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Coming attractions

A Blog Around The Clock posted a preview of the cover for The Open Laboratory: The Best In Science Writing on Blogs, The 2008 Edition. As noted previously, it'll feature a post from this blog. It should be available, like the the 2006 and 2007 editions, at Lulu.

How do you like your algae? Crisp!

We're always on the lookout for food items that Marmorkrebs like, but that are convenient in requiring little handling or preparation time. Frederike Alwes tipped us off to TetraAlgae Tropical Crisps, which bigger, dedicated pet stores should have. Marmorkrebs really seem to enjoy it, which surprised me a little. Several other kinds of algae tablets I've tried in the past were mostly ignored.

Apologies to all the non-Canadians who don't get the ancient Coffee Crisp ad reference in the post title.

Pic of the moment: 26 January 2009

Marmorkrebs / Marbled Crayfish (Procambarus spec.)
Originally uploaded by Sexecutioner

Spotted on Flickr.

Shameless self-promotion

I have a new review article out that has strong ties to this website, although it's not apparent from reading the article. So here's the scientific equivalent of a deleted scene on a movie DVD.

The review concerns the evolution of giant neurons responsible for escape responses in decapod crustaceans. This line of research, mostly using crayfish, was particularly fruitful in the 1970s and 1980s, but research on the escape system has waned to some degree since then. This is not to say there hasn't been good science on these neurons – there has – but I think it's fair to say less prominent than it was.

In writing the article, I thought a lot about why this line of research has waned, and what remains undone with research on the escape system. This is a paragraph from an earlier draft of the manuscript (written about January 2007) that didn't make it into the final published edit.

The revolutions in genetics and development have barely touched crustacean research when compared to other organisms. Currently, only one crustacean, the non-decapod Daphnia pulex (Colbourne et al. 2005), is having its genome sequenced, in comparison to about a dozen genome projects for insects besides Drosophila. Similarly, decapod crustaceans have not been favoured for research on development. The powerful molecular tools of genetics and evo-devo would surely illuminate the patterns of evolutionary change in the escape circuit and provide strong evidence for questions such as whether the G. strigosa MoGH is truly homologous to the crayfish MoG. Thus, a major goal for crustacean neurobiologists should be to bring modern molecular tools to bear much more forcefully.

It's those two sentences -- sentence and a half, really -- that lead me into Marmorkrebs research. I thought that understanding the development of the giant neurons would be very interesting and informative about the variation of the neural circuit across different crustacean species. And when I started to think about how I might get my hands on a lot of embryos, it seemed that Marmorkrebs had the greatest potential to be an organism that would allow me to study neural development.

That was how I got into this game. I got my first Marmorkrebs later that year.

And a lot more people should read my article. (The title of this post is "Shameless self-promotion," after all.)

References

Colbourne J, Singan V, Gilbert D. 2005 wFleaBase: the Daphnia genome database. BMC Bioinformatics 6: 45. doi: 10.1186/1471-2105-6-45

Faulkes Z. 2008. Turning loss into opportunity: The key deletion of an escape circuit in decapod crustaceans. Brain, Behavior and Evolution 72: 251-261. doi: 10.1159/000171488

Stumbled

I happened to check site traffic today (which I don't do all that often) and noticed that there had been a huge spike in visitors compared to the what the site normally gets. It seems to be mostly due to a review at StumbleUpon. Thanks to the reviewer for mentioning the site.

If you've stumbled here, I hope you'll check back one in a while. I hope to be adding new resources for the curious and pet owners, in addition to those for scientists, in the near future.

Blogrolling

One of the good things about the Open Laboratory competition is that you discover new blogs, of course. I was pleased to find another crustacean blog among the finalists for the Open Laboratory 2008, Dear Blue Lobster. The winning post is "Bloop: A Crustacean Phenomenon?"

I'm also tickled that he had a post about Marmorkrebs last year, which I somehow managed to miss until recently. The post includes a rumour that I have yet to confirm, namely that research is going on in China to aquaculture Marmorkrebs.

(Blue lobster picture from Photo of the month from the Lobster Institute.)

Vogt and colleagues, 2009

Vogt G, Wirkner CS & Richter S. 2009. Symmetry variation in the heart-descending artery system of the parthenogenetic marbled crayfish. Journal of Morphology: 270(2): 221-226. http://dx.doi.org/10.1002/jmor.10676

Abstract

The internal anatomy of freshwater crayfish is strictly bilaterally symmetric, with the conspicuous exception of the vertically oriented descending artery (sternal artery), which originates from the heart and terminates in the subneural artery. Serial sectioning of 133 juveniles of the parthenogenetic marbled crayfish revealed that the descending artery was bilaterally symmetric in 4.5% of the specimens, right asymmetric in 45.1%, and left asymmetric in 50.4%. In the bilaterally symmetric variant two branches arise from the left and right chambers of the bulbus of the heart, run laterally around the hindgut, and fuse underneath it. The asymmetric variants have only one dorsal branch, which loops around the hindgut on either the left or the right side. Other structures of the heart, such as the paired antennary and hepatopancreatic arteries and the ostia or the unpaired anterior and posterior aortae, showed no symmetry variation. Because of the genetic identity of the experimental animals and their culture under identical environmental conditions, the variation in symmetry of the descending artery observed is interpreted as the result of developmental variation. We recommend that the marbled crayfish be considered for investigation of the epigenetic mechanisms responsible for the maintenance and breaking of bilateral symmetry in metazoans.

Keywords: symmetry • sternal artery • heart • epigenetics • variation • development • marbled crayfish

SICB 2009 review

It was utterly appropriate that our lab's first research poster on Marmorkrebs be at the 2009 SICB meeting in Boston. Because Boston is a place that worships crustaceans.


If that is not a shrine to lobsters, I don't know what else it could be. Bow your head!

We went out to the meeting a day early with the aim of visiting some other Marmorkrebs labs in the area. We stopped off at Harvard university, and enjoyed the hospitality of post-doc Frederike Alwes, who works in Cassandra Extavour's lab on invertebrate development. Frederike rocks.

The doors on the Harvard Biology building again showed evidence of crustacean worship:


(In fairness, many other organisms were present on the doors and on the walls of the building.)

The SICB meeting itself was a packed to the rafters. I heard reports that attendance was around 1,800, and that this was about 50% more than last year!

Be that as it may, the poster session went well. We introduced many individuals to Marmorkrebs for the first time, and my co-author and poster presenter, Stephanie, had many interesting conversations.


We had hoped to make it to Barb Beltz's lab sometime during the trip. Unfortunately, first scheduling and then the weather conspired against us. We had a very small window of opportunity spoiled by the prospect of an ice storm. Having lived through the massive Montreal ice storm of 1998, I wanted no part of that. Others may brave the Massachusetts cold in the name of science.... but let's just say my students insisted taking a cab instead of walking to the nearby subway station when we left.

Luckily, there wasn't an ice storm that morning, but the rain on the window indicated it could very easily have been otherwise.


If you're one of the individuals who met us at SICB and are visiting the website for the first time, welcome! We hope you continue to visit, and hope we can provide resources for you. It looks very likely that we will be able to do so, as several more of our animals went into berry for the first time in the five days we were gone.

Thinking about the law

The question of legality of buying and selling Marmorkrebs crops up again here. I mused a bit about this before, but don't have more to say yet.

Note to myself: I really must work up a FAQ...

Another case of mistaken identity

Marble Crayfish (?)
Originally uploaded by aeschylus18917

When Marmorkrebs shows up as a Flickr tag, I pay attention. The comments for this picture, though, correctly point out that this is certainly a case of mistaken identity.

Though how that crayfish got to be over 20 cm is a puzzle...

Open Laboratory 2008

Just a quick one before I hit the hay after a wonderful full frantic day at the SICB meeting... A post from this blog, "How Marmorkrebs can make the words a better place," was selected as a finalist for the Open Laboratory 2008.

Put a little love in your heart.