Comments on: Why is The Giant Isopod Giant? http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/ All the news on the Earth's largest environment. Wed, 17 Mar 2010 02:37:00 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: Giant Isopod Fail | Deep Sea News http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/comment-page-1/#comment-7786 Giant Isopod Fail | Deep Sea News Wed, 22 Jul 2009 03:32:27 +0000 http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/#comment-7786 [...] is a giant [...] [...] is a giant [...]

]]> By: JOHN L http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/comment-page-1/#comment-7535 JOHN L Fri, 10 Jul 2009 19:55:57 +0000 http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/#comment-7535 I want to find out that can deep sea isopop be sea food? I want to find out that can deep sea isopop be sea food?

]]> By: JSL and Giant Isopods | Deep Sea News http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/comment-page-1/#comment-7035 JSL and Giant Isopods | Deep Sea News Sun, 31 May 2009 15:28:15 +0000 http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/#comment-7035 [...] why deep-sea organisms are the size they are? Often a single observation of singe item or event stimulates a single question you spend the rest of your life trying to answer. Of course, I other remember many other things about my first submersible dives on the JSL.  I was [...] [...] why deep-sea organisms are the size they are? Often a single observation of singe item or event stimulates a single question you spend the rest of your life trying to answer. Of course, I other remember many other things about my first submersible dives on the JSL.  I was [...]

]]> By: kevin z http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/comment-page-1/#comment-528 kevin z Wed, 26 Mar 2008 22:30:06 +0000 http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/#comment-528 I believe that researchers at Texas A&M have them in aquaria. I have a paper on that I can send if you are interested I believe that researchers at Texas A&M have them in aquaria. I have a paper on that I can send if you are interested

]]> By: Clint http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/comment-page-1/#comment-527 Clint Wed, 26 Mar 2008 17:53:28 +0000 http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/#comment-527 Do they make good pets? I would love one of those guys! Do they make good pets? I would love one of those guys!

]]> By: Kevin Zelnio http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/comment-page-1/#comment-526 Kevin Zelnio Thu, 05 Apr 2007 17:53:23 +0000 http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/#comment-526 The genus Bathynomus currently comprises of 11 species, the last one described in 2004 from Thailand. 8 of these have vertical ranges below Craig's Definition of Deep (CDD). There many types of isopods in the deep sea and they are very common. They range in size from minute to large and different body forms and life histories. I'll try to highlight some of the more obscure and interesting ones in future. Isoods are very common in all environments, even freshwater and terrestrial. Check out the world database of isopods at: <a href="http://www.nmnh.si.edu/iz/isopod/" rel="nofollow">http://www.nmnh.si.edu/iz/isopod/</a> Looking at gigantism within the isopods is a great idea, one I would like to pursue in the future if I had the time and resources. In fact the genus Bathynomus is great place to start since the vertical range of the genus is 22-2140m and many species have wide horizontal distributions. Unfortunately, getting sample sizes of lots of different species from different depths to attain the statistical power to test hypotheses is the limiting factor. Resource availability for B. giganteus is probably very intermittent. Some days a nice tuna falls on your lap, other days nothing. If they hang around methane seeps or deep-sea coral reefs, they potentially have the opportunity to be "regular" to the scene and scavenge or be a facultative predator on other inhabitants of seeps or reefs. There may indeed be seasonality in the deep sea in terms of the amount of biomass that falls down from the surface during productive seasons versus non-productive seasons. This could definitely have an effect on the observed seasonality of reproduction in B. giganteus. More experimentation is needed to get at the correlation though. The genus Bathynomus currently comprises of 11 species, the last one described in 2004 from Thailand. 8 of these have vertical ranges below Craig’s Definition of Deep (CDD). There many types of isopods in the deep sea and they are very common. They range in size from minute to large and different body forms and life histories. I’ll try to highlight some of the more obscure and interesting ones in future.

Isoods are very common in all environments, even freshwater and terrestrial. Check out the world database of isopods at: http://www.nmnh.si.edu/iz/isopod/

Looking at gigantism within the isopods is a great idea, one I would like to pursue in the future if I had the time and resources. In fact the genus Bathynomus is great place to start since the vertical range of the genus is 22-2140m and many species have wide horizontal distributions. Unfortunately, getting sample sizes of lots of different species from different depths to attain the statistical power to test hypotheses is the limiting factor.

Resource availability for B. giganteus is probably very intermittent. Some days a nice tuna falls on your lap, other days nothing. If they hang around methane seeps or deep-sea coral reefs, they potentially have the opportunity to be “regular” to the scene and scavenge or be a facultative predator on other inhabitants of seeps or reefs.

There may indeed be seasonality in the deep sea in terms of the amount of biomass that falls down from the surface during productive seasons versus non-productive seasons. This could definitely have an effect on the observed seasonality of reproduction in B. giganteus. More experimentation is needed to get at the correlation though.

]]> By: CR McClain http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/comment-page-1/#comment-525 CR McClain Thu, 05 Apr 2007 15:26:25 +0000 http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/#comment-525 Actually, the idea of a random walk is mine, size doesn't necessarily need to be advantageous just not disadvantageous. Gould's point is the same one you make which what is the trend among all isopods (there are lots of others)and the futility of focusing on just one. As far as other isopods some definitely do get larger (but not others) but none like Bathynomus a very unique case. What is the resource availability for these guys? Is there always something to scavenge or prey upon? Is there seasonal or other variation? Is it predictable? Definite variation and patchiness through space and time so the fasting potential becomes important. Actually, the idea of a random walk is mine, size doesn’t necessarily need to be advantageous just not disadvantageous. Gould’s point is the same one you make which what is the trend among all isopods (there are lots of others)and the futility of focusing on just one. As far as other isopods some definitely do get larger (but not others) but none like Bathynomus a very unique case.

What is the resource availability for these guys? Is there always something to scavenge or prey upon? Is there seasonal or other variation? Is it predictable? Definite variation and patchiness through space and time so the fasting potential becomes important.

]]> By: Jim Lemire http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/comment-page-1/#comment-524 Jim Lemire Thu, 05 Apr 2007 15:15:12 +0000 http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/#comment-524 Ok, stream of consciousness of a sort here: I get the idea that Gould's quote is making, but a giant, deep-sea isopod as a result of an evolutionary random walk? I'm skeptical of that one. It would be nice to know how their growth rate compares to other isopods. Speaking of other isopods, are there any other deep-sea varieties? Or is Bathynomus giganteus the only one. If there are others, are they also larger than normal? Conversely, are there other (non-deep-sea) gigantic isopods out there and if so, where do they live? Instead of looking at gigantism as a whole or even within arthropods, what if we focus only on isopods? What is the pattern then? I like the larger-size-for-times-of-famine idea. What is the resource availability for these guys? Is there always something to scavenge or prey upon? Is there seasonal or other variation? Is it predictable? sorry I can't offer answers, just more questions. (BTW it's totally out of character and irrelevant, but I think isopods are gross, along with millipedes, and the giant versions are really gross. Nightmarish even. *chills*) Ok, stream of consciousness of a sort here:

I get the idea that Gould’s quote is making, but a giant, deep-sea isopod as a result of an evolutionary random walk? I’m skeptical of that one. It would be nice to know how their growth rate compares to other isopods. Speaking of other isopods, are there any other deep-sea varieties? Or is Bathynomus giganteus the only one. If there are others, are they also larger than normal? Conversely, are there other (non-deep-sea) gigantic isopods out there and if so, where do they live? Instead of looking at gigantism as a whole or even within arthropods, what if we focus only on isopods? What is the pattern then?

I like the larger-size-for-times-of-famine idea. What is the resource availability for these guys? Is there always something to scavenge or prey upon? Is there seasonal or other variation? Is it predictable?

sorry I can’t offer answers, just more questions.

(BTW it’s totally out of character and irrelevant, but I think isopods are gross, along with millipedes, and the giant versions are really gross. Nightmarish even. *chills*)

]]> By: Kevin Zelnio http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/comment-page-1/#comment-523 Kevin Zelnio Thu, 05 Apr 2007 12:19:21 +0000 http://deepseanews.com/2007/04/why-is-the-giant-isopod-giant/#comment-523 In regards to the last question, the maximum reported size of Bathynomus giganteus is likely to be an artifact of our sampling. On the contrary, Briones-Fourzan and Lozano-Alvarez have done most of the ecology of this isopod in the Gulf of Mexico and have amassed a large sample size (almost 1600 individuals - Barradas-Ortiz et al. 2003), yet their max. size was 36.3 cm, about the size of the one trying to rip my throat out above. More morphometric analysis needs to be done correlating size to depth, oxygen concentration, temperature etc. using Canonical correspondence analysis or something similar to tease apart the variables limiting its size. It would be great to get growth rate data, I wonder if one could follow it in aquaria and measure adult growth after each molt. In regards to the last question, the maximum reported size of Bathynomus giganteus is likely to be an artifact of our sampling.

On the contrary, Briones-Fourzan and Lozano-Alvarez have done most of the ecology of this isopod in the Gulf of Mexico and have amassed a large sample size (almost 1600 individuals – Barradas-Ortiz et al. 2003), yet their max. size was 36.3 cm, about the size of the one trying to rip my throat out above.

More morphometric analysis needs to be done correlating size to depth, oxygen concentration, temperature etc. using Canonical correspondence analysis or something similar to tease apart the variables limiting its size. It would be great to get growth rate data, I wonder if one could follow it in aquaria and measure adult growth after each molt.

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