28 February 2011

Marmorkrebs on the road: TAS 2011

There will be marbled crayfish at the 114th annual meeting of the Texas Academy of Science.

Of Friday, 4 March, in Conservation Ecology poster session 2, you will find poster #884, “The parthenogenetic marbled crayfish, Marmorkrebs, in Texas.” If you are there, please stop by the poster and meet my colleague, Dr. Paty Feria.

22 February 2011

Pic of the moment: 22 February 2011

Spotted here.

15 February 2011


When I wrote my post on the Scientific American Guest Blog, “The decade the clones came,” I was sort of fumbling around for something like this without quite realizing it:

Like the Google Earth map of Marmorkrebs introductions, this will be an ongoing project. I will update it as news becomes available. I’m also still tinkering with what level of detail to provide. Currently, I don’t think it needs to contain every research paper or blog post or tweet or YouTube video featuring Marmorkrebs. But maybe with a little tweaking, it can include those without loosing the “main events” that I’d like to emphasize.

If you have suggestions, let me know!

This Dipity timeline was inspired by Ed Yong’s stem cell research timeline, who was in turn inspired by John Rennie. If anyone out there would like to pay me, sorry. It’s all about the science, not the money.

08 February 2011

Crayfish chow

One of the big advantages of working with Marmorkrebs is that they are genetically identical. And yet, they vary (see also Vogt et al., 2008).

To make experimental results from different labs around the world more comparable, you would think that the right thing to do would be to try to standardize rearing conditions as much as possible. So I was very interested in Vogt’s comment in a recent paper that he has reared eight generations of Marmorkrebs solely on TetraWafer Mix. There are not too many animals that you can raise and breed on one single staple diet.

The eagle-eyed will notice no English on the label. As far as I can tell, this particular fish food isn’t available for sale in North America. At least, I can’t find it in Tetra’s U.S. product catalog. But it can be found in several online shops based in Europe, which will ship to North America. Shipping isn’t necessarily cheap, however.

I managed to get some of this, and have found it to be a nice addition to the lab. Given that we have many animals housed individually in an Aquatic Habitats system, the wafers are much easier to give to the animals through the top holes than other flake foods. And the crayfish seem to like it.


Vogt G. 2010. Suitability of the clonal marbled crayfish for biogerontological research: A review and perspective, with remarks on some further crustaceans. Biogerontology 11(6): 643-669. http://dx.doi.org/10.1007/s10522-010-9291-6

Vogt G, Huber M, Thiemann M, van den Boogaart G, Schmitz OJ, Schubart CD. 2008. Production of different phenotypes from the same genotype in the same environment by developmental variation. The Journal of Experimental Biology 211(4): 510-523. http://dx.doi.org/10.1242/jeb.008755

P.S.—Tetra, you’ve been in business like forever. Why is your US website so hard to navigate? Couldn’t you give us a simple search box?

03 February 2011

The first crustacean genome

I’ve argued before about the need for a crayfish genome. That’s still apparently a long way off, but today, a major new paper discusses the findings from the first crustacean genome, for Daphnia pulex. It all looks very interesting.

A nice summary is found here. A press release from the team is here. And a Q&A with Jerry LeBlanc, not a co-author but a member of a consortium who works with Daphnia, can be found here.

Additional: I particularly like Holly Bik’s answer to why this project is different from other genomes:

Daphnia represents the only ‘model’ organism where we even have a vague idea of the ecology and life-history.

More additional: Ryan Gregory comments about the size of the genome, which is often described as very large:

But Daphnia pulex does NOT have a big genome. It’s about 200Mb, slightly larger than Drosophila melanogaster, and about 1/15 the size of the human genome.

Ryan is saying that the number of rungs in the DNA ladder determines the size of the genome, not the number of genes. It’s like saying you have a large hard drive: you measure the capacity, not the number of files actually stored on it.

But even then, Daphnia only has a large number of genes for an animal: Ryan notes that rice has about a third more than the water flea.

Still more additional: Mike Bok looks at the implications for vision. Why does an animal with this small an eye need so many visual pigments?

11 February 2011 additional: There’s a comment about this with the wonderful title, “Not just another genome” in BMC Biology.

01 February 2011

15th Meeting of German-Speaking Carcinologists

No, this post is not an entry for the Oddly Specific blog. I received this email from Christoph Schubart. Knowing that I have several German readers (according to Google Analytics), I thought I should pass this along.

I would like to announce that from 7 to 10 April 2011 we will be hosting in Regensburg (southeastern Germany) the 15. Meeting of German-Speaking Carcinologists. As the name implies, it would help, if participants understand some German (even if they prefer to present and communicate in English). The official deadline for inscription is over, but I realized that I may not have reached all potentially interested colleagues, so I would like to use this platform to extend a very warm welcome to all interested colleagues on this list. Accordingly, we will extend the deadline for abstract submission until 7 February.

All necessary information (in German) can be retrieved from:


Just tell me later if there are any Marmorkrebs papers.