then hold them in place untill the starfish just gives up, all the while, the shrimp are digging holes into the starfishes arm(s) and always do the arms first, which usualy leads to most of the arms being cut off. (at least two always) That in itself would make them unable to move, or unwilling to move, specialy if they are also being sat upon and not allowed to right themselves, I would think. Chuck
___________________________________________________________ "My life is free now, my life is dear" - Black Sabbath
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Hi,
There are no shrimp toxins at play here. Many stars are "distasteful" and it is often proposed that this has an anti-predator function, but in most cases that is also just conjecture. It seems more likely that sea star metabolism simply produces chemicals that may confer some protection. Not many things do eat sea stars, but as far as I know, none of those animals that do so rely on any sort of chemical means. They simply either tear the sea star apart and eat it, or attach themselves to it and eat it.
Cheers, Ron
"The difference in mind between man and the higher animals, great as it is, certainly is one of degree and not of kind. The love for all living creatures is the most noble attribute of man." Charles Darwin (1809-1882)
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Group: Moderators
Last Login: Today @ 10:44:42 PM
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| Thanks Ron, that sure makes a lot more sense to me than a shrimp capable of invenomating its food. I suspect that this myth came about simply because the shrimp's feeding claws look very needle or fang like. That and most starfish seem to become subdued fairly quickly once flipped over or pounced on by a pair of harlequins. The first thing a starfish would do when flipped or attacked is to withdraw as much as possible and only venture a movement when all is still again. Having a shrimp parked on top of it while constantly picking / tearing at it, would keep the starfish constantly withdrawn, thus constantly immobile. I can see now where such an observation could be mistaken as the starfish having been "knocked out". Chuck
___________________________________________________________ "My life is free now, my life is dear" - Black Sabbath
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