Jump to content

Woah


Jbrougher

Recommended Posts

Ok, we are talking about two animals that are fairly common in the ocean. I am not sure this is much different from adding shrimp or damsels to feed a frogfish. And we could easily debate that keeping them in an aquarium is even more cruel.

Don't get me wrong....I am not advicating this as a new olympic sport, but this is more like feeding mice to snakes, not backyard dogfighting.

Good or bad, it is pretty cool to see.

Link to comment
Share on other sites

All respect, but have to disagree with you on that one Prof. Roosters and dogs fight in the wild as well but putting them together for sport or entertainment doesn't make it right. I don't think any of us would intentionally feed an octopus to a shrimp when other foods are much more readily available and cheaper. This just seemed in bad taste to me.

Oh, and I'll be taking the calamari for an appetizer....

Link to comment
Share on other sites

Yea, This just seems like cruelty. I don't think either of these animals are really "standard" food items for the other. The Mantis won the fight but will probably die from toxins so it's not like they were really "feeding" it. Don't get me wrong. I drop live food to my animals all the time but this was hunting for entertainments sake and seems more akin to dog fighting than to feeding.

That being said, you are right that from the sense of seeing what these animals can do it was pretty cool. I've never seen that good footage of a mantis's "punch" before.

Link to comment
Share on other sites

i agree 100% with the prof on this one, we love to say things that make us feel better but if you where a fish would you really want to leave the ocean for a aquarium?

you can say you tank is big enough all day long but its not and it never will be

I'm not trying to make a big deal about this 'discussion' but I have to dissagree whole heartedly with this attitude. Frankly, there is a long debate that could be had about how humane aquariums and aquariums owners are and lord knows nature is sometimes just down right viscous. But none of this addresses the 'fight'. In this instance someone put two animals together for the express purpose of seeing WHICH WOULD DIE FIRST and there is nothing redeeming about that. It's just flat out wrong!! IMHO

Bill

Link to comment
Share on other sites

In this instance someone put two animals together for the express purpose of seeing WHICH WOULD DIE FIRST and there is nothing redeeming about that.

Maybe I missed something, but how do you know why this was done?

My point above was that this video wasn't shot by some random hobbyist; it was shot by a guy who has been researching mantis shrimp for decades. I think it's safe to assume that he didn't do it for entertainment.

Link to comment
Share on other sites

Ok, here's what the cruel, horrible man who shot the video had to say about it:

The purpose of feeding the H. lunulata to the O. scyllarus was part ofa larger line of study examining coevolutionary arms races. Inparticular we are interested in how predator and prey interact and dealwith various offensive and defensive morphologies and behaviors. Theanimals were not put together for our entertainment. I wanted to ask afairly basic initial question - would a stomatopod that occurssympatrically with a blue-ring attack it? We generally think that thecoloration of blue-rings is aposomatic, but aside from people usuallyavoiding them because they recognize the blue-rings and have been toldby other humans that they are dangerous, I know of no data that thatdemonstrate that the blue rings serve as a warning to any other speciesthat might play the role of "predator". The next question to ask ifthere was avoidance would be whether this behavior was learned ofinnate? Similar research has been done on other aposomatic systems suchas mot-mots and coral snakes, yellow-bellied sea snakes exposed topredatory fish or herons and egrets, etc. It has not been done withblue-rings. Making the question even more interesting from anevolutionary perspective is the fact that both H. lunulata and O.scyllarus have indeterminate growth so it is possible for theirinteractions to vary with different size relationships - largestomatopods might be able to kill and/or eat smaller blue-rings andlarge blue-rings might be able to prey of smaller stomatopod. Thiscould considerably complicate the dynamics. It would seem moredifficult for an innate avoidance to evolve under these circumstancesor even possibly a learned one.

So where do you start exploring such a question. I would prefer to makemy initial observations in the field watching blue-rings andstomatopods interact, but such observations are extremely difficult andeven if you are persistent and patient enough to see a few encounters,you have little control over the participants, their size, physiology,motivation, experience, etc. Aside from those who are opposed tocarnivores killing and eating prey, I assume most people would notobject to this type of research. Bringing the animals into thelaboratory gives us much more control over the interactions. First, Ican control the predator making sure that it is hungry my depriving itof food for a specified period, making sure that it is not approachinga molt, etc. If it doesn't attack the octopus, I know that it is notsimply avoiding the blue-ring because it isn't hungry. It is alsoeasier to control the size relationship between the two and to assaythe blue-ring to determine how much TTX it contains and/or delivers.(The former is done through chemical analysis; the later by giving theoctopus a live grass shrimp, waiting a prescribed period after theinitial attack, removing the shrimp and analyzing it to see how muchTTX it contains.)

While the intereaction was staged, it was done in a very large tank(200 gal) with lots of rock into which the participants could escape.The stomatopod did have a pvc burrow, but it would have an even betterone in the field.

When I presented the blue-ring to the stomatopod, I expected one ofthree outcomes. Most likely I thought, the stomatopod would flee orsimply ignore the octopus. If so, I was interested to see if theblue-ring would also flee, do nothing, or attack (but these aredifferent questions from what I was primarily interested in.)Alternatively, the stomatopod could attack driving off or killing theblue-ring. The third alternative, which I did not expect, was that thestomatopod would kill and eat the blue-ring.

As you saw, the later happened. What you did not see was that thestomatopod continued to pound the octopus for about 25 minutes, longafter it was initially disabled, and then killed. Several times duringthis period, the stomatopod appeared to sample the octopus, jumped backand extensively cleaned its mouth parts. Finally, it ate the entirecorpse. We watched the stomatopod for several days and it seemed noworse for the meal. When offered another blue-ring, it also attackedand ate it suggesting that it had not learned to avoid them. In fact,there seemed to be no reason to.

What is interesting here is the behavior of the predator. I've watchedstomatopods kill and eat other species of octopus and I had never seenthis extended period of processing. This suggested to me that the O.scyllarus was mechanically removing the TTX containing venom from thedead blue-ring by repeatedly pounding and manipulating it. Of coursethere also remains the possibility that some stomatopods such as O.scyllarus have evolved resistance to TTX, perhaps by modification oftheir sodium channels as has occurred in garter snake populations thatprey on TTX containing newts. We are indeed conducting the obviousexperiments of feeding predators pieces of shrimp injected with TTX,injecting TTX directly into stomatopods, etc. However, to test themechanical processing hypothesis, we have to measure the TTX containedin a prey animal before and after a stomatopod has processed it.Further questions would then consider whether the processing behavioris learned or innate, what happens as the size of the prey approachesthat of the prey, are small O. scyllarus resistant to attacks bypredatory blue-rings, etc. If it turns out that O. scyllarus areresistant to TTX, then we would like to know if this occurs in otherspecies that occur with or do not occur with blue-rings.

I see this as a legitimate and ethical line of research. Clearly thereare issues related to any research involving predator - preyrelationships. We try to minimize the number of animals used andcertainly try to avoid threatened species, etc. However, often thequestion dictates what species are used. In this case, it happens to beblue-rings - not because they are "beautiful", but because they containTTX and have what appears to be aposomatic coloration and we would liketo understand how such systems coevolve and function.

I do not stage "**** fights" to satisfy my own or anyone else's desireto be titillated. I have advised on various nature films that may haveincluded fighting and predation sequences, but in that context neitherI or my science have been attacked. In fact some of the same people whoseem so affended by this sequence have praised those very films.

(By the way, I was not an advisor on "Incredible Suckers" although Ihave worked with Mike several times and I've discussed the H. fasciatasequence with him. The blue-ring - stomatopod encounter was staged inan aquarium, was between a blue-ring and stomatopods that do not occurtogether, and came to a conclusion that I think was not justified. Ifyou look carefully at the sequence, there are at least two differentstomatopods used. The first one injured the octopus and was replaced bythe second. The story told was that blue-rings release venom to killprey at a distance. This has not been fully documented and our attemptsto replicate it have failed. I suspect that in this case if thestomatopod was killed by venom, it was probably because the injuredoctopus was "leaking" saliva due to being stabbed.)

O.K., I've rambled on long enough. I can take personal criticism, butwhen people feel that they can attack the quality of science beingconducted in my laboratory, I take it personally. It was clearly amistake to post that clip and I will do my best to have it purged fromthe web.

Link

Link to comment
Share on other sites

For such a well respected scientist WTF is wrong with his space bar? For real. I can't take a thing he has to say seriously.

As an owner of blue ring octopus, I will continue to stay out of this discussion. I am sure you already know what I think about it all.

Mike, I do apologize for offending your refined sense of typographic propriety. However, all blame should fall on my shoulders, and not those of Dr. Caldwell. The spaces are not missing on the original page, the one linked to at the bottom of the quotation. I'm not sure how it happened, but somehow they were removed in the act of cutting and pasting. If you haven't been overly offended, maybe you'll take the time to click on that link. Knowing now that you keep a Blue-ringed Octopus, I would like especially to hear your opinion on this. I'm particularly interested in whether you think the observations described in Dr. Caldwell's brief letter do more to advance our understanding of these species, than say, you or I keeping one in a small glass box, where little or nothing of scientific value is ever learned.

I'm not trying to be a jerk about this; I am, however, quite surprised at the anti-science attitude displayed in most of the above posts.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...