31 December 2010

Celebrate diversity: Cornucopia!

Parthenogensis and other unusual forms of reproduction were in the news a surprising amount this year. There were just enough other things to write about that I didn’t have a chance to write them up in detail. In some cases, though, others did that for me.

For instance, the peppermint shrimp (Lysmata wurdemanni) made New Scientist’s “coolest animals of 2010” list. Fiedler and colleagues have a more extensive review of the genus.

Boa constrictors are well-known, often kept as pets, and nobody suspected parthenogenesis in this species until this year! This was written up in lots of places (here, here, here) and the paper is still officially in press.

Finally, another parthenogenetic reptile made the news, not so much because it was parthenogenetic, but because of the way this new species was discovered. It was found as cuisine in Vietnam. This was written up here and here, and surely other places.

A more flattering picture of this interesting little beast is below.

2010 was the year of biodiversity. And I love how these stories show that there are still many more discoveries to be made, both in species we know, and species we have yet to describe scientifically.


Booth W, Johnson DH, Moore S, Schal C, Vargo EL. Evidence for viable, non-clonal but fatherless Boa constrictors. Biology Letters. http://dx.doi.org/10.1098/rsbl.2010.0793

Fiedler GC, Rhyne A, Segawa R, Aotsuka T, Schizas N. 2010. The evolution of euhermaphroditism in caridean shrimps: a molecular perspective of sexual systems and systematics. BMC Evolutionary Biology 10: 297. http://www.biomedcentral.com/1471-2148/10/297

Grismer JL, Grismer LL. 2010/ Who’s your mommy? Identifying maternal ancestors of asexual species of Leiolepis Cuvier, 1829 and the description of a new endemic species of asexual Leiolepis Cuvier, 1829 from Southern Vietnam. Zootaxa 2433: 47–61. http://www.mapress.com/zootaxa/2010/f/z02433p061f.pdf

Lysmata grabhami picture by Phillipe Guillaume on Flickr. Used under a Creative Commons license.

Boa photo from here.

29 December 2010

Hawaiian summer conference

I wanted to point out that the summer meeting of The Crustacean Society will be held in the stat of Hawaii next year, and that the call for abstracts is now available. I do so not because there are crayfish on Hawaii, but because it gives me an excuse to show this cool logo for the meeting:

28 December 2010

2010 was the best year ever for Marmorkrebs research

Last year, I couldn’t help but being a little disappointed that there had not been more papers on Marmorkrebs published than the year before.

That is not a problem this year.

And this isn’t even including a massive review chapter on crayfish that came out at the very end of the year, or a paper that got published in the last ten days of 2010, but has an official 2011 publication date on it (Jimenez & Faulkes 2011).

2010 was not only a bumper year for Marmorkrebs research, but may also have marked a turning point, as Marmorkrebs research started to go more into the field than the lab. The story of Marmorkrebs broke into news media as an emerging invasive species and pest on two fronts.

We also got several critical questions answered: What species is Marmorkrebs most closely related to? (Procambarus fallax.) Can it survive in the wild in northern Europe? (Oh, yes.)

I was also intrigued to see a surge in the number of open access papers published this year. The first had been just last year, but this year saw about half the papers published in open access journals.

With data for the first decade of Marmorkrebs research to play with, I am cautious about seeing an increasing trend. In the spirit of science, I’m going to make some predictions. According to a linear regression of the data, we should see 14 papers on Marmorkrebs in 2015, and 20 papers in 2020.

Of course, the increase might be exponential rather than linear. Too early to say, but it might be a bit exciting if it was.

And there are papers already in the wings for 2011.

21 December 2010

Jimenez and Faulkes, 2011

Jimenez SA, Faulkes Z. 2011. Can the parthenogenetic marbled crayfish Marmorkrebs compete with other crayfish species in fights? Journal of Ethology 29(1): 115-120. http://dx.doi.org/10.1007/s10164-010-0232-2


The parthenogenetic marbled crayfish, Marmorkrebs, has no known wild population, but has been introduced into natural ecosystems in two continents. Interactions with native crayfish, particularly through fighting, could affect the ecological impact of Marmorkrebs introductions. Marmorkrebs have been characterized anecdotally as having low levels of aggression, which could mitigate their potential to compete with native species. We isolated Marmorkrebs and Louisiana red swamp crayfish (Procambarus clarkii), then conducted size-matched intra- and interspecific pairings. Marmorkrebs were as likely to win a fight as P. clarkii, although contests between P. clarkii and Marmorkrebs were significantly faster to begin than contests between two Marmorkrebs. These results suggests that Marmorkrebs have the potential to compete with other species on the same level as P. clarkii, which is itself a highly successful introduced species around the world.

Keywords: aggression • crayfish • competition • invasive species • marbled crayfish • Marmorkrebs • Louisiana red swamp crayfish • Procambarus clarkii

14 December 2010

Pic of the moment: 14 December 2010

Having recently written a summary about the first 10 years of Marmorkrebs in science, I wanted to see how research on Marmorkrebs has changed, if it has.

I’ve used Wordle before on this blog, a neat little web application that makes word clouds from text. This time, I was a little more careful in cleaning it up and only using the abstract text, so it didn’t have strays like “http” or author names in there.

I divided the papers by the total number of abstracts rather than by year, because the pace of Marmorkrebs research is increasing.

The earliest abstracts (2003 to partway through 2008; 17 abstracts all told):

The most recent abstracts (late 2008 to now; 16 abstracts all told):

There is one clear change: “Marmorkrebs” has become the nom de choix for this crayfish. Interesting.

And here's the “snapshot” of the scientific literature on Marmorkrebs as it stands near the end of 2010, combining all 33 abstracts here on the blog:

07 December 2010


At least, Google Languages said that “Marmorkrebs Jungtiere” meant “Cancer marble kittens.”

01 December 2010

Faulkes, 2010

Aquatic Invasions logoFaulkes Z. 2010. The spread of the parthenogenetic marbled crayfish, Marmorkrebs (Procambarus sp.), in the North American pet trade. Aquatic Invasions 5(4): 447-450.


The parthenogenetic marbled crayfish Marmorkrebs was discovered in the pet trade in Europe in the 1990s. Since then, its distribution through the pet trade has spread from Europe to other continents, including North America. North American pet owners were surveyed online with the aims of trying to track when Marmorkrebs entered the North American pet trade, the ways in which it spread through the pet trade, and how widely distributed Marmorkrebs are throughout the continent. Marmorkrebs have been in the North American pet trade since at least 2004, with the number of people increasing every year. While many Marmorkrebs are sold through online sources, face-to-face personal contacts account for almost as many acquisitions. The increasing spread of Marmorkrebs through the pet trade increases the probability that Marmorkrebs will be released into North American ecosystems.

Key words: crustacean • aquaria • hobbyists

A Google Spreadsheet of the data shown in Figure 1 can be found here. Below is a Google Map version; the different colours represent years people first reported getting Marmorkrebs.

View Marmorkrebs pets in a larger map