28 December 2011

2011 was not the best year ever for Marmorkrebs research

If last year could be seen as a breakout year for Marmorkrebs research, this one might be counted as a correction.

As anyone who’s studied statistics should know, an extraordinary event is more likely to be followed by a rather more ordinary one. I am hoping this is just a temporary dip for Marmorkrebs research, and that in 2012, the upward trend will resume. And on a personal note, I look forward to carrying out the research funded by #SciFund in 2012!

In the larger crustacean realm, probably one of the most noteworthy news stories of the year was the publication of the first crustacean genome. But I keep wondering every time I hear about the advances of high throughput sequencing and how cheap and easy it’s getting... why don’t I have a crayfish genome yet? Grumble grumble grumble.

20 December 2011

New Freshwater Crayfish

I got the hardcopy of the newest issue of Freshwater Crayfish last week. It’s the first part of volume 18. The production values are good, with sharp figure reproductions and gloss paper. There are some colour figures, too!

As I mentioned previously, the society International Association of Astacology really wants to have a push to get the journal published much more regularly. It used to be published only in alternate years. The society hopes that this will allow Freshwater Crayfish to be indexed in services like ISI Web of Science, which would mean that the journal could get an official Impact Factor.

Manuscripts for Freshwater Crayfish are now being accepted continually. The turnaround time from submission to publication should be on the order of months, rather than years. Submissions can uploaded to: http://iz.carnegiemnh.org/FCEditor/

Disclosure: I have an article in this issue, though not on Marmorkrebs.

Hippler and colleagues, 2011

Hippler D, Hu N, Steiner M, Scholtz G, Franz G. 2011. Experimental mineralization of crustacean eggs leads to surprising tissue conservation: new implications for the fossilization of Precambrian-Cambrian embryos. Biogeosciences Discussions 8: 12051-12077. http://dx.doi.org/10.5194/bgd-8-12051-2011


Phosphatized globular microfossils from the Ediacaran and Lower Cambrian of South China represent an impressive record of early animal evolution and development, however their affinity based on putative embryonic metazoan, bacterial and inorganic features is strongly debated. Understanding key processes and conditions that cause exceptional egg and embryo preservation and fossilization are therefore crucial for a reliable interpretation of their phylogenetic position. Taphonomic experiments on eggs of the marbled crayfish indicate a close link between early mineralization and rapid anaerobic decay of the endochorional envelope, producing different preservational stages of degradation resembling the various decay stages observed in the fossil record. Stabilization of the spherical morphology was achieved by pre-heating of the eggs. Complete surface mineralization occurred under reduced conditions within one to two weeks, with fine-grained brushite (CaHPO4·2H2O) over calcite as the dominating mineral phase. Although the endochorional envelope was not preserved, experiments resulted in exceptional preservation of the embryonic tissue at the cellular level. Thus our findings suggest that the mechanisms of decay, preservation of surface structures, and mineral replacement in the experiment and during fossilization of Cambrian embryos were likely operating at a similar rationale.

Keywords: None provided.

Note: This discussion paper is under review for the journal Biogeosciences. This journal has an editorial policy that differs from many other journals, described as “innovative two-stage publication process with Public Peer-Review & Interactive Public Discussion.” The paper is initially published – permanently archived – in Biogeosciences Discussions, to receive comments (which are also archived). If the paper is accepted by the editors of Biogeosciences, the final version appears in that journal as the “copy of record.” If not, the paper remains in Biogeosciences Discussions, does not contribute to the Biogeosciences’ Impact Factor, etc.

15 December 2011


And there’s the siren! The #SciFund challenge has came to an end! Here are some of my initial reactions to the experience.

Things that I didn’t expect:

Fewer people, bigger donations. I thought most donations would be small – a dollar or two – and projects would have hundreds of supporters. Instead, projects had tens of supporters contributing $10-20, and more, often much more. Consequently,  my “I make my target if everyone chips in 50 cents” pitch to my several thousand followers on Twitter and Google Plus wasn’t effective.

Traditional media still rules. The break out success story was, without a doubt, Kristina Kilgrove’s Roman DNA project. There’s no doubt that it made it because it was on the CNN website.

Cool beats practical: Given how much talk there is on how people want to see “results” and “return on investment” in traditional funding, my one post where I described how my research might have a practical pay-off to aquaculture got the least hits of anything I did to promote my project over six weeks.

Weak relationship between video views and dollars. “Duck force” got more than ten times the views of my video, but it didn’t get ten times the donations.

Front end loaded: I expected most funds to come in at the very beginning and the very end. RocketHub confirmed that this is the normal pattern. But the “bump” in the last few days was much smaller than I expected. On my project, the amount of dollars raised and time elapsed were pretty tightly correlated.

So emotional: I touched on this before here. I got way more wrapped up in this tiny little fundraising effort than most other projects.

Not much variation. Most projects raised about the same amount, regardless of their targets. $1,000 or so seems to be the sweet spot for now.

I made the right call to keep my project target small. At one point, I almost raised it, and if I had, I don’t think I would have made it. Projects that want to raise ten grand are either going to have to be brilliant or wait for the crowdfunding of science to mature.

Things that disappointed me:

Notice us! We didn’t get as much attention from science media as I expected. No coverage in the Science, Nature, The Guardian, The New York Times, Quirks and Quarks, and so on.

Whiff: Thirty-nine projects didn’t meet their targets.

Low gear: I was hoping to be one of the first projects to get past the post. I though that I would have a good shot at it, based on responses of people to whom I showed my video, and that I had one of the lowest targets.

Left undone: I had ideas for three more videos that I didn’t get to make.

Things that made me happy:

Mad skills: I learned a lot about how to make short videos. I may be doing more.

Total: Over $75,000 for science!

Hits! Ten projects met their targets.

This time, it’s personal: And one of them was mine.

If #SciFund were to go again:

I would say: Yes. Even though it’s inefficient, it’s fun. And as I noted, I’m unlikely to walk away completely empty-handed, which is usually what I get for writing big grant applications.

Stay home: I would try not to go to the biggest scientific meeting in the world for a week. I felt I lost quite a bit of momentum because of that.

More focus: Not my call, but at first we had over 200 people express interest in doing this. We ended up with 49 live projects. I wonder if even that was spreading attention too thin.

There will be much more analysis of the #SciFund challenge in the days and months to come. It was a social experiment, and we are all scientists, after all. But for now, this is...

Photo by viking_79 on Flickr; used under a Creative Commons license.

10 December 2011

A #SciFund success story!

We. have. MADE IT!

I was sitting at home, working on just one last video to try to convince people to support my #SciFund project, when I heard the sound of an email alert. When I saw it was from RocketHub, I was excited, because I had been getting close to my target. How much closer might I get?

When I read the email, I almost had a heart attack. It was enough to push me past the finish line!

My day went from this:

To this:

(Since I was sitting at a computer, of course my first move was to tweet about it.)

The #SciFund challenge isn’t over! I still want to see if I can squeeze out one more video promoting my project. We are allowed to have donations exceed the target. If there is enough money, I will take a student with me on the expedition! And RocketHub even rewards people who fuel a project after it hits its target with the Supernova badge!

And for those who watched my promo video all the way to the end, you’ll know I have another project  I promised to reveal if I met my target:

The Beach of the Goliath Crabs!

I will be revealing the secret of this project soon!

Thank you to those who have supported this project, either financially or morally!

(Crossposted from NeuroDojo.)

06 December 2011

Shen and colleagues, 2011

Shen H, Braband A, Scholtz G. 2011. Mitogenomic analysis of decapod phylogeny. Zitteliana B30: 46. http://epub.ub.uni-muenchen.de/12441/1/zitteliana_2011_b30.pdf (Conference abstract only)


For comprehensive study of decapod phylogeny on mitochondrial genome level, we completely sequenced 13 decapods. Together with available 32 decapods from GenBank, the datasets now covered all major decapod taxa. From the sequence aspect, Maximum likelihood (ML) and Bayesian inference (BI) of nucleotide, genome and amino acid datasets revealed similar topologies at the higher level relationships: Brachyura,Anomala), Thalassinida), Astacidea), Achelata), Stenopodidea), Caridea), Dendrobranchiata). Only Polychelida received two different positions: the basal branch of Reptantia in ML analysis of amino acid data and the sister group of Astacidea in the resting analyses. On the family level, Thalassinida is paraphyletic, which is consistent with some morphological and some recent molecular results (e.g. de Saint Laurent 1973, Tsang et al. 2008), other taxa are monophyletic. These major results confirm some of the traditional morphological views. In the gene arrangements aspect, two notable features in astacid mitogenomes evolution have been observed: a huge inversion happened in Procambarus fallax f. virginalis, Homarus gammarus and one priapulid Priapulus caudatus is supposed to be of convergent nature within the Ecdysozoa; complete loss of protein coding gene nad2 in H. gammarus and partial loss in Enoplometopus occidentalis are supposed to be synapomorphic character for Nephropidae. Additionally, a new gene rearrangement model – “invertion triggered duplication” model is also proposed according to decapod gene rearrangements. Anyhow, the mitogenomes show a good potential to resolve the relationship within Decapoda.

Keywords: None provided.

01 December 2011

Kitten or crayfish?

We’re into the last two weeks of the #SciFund challenge! And I’m getting just a little punch drunk out here...

And so, I prove yet again that everything on the Internet eventually turns to pictures of cats.

For those who have supported me already: Thank you once again!

For everyone else: Hey, isn’t it payday today? Would you miss a couple of bucks? Even a few bucks will help me meet my target!

You should visit RocketHub and support crayfish research!

29 November 2011

“The mouse model”, which I prefer to call “mice”

Daniel Engber has a mammoth set of articles on Slate on the astonishing amount of research done on mice, and the creation of the predominant model organism for all biomedical research, possibly for all of biology.

It’s a epic trilogy on the creation of the model organism, and just how far you can take that research if your goal is to cure human diseases.

  • The mouse trap: “The modern lab mouse is one of the most glorious products of industrial biomedicine. Yet this powerful tool might have reached the limit of its utility. What if it's taught us all it can?”
  • The trouble with Black-6: “In truth, the armadillos, prairie voles, and the other exotic models live only at the margins of biomedicine.”
  • The anti-mouse: “Still, slow science may have rich rewards, and the decisions we make today—on whether to invest in new model organisms or build out the ones we already have—are sure to have profound effects on the (human) generations to come.”

And a bonus coda:

Lengthy, but widely-praised – and rightfully so. Excellent investigative science journalism.

24 November 2011

The #SciFund team-up!

One of the things I love about being in the #SciFund challenge?


The advantage of #SciFund is that nobody is going it alone. We have been able to share ideas and bounce ideas around between each other, and have stronger projects and more visibility than if any one of us was trying this on our own.

In that spirit, let me introduce fellow #SciFund challenger, Marisa Tellez!

P.S.—I’m stupidly happy with how this came out.

23 November 2011

The #SciFund challenge: Half-way

Three weeks down; three weeks to go.

We’re at the halfway point in the #SciFund challenge, and my project is 51% funded. I’m on target to meet my funding goal, so I’m cautiously optimistic.

What has it all been like so far?

I’m a raging inferno of emotions here.

The moments when you see the Rocketbut email coming in announcing, “Your project has been fueled!” are great big highs – the amount does not matter. It’s just knowing that someone cared enough to help, and that you’re moving towards the goal, that make each one of those emails sweet.

But when the days go by with no emails... it’s pretty damn depressing.

Even when I know that most of the action is going to happen in the first and last weeks, and I know that it’s going to be hard to maintain momentum in the middle of the campaign (that is to say, right now), that intellectual knowledge doesn’t stop me from moping a bit when a day goes without the needle on the gauge budging.

And the media coverage is also encouraging. There’s been so much that I just haven’t been able to keep track of it all (but fortunately, there’s a compilation here). But it’s almost as encouraging to read something like this in Forbes as it is to see a donation:

My son and I watched the Indiana Jones-like video from scientist, Zen Faulkes, and thought, “we should ‘fuel’ this project.”

Why, yes. Yes, you should. ;)

I was also interviewed by Jennifer Welsh for her LiveScience article, which has been reprinted and reproduced on several other sites.

My project also gets an mention in the Daily Mail article on SciFund. I’m a bit... miffed, I suppose, that they are characterising all the #SciFund projects as “wacky,” when we are all bona fide scientists with serious projects.

Also, I wanted to point out a discussion that happened on Google Plus about trusting the #SciFund participants with your donations, and how you know those dollars make a difference.

The highs are higher, and the lows are lower, than I ever expected. I just cannot maintain the same detached, “We’ll see how it goes” attitude that I take with normal grant submissions. There, I submit the manuscript, but have more more contact with the thing for months. Here, there’s almost daily contact, even when it’s not necessarily donations.

P.S.—I’m working on a few new things related to my project that I hope you will see before the end of the week!

Photo by ♥KatB Photography♥ on Flickr; used under a Creative Commons license.

22 November 2011

The curious case of crustacean colours

From time to time, you will see news of a lobster being caught with some unusual colour, like orange, blue, or calico. Some even become celebrities, of sorts. And within the pet trade, brightly coloured variations of crayfish (typically bright blue) are widely prized.

ResearchBlogging.orgWhat determines colour in crustaceans generally? It’s a complicated mix.

The most dramatic colour variants are caused by genetics. In crayfish, several colour morphs are due to simple recessive genes (Black and Huner 1980), of the sort you learned about in high school biology.

Marmorkrebs are genetically identical, but they are not physically identical, and this extends to their colour. The article about them in Tropical Fish Hobbyist mentions the variation that you can get in the colour. Since these differences cannot be genetic, they must be environmental.

Bowman investigated this in crayfish decades ago by placing crayfish in normal tanks, tanks painted black, and tanks painted white. Crayfish placed in black tanks had more red colouration, and those in the white tanks, more white colouration. Bowman also noted that animals that had become adapted to the bright white tanks did not darken up again after being placed into black surroundings. There are limits to how flexible the colour changes are.

Similar changes in colour have been seen with hippid sand crabs (Bauchau and Passelecq-Gérìn 1987; Wenner 1972). These crabs are diggers, and those that live in dark beaches of volcanic sand tend to have darker carapace colours, while those living in white beaches of coral sand are lighter. If they are switched to different colours of sand, they can slowly change their carapace colour for a better match.

Why might there be variation in colours from Marmorkrebs in the same tank? Even within the same tank, small crayfish are unlikely to have the same light and food. Crayfish do fight and establish dominance, so some individuals may be consistently getting the prime locations in the tank and first crack at food.


Bauchau AG, Passelecq-Gérìn E. 1987. Morphological color changes in anomuran decapods of the genus Hippa. Indo-Malayan Zoology 4(1): 135-144.

Black JB, Huner JV. 1980. Genetics of the red swamp crawfish, Procambarus clarkii (Girard): state-of-the-art. Proceedings of the World Mariculture Society 11(1-4): 535-543. http://dx.doi.org/10.1111/j.1749-7345.1980.tb00147.x

Bowman TE. 1942. Morphological color change in the crayfish. The American Naturalist 76(764): 332-336. http://www.jstor.org/stable/2457208

Wenner AM. 1972. Incremental color change in an anomuran decapod Hippa pacifica Dana. Pacific Science 26: 346-353.

Additional: See this post on why colours change when a crustacean is cooked.

21 November 2011

Selling invaders

Myrmecos has a post looking at the online sale of exotic, and invasive, ant species. His take is simple:

This store needs to be shut down NOW.

I don’t know why anyone would have an ant as a “pet,” but regardless... Regardless of what you consider a pet, be responsible.

01 November 2011

The #SciFund Challenge launches!

The wait is over.

The final version of Doctor Zen and the Amazon Crayfish Civilization is now ready for viewing at RocketHub! If you have three minutes, you have more than enough time to learn about my project in the #SciFund Challenge!

Why can’t you watch the video here? Because I want you to go to RocketHub, and not only watch mine, but look at the other insanely cool projects that have come in from around the world. If you don’t want to support me, please consider supporting someone else.

The #SciFund Challenge is an experiment in funding science. Over the next six weeks, I will be asking for your help in raising money for a research project. I’ll be talking more about the whys and wherefores in the next few days.

Want to learn more? Or perhaps even... donate?

You should go to RocketHub right now!

25 October 2011

Celebrate diversity: Absent fathers might not be missing fathers

ResearchBlogging.orgThat you don’t see males around when a female gives birth or lays eggs doesn’t mean that a male wasn’t involved. Females of many species can store sperm for long periods, sometimes their entire lives. Queen honeybees, for instance, go on a single “nuptial flight”, and the the sperm they gain on that flight is enough for the rest of her life, which can be several years.

A rattlesnake (Crotalus adamanteus) is making the news with this point. A female that had been isolated for five years recently had nineteen little snakes. After having been alone for so long, parthenogenesis seemed a possible candidate to explain the happy occasion.

Not so. Genetic tests showed the offspring had genes from another animal besides momma, so this female had mated at some time in the past. How far back? Not known.

All of this means that determining parthenogenesis is trickier than it first appears.

Crayfish can also store sperm (Albaugh 1973), but how long is the upper limit? I’m not sure. So pet owners, just because the lone crayfish you got a while ago had babies doesn’t mean it’s a Marmorkrebs or is reproducing asexually. It may have just been biding its time.


Albaugh DW. 1973. A case of long-term sperm retention by a female crayfish (Decapoda, Astacidae). The Southwestern Naturalist 18: 97-98.

Booth W, Schuett GW. 2011. Molecular genetic evidence for alternative reproductive strategies in North American pitvipers (Serpentes, Viperidae): long-term sperm storage and facultative parthenogenesis. Biological Journal of the Linnean Society: In press. http://dx.doi.org/10.1111/j.1095-8312.2011.01782.x

Photo by OZinOH on Flickr; used under a Creative Commons license.

21 October 2011

Coming soon...

20 October 2011

Tracking your colony: SAPling

Where was this when I started my Marmorkrebs colony?

A new article in The Journal of Experimental Biology describes a software package called SAPling that is intended to track the pedigree of entire colonies of asexually reproducing animals. You can find the software at: http://genomics.princeton.edu/schoetzlab/software.html.

I’ve downloaded the software, which is written in Java. I have not quite figured out how to run the program yet, though. There’s no standard *.exe file to run. If anyone knows how to get Java *.class files going, I would be most appreciative of any pointers!


Thomas MA, Schötz E-M. 2011. SAPling: a Scan-Add-Print barcoding database system to label and track asexual organisms. The Journal of Experimental Biology 214(21): 3518-3523. DOI: 10.1242/jeb.059048

04 October 2011

Going small without going home

Over at the SciFund Challenge blog, I have a guest post about how the current grant proposal system strongly pressures scientists to ask for lots of money, even if the project doesn’t need it.

Big science is a wonderful thing. But we need new ways to fund small science. There are many projects where a few bucks here and there will grease a lot of wheels. We shouldn’t have to have the same level of difficulty in getting, and spending, small pots of money as the big pools of money.

I will be promoting Marmorkrebs research as part of this crowdfuning challenge in November. It will be fun!

22 September 2011

The SciFund Challenge

I’ve been very pleased that non-scientists have been good enough to support Marmorkrebs.org projects in the past with a bit of their time. The contributions of pet owners have been featured in two papers from my lab to date.

In that spirit, I will be participating in the SciFund Challenge! This is an experiment in social networking and crowdfunding. In November and December, participating scientists will try to raise a small amount of money for a research project. This will be conducted in association with Rockethub.

I will have more details as we get closer to the official launch of the project. In the meantime, check out the SciFund blog for more news and explanations for the rationale behind this project.


Faulkes Z. 2010. The spread of the parthenogenetic marbled crayfish, Marmorkrebs (Procambarus sp.), in the North American pet trade. Aquatic Invasions 5(4): 447-450. http://dx.doi.org/10.3391/ai.2010.5.4.16

Jimenez SA, Faulkes Z. 2010. Establishment and care of a laboratory colony of parthenogenetic marbled crayfish, Marmorkrebs. Invertebrate Rearing 1(1): 10-18. http://inverts.info/content/establishment-and-care-laboratory-colony-parthenogenetic-marbled-crayfish-marmorkrebs

16 September 2011

Being a fish out of water

It might be tricky to keep mangrove rivulus in your typical aquarium. Mangrove rivulus are rather found of jumping out of water – and staying there.

Being out of water is a rather different place from being in the water, and so this fish obviously have some evolutionary adaptations that allow it to pull off this stunt. But a new paper asks a different, possibly more subtle: do mangrove rivulus adapt to being in or out of water in the short term?

ResearchBlogging.orgMangrove rivulus have an advantage for studying these sorts of short-term physiological changes, as many of them are genetically identical, because they are hermaphrodites - not all that unusual among animals, but that they are self-fertilizing hermaphrodites is a rare and exceptional feature among vertebrates.

Turko and colleagues first did a simple correlative study, allowing the fish to jump out of their tanks as often as they want. Most stayed in the water most  of the time, but a few appeared to have what would have been a death wish in most other fish: they were out of the water almost two thirds of the time (64%). The authors saw differences in the gill shape that were correlated with the amount of time fish spent in or out of water.

But because correlation does not mean causation, the authors sensibly went back and did an experiment. They monitored animals for a week, then prevented them all from leaving the water, sacrificed half to check on their gills, and then left the remaining half go back to being free to leave the water if they chose.

The first that were prevented from leaving the water had different gill shapes than those that were allowed to return to the air. This strong suggests that the fishes’ behaviour drove the changes in the gill morphology.

But there is a problem in interpretation here. At the start of the second experiment, the fish were leaving water rather less than in the first correlation study. And there were no correlations between gill shape and the fish’s behaviour after the first week, as there was in the first study. The differences in gill shape emerged only after the week were the fish were forced to stay within water. The researchers suggest that there may be a minimum time the fish have to spend out of water for the gill remodeling effect to occur.

This makes me wonder if there were be a way to do the experiment were fish were forced to stay out of water for set periods of time. Here, the experimenters were at the mercy of the fish voluntarily leaving the water. It may be a little bit trickier, but the results would be much easier to interpret.

Related posts

Conquest of the land, a la Chubby Checker (on NeuroDojo)
Celebrate diversity: The fish that fertilizes itself


Turko A, Earley R, Wright P. 2011. Behaviour drives morphology: voluntary emersion patterns shape gill structure in genetically identical mangrove rivulus. Animal Behaviour 82(1): 39-47. DOI: 10.1016/j.anbehav.2011.03.001

06 September 2011

Molting in a nightclub

AT least, molting in a nightclub is the best explanation I have at hand for the soundtrack on this video.

30 August 2011

Crayfish kryptonite

When I talked on Dr. Kiki’s Science Hour last week about Marmorkrebs, Kirsten asked me at one point, “What’s their kryptonite?”

On the show, thinking on my feet, I said that Marmorkrebs might have some competitive disadvantages because they are a small species, and size is a very important factor in crayfish competition when animals are in one-on-one interactions. (When you match individuals for size, Marmorkrebs hold their own, however).

This is a similar question to the one I fielded at the Ecological Society of America meeting a few weeks ago. One crayfish get loose in a watershed, there is not much that you can do.

In a bit of l’esprit d’escalier, I might have added in my reply to Kiki that the kryptonite of marbled crayfish might be their reliance on humans. In general, crayfish are not all that mobile. Yes, some species are comfortable with leaving the water and making a portage to a new home, but in general, they will spread from one watershed to another only fairly slowly. They are horrible once they get established, but they have a hard time getting that first toehold without humans moving them around.

Left to their own devices, Marmorkrebs never would have made it to Madagascar, or Japan, or anywhere else. In North America, Marmorkrebs are human captives. Let’s keep it that way.

26 August 2011

Dr. Kiki’s Science Hour

This week, I had a lovely live chat with Dr. Kirsten Sanford, a.k.a. Dr. Kiki on Dr. Kiki’s Science Hour! She titled Episode 110, “Invasion of the Marmorkrebs!”

You can listen to the audio, as well as subscribe to the show’s audio and video feeds, here.

Additional: And the video is now up on iTunes, YouTube, and elsewhere!

16 August 2011

Celebrate diversity: Stingrays

This news story is a good example of the surprises animal keeping throws up:

Sea Life London Aquarium staff were shocked to discover two female stingrays were pregnant, despite that they have had no male contact for two years. ...

It is not unknown for rays to store sperm and wait until “they decide the timing is right” before they give birth, head curator at the central London attraction Paul Hale said.

Could it be parthenogenesis? A quick peek in Google Scholar reveals no records of parthenogenesis in the group. Stingrays’ cousins, sharks, can reproduce without sex, however (previously covered here). That means it is at least plausible to be parthenogenesis rather than sperm storage.

Somebody better be collecting DNA from all those baby stingrays to test this!

At any rate, this story does give me an excuse to watch this:

Hat tip to David Shiffman. Photo by by TGIGreeny on Flickr, used under a Creative Commons license.

An Achilles’ heel?

ResearchBlogging.orgLast week, at my Ecological Society of America talk, one of the questions asked afterwards was, “Could the fact that Marmorkrebs are genetically identical be exploited to control introduced, unwanted populations?”

I said, “No.”

One of the things I admire about crayfish is that they are tough little survivors. Unfortunately, this means that they are hard to get a handle on once they’re loose.

I think it’s fair to say that the weapons used to control crayfish populations are blunt instruments. There have been culls to lower the numbers. Dams to try to stop the spread (Dana et al., 2011). And an approach that might be best summarized by this famous quote by Sigourney Weaver:

Peay and colleagues (2006) have conducted a number of trials with broad applications of biocides. These are the freshwater equivalent of nuking everything from orbit. Their results have been variable at best in eliminating crayfish from water bodies.

We are so far from any kind of control that targets crayfish in general that something that targets Marmorkrebs in particular is a pipe dream.


Dana ED, García-de-Lomas J, González R, Ortega F. 2011. Effectiveness of dam construction to contain the invasive crayfish Procambarus clarkii in a Mediterranean mountain stream. Ecological Engineering 37:1607-1613. http://dx.doi.org/10.1016/j.ecoleng.2011.06.014

Peay S, Hiley PD, Collen P, Martin I. 2006. Biocide treatment of ponds in Scotland to eradicate signal crayfish. Knowledge and Management of Aquatic Ecosystems 380-381: 1363-1379. http://dx.doi.org/10.1051/kmae:2006041

09 August 2011

Got recipes?

Marmorkrebs probably don't make very good eating compared to other crayfish species, as they are a rather small crayfish. But many that shouldn't stop you from checking out Invasivore.org, a site devoted to the notion that one of the best features about invasive species is the sense of retribution we can get for the harm they do to ecosystems when we eat them.

26 July 2011

Écrevisse marbrées

A new paper reviews the human uses of crayfish, and crayfish in human culture. It contains a single long paragraph about Marmorkrebs. Most of it will be familiar to readers of this blog, but I was intrigued by this section.

Particularly in France, aquariologists are very fond of this species: they propose exchanges, sell and buy through internet. They even gave to the species the (obviously erroneous) Latin name of “Procambarus marmor” with the “Procambarus marmor blue” and “Procambarus marmor cherry” as options (P. Nöel, pers. comm., 2009).

I was unaware that Marmorkrebs had a French following. Google Analytics says that French readership of this blog is behind four other European countries.


Gherardi F. 2011. Towards a sustainable human use of freshwater crayfish (Crustacea, Decapoda, Astacidea). Knowledge and Management of Aquatic Ecosystems 401:1-22. http://dx.doi.org/10.1051/kmae/2011038

19 July 2011

The Irish have been lucky so far

The Irish Times has a column describing the threats to the native white-clawed crayfish from the cast-off pets. It describes Marmorkrebs in detail that is surprising, considering that Marmorkrebs have never been found in Ireland:

An outstanding threat among the little “lobsters” now offered online by aquarium suppliers is the attractive marbled crayfish, or “marmorkrebs”, an aquarium-bred strain of an American crayfish species, Procambarus fallax forma virginalis. The last word conveys its particular menace. Marmorkrebs is parthenogenetic – its eggs develop without male intervention – and continuously produces young. How many crayfish does a home aquarium need before offloading into the nearest stream or pond? Like virtually all American crayfish, P fallax can carry and transmit plague, and it is already naturalised in several places in Europe.

There are a couple of notable things in this article. It’s the first time I’ve seen it given the full species name from Martin and colleagues (2010) appear in a popular article. Second, it states that Marmorkrebs carries crayfish plague as a demonstrated fact. This is extremely likely, but has never been conclusively tested, to my knowledge.

12 July 2011

Crayfish rock – and I don’t just mean crustaceans are great

There are many connections between this blog and Germany. This is not one I expected. I’m not entirely sure how a German rock band singing in English took on the name of The Crayfish, but here you have it.

No video of it, but I rather like Broken Bridge from the band’s last album, Sticky Sweet Sins. You can check out more at the band’s home page.

05 July 2011

Bad bait

On the Marmorkrebs home page, I added the following text in bold a couple of months ago:

Marmorkrebs should not be kept in outdoor tanks or ponds, used for bait, or used in any other situation where they could be released into natural ecosystems.

I was pleased to see that this piece of advice was cited in this thread on a fishing forum when someone asked if there were laws concerning the use of Marmorkrebs as bait. But it occurred to me that I should provide more information in support of the statement.

ResearchBlogging.orgThe sale of crayfish is a completely grey market, as I found trying to track down pet ownership of Marmorkrebs. Trying to gather good information about the sale of crayfish for bait is hard, and as far as I can find, Bob DiStefano and colleagues have done probably one of the only systematic studies to examine this.

DiStefano and colleagues surveyed all the American state and Canadian provincial agencies in more detail than on my page. They found that about half of the jurisdictions responding reported problems caused by crayfish used as bait. Yet of those, only a few had banned the use of crayfish as bait outright. The other states and provinces had some other legislation intended to prevent the introduction of exotic crayfish, such as limiting how far they could be transported. This tremendous hodgepodge of rules and regulations doesn’t lend itself to easy enforcement.

The team also did extensive surveys of bait shops in Missouri. Missouri is one of the jurisdictions that has a series of regulations designed to prevent the spread of crayfish across watersheds rather than an outright ban. The state is trying to do the right thing. But not surprisingly, the authors turned up a lot of illegal crayfish; in their brief surveys, 27% of the bait shops had illegal crayfish.

Some shops had legal crayfish species that were gotten by an illegal means (e.g., from out of state).

Almost none of the shop owners had a clue about what species of crayfish they had.

Even if the bait shops were following all the laws (which were few and far between), there’s no way of knowing what the fishermen they sold the bait to did.

It’s difficult to know how many introductions have been caused by a combination of careless bait shop owners and fishermen, but this paper provides some hints of past introductions that could have been cause by crayfish being released as bait. Procambarus acutus is mainly distributed in the south-eastern corner of the state, but there are pockets further north that are probably the result of bait sales.

Missouri is the only state or province so far to prohibit Marmorkrebs specifically, the chances are good that if you’re using Marmorkrebs as bait in many jurisdictions, you could easily be running afoul of some other law.

In short, using Marmorkrebs as live bait isn’t the problem; using any crayfish as live bait is a problem! About the only exception would be a crayfish you catch at the bank of the river or lake you intend to fish in.


DiStefano RJ, Litvan ME, Horner PT. 2009. The bait industry as a potential vector for alien crayfish introductions: problem recognition by fisheries agencies and a Missouri evaluation. Fisheries 34(12): 567-597. DOI: 10.1577/1548-8446-34.12.586

28 June 2011

Marmorkrebs on the road: ESA 2011

The 96th annual meeting of the Ecological Society of America is coming up in Austin, Texas in August. Relatively speaking, that’s practically in my backyard, so I’ll be there. My co-author Stephanie presented at this conference a couple of years back, but this is the first time that I’ll be going to the meeting and presenting. The abstract of the talk is here.

I’ll also be presiding over the session, Predator-Prey Interactions I. I think it only fair to warn any presenters in that session:
  • Don’t you dare go over time.
  • Don’t you dare have Comic Sans in your slides. I will name and shame on my blogs!

Please stop by and say hi!

21 June 2011

Great moments in science music: Nemesis

This song has three ties to science.

  1. It is the only song I know not only to contain the word “parthenogenesis” (a frequent topic of this blog!), but to use it in the chorus as part of the rhyming scheme.
  2. It’s about the theory that a dwarf star is responsible for periodic mass extinctions in the fossil record, and this hypothetical star was called “Nemesis”.
  3. Stephen Jay Gould mentioned it in a essay on mass extinctions. He wrote that the lyric, “You can’t imagine / how bad it gets” was a fair estimation of the song itself. Ouch.

13 June 2011

The Crustacean Society 2011: Day 4

Audiences were rather small for the sessions of the last day of The Crustacean Society meeting. It wasn’t that people had left Hawaii (though some had), but they had upped the number of scientific sessions from two to three, so audiences were split three ways instead of two.

The closing ceremony had a few noteworthy elements.

The Crustacean Society Excellence in Research Award (TCSERA) was awarded to Gerhard Scholz, which I live-blogged here.

There were two long, excellent tributes to respected crustacean scientists who recently died. The portraits were of two biologist that had several things in common: a fierce (some might say terrifying) work ethic, and unconventional career paths that did not follow the typical pathways for academics.

Patsy (Pat) McLaughlin
: The impression left here was of a woman with a strong personality, who loved her work, dogs, and husband. She hated having her picture taken, but when she warmed to a person, was unfailing generous. She was working at a time when opinionated women were not encouraged, and she had some teaching jobs, but mostly was not affiliated with universities.

L. B. Holthuis (pronounced roughly as “Holhoyce,” I learned): The man worked at his museum for over 60 years for six days a week. On Sundays, he read books. When he visited the Smithsonian Institution, he was asked why he always ate peanut butter sandwiches for lunch. He replied that it was cheap, and that way he could save up and spend more money for books.

Program director Chris Boyko gave us firm instructions before we left for the conference banquet at the Waikiki Aquarium, “Do not touch the monk seal!” (I wondered, “But what if the monk seal touches me?”)

Buses then took the scientists to the banquet, held at the Waikiki Aquarium. The aquarium is sort of a medium-sized aquarium. not as large as some I’ve seen (Monterey Bay comes to mind). Most of the exhibit focused on coral reef habitat. I particularly like a tank where they were rearing giant clams. I hadn’t remembered their lips being so colourful!

Ironically enough, the one item served that everybody hated... the shrimp! Distinctly dodgy. But nobody was showing signs of food poisoning by the time the buses went back.

The student awards were given out, and current president Akira gave president elect Christopher Tudge the official tie of the society president.

One of the things I wish people could hear would be a recording of the bus to the banquet, and the bus coming back from the banquet. After we got back to the Ala Moana hotel, people were still hanging around in the lobby, and you could tell that people were reluctant for the conversations to end.

Those carcinologists loosen up once you get a cheap glass of wine or two into them.

My flight left early Friday evening, so I had one day to much about on my own in Waikiki. Despite my blog post about digging for sand crabs, I didn’t think I would have much luck on Waikiki, and I was kind of fascinated by Diamond Head on this trip for some reason. I walked down toward Diamond Head, and was astonished to find Kanipoli Park: completely beautiful and almost entirely empty. Phenomenal views of Diamond Head. I couldn’t quite understand why people getting a tan wouldn’t do it in the park instead of the much more crowded Waikiki.

After that, I went to the Honolulu Zoo. The line was a bit intimidating at first, and I learned it was “Family Fun Day.” I stuck it out, as I couldn’t figure out what else I’d do with my afternoon, and was glad I did. It was much bigger than I expected, and very good (exception was the elephant exhibit, which is being completely redone - it needs it). I was able to walk through at a nice pace, no hurrying, and finished just minutes before my “I must leave now to make sure I get the airport shuttle” deadline.

Mahalo to:

Nikos Lessios, University of Arizona grad student who shared a room with me. Nikos saved my ass at least twice. First, he let me use his computer to make some last-minute changes to me presentation when my netbook was not up to the task of dealing with the massive monster presentation I’d created.

Second, he found me razors during a shopping trip so I could shave and not look like a bum throughout the meeting.

I’m also pleased that Nikos was the winner of the student poster competition. And he had been reading the Better Posters blog for ideas for his poster. (See? The advice over there isn’t completely crazy!)

Leslee Morehead for Marmorkrebs discussions.

All the Australians, who brought me news from friends in Melbourne and made me more determined than ever to make a triumphant return someday.

Brian Tsukimura for inviting me to the invasive species symposium.

Chris Boyko for suggesting I participate in a completely unrelated symposium to the one I ended up in.

Christie Wilcox, whose advice on places to check out in Honolulu was unerring.

Next year’s summer meeting is in Athens, Greece. And if you do any crustacean research, you should join the society!

09 June 2011


Gerhard Scholtz has just been awarded The Crustacean Society Excellence in Research Award (TCSERA)!

Dr. Scholtz was the first author on the first paper introducing Marmorkrebs to the scientific community, and other Marmorkrebs papers as well.

While Dr. Scholtz has co-authored multiple Marmorkrebs papers, it was mentioned this is just a small fraction of his scientific papers, around one hundred.

Marmorkrebs papers by Gerhard Scholtz

Scholtz G, Braband A, Tolley L, Reimann A, Mittmann B, Lukhaup C, Steuerwald F, Vogt G. 2003. Parthenogenesis in an outsider crayfish. Nature 421(6925): 806-806.

Vogt G, Tolley L, Scholtz G. 2004. Life stages and reproductive components of the Marmorkrebs (marbled crayfish), the first parthenogenetic decapod crustacean. Journal of Morphology 261(3): 286-311.

Alwes F, Scholtz G. 2006. Stages and other aspects of the embryology of the parthenogenetic Marmorkrebs (Decapoda, Reptantia, Astacida). Development Genes and Evolution 216(4): 169-184.

Braband A, Kawai T, Scholtz G. 2006. The phylogenetic position of the East Asian freshwater crayfish Cambaroides within the Northern Hemisphere Astacoidea (Crustacea, Decapoda, Astacida) based on molecular data. Journal of Zoological Systematics and Evolutionary Research 44(1): 17-24.

Martin P, Kohlmann K, Scholtz G. 2007. The parthenogenetic Marmorkrebs (marbled crayfish) produces genetically uniform offspring. Naturwissenschaften 94(10): 843-846.

Kawai T, Scholtz G, Morioka S, Ramanamandimby F, Lukhaup C, Hanamura Y. 2009. Parthenogenetic alien crayfish (Decapoda: cambaridae) spreading in Madagascar. Journal of Crustacean Biology 29(4):562-567.

Martin P, Dorn N, Kawai T, van der Heiden C, Scholtz G. 2010. The enigmatic Marmorkrebs (marbled crayfish) is the parthenogenetic form of Procambarus fallax (Hagen, 1870). Contributions to Zoology 79(3): 107-118.

Martin P, Shen H, Füller G, Scholtz G. 2010. The first record of the parthenogenetic Marmorkrebs (Decapoda, Astacida, Cambaridae) in the wild in Saxony (Germany) raises the question of its actual threat to European freshwater ecosystems. Aquatic Invasions 5(4): 397–403.

The Crustacean Society 2011: Day 3

Today was a short day at The Crustacean Society meeting. Maybe it was so everyone could celebrate World Oceans Day by going to the Waikiki beach?

The morning saw a panel titled, "The Future of Scientific Publishing." Panel members included the editors of Raffles Bulletin of Zoology, Invertebrate Systematics, Journal of Crustacean Biology, Crustaceana Monographs, and a representative from Brill, the publisher of Crustaceana.

All five panelists gave about a 5 minute blurb about changes at the journal. The common features for all of them were:

  • The adoption of going electronic for all stages of the production, though some journals are adopting this more rapidly than others.
  • Fretting about their Impact Factors. One editor mentioned that they were even receiving pressure from libraries to have a high Impact Factor.

That took up almost half the allotted time. This was somewhat unfortunate, given there were lots of questions and comments from the floor. This panel was scheduled for an hour, but could have easily gone twice that.

A little background may help place some of the particular concerns brought up in this panel in context. Many of the people publishing in these journals do taxonomy and systematics and things that often involve naming new species. Thus, they have rules set down by the International Committee on Zoological Nomenclature they have to follow. One of those rules is that a species name must appear on printed paper to be valid. This has probably been a major factor in the slow progress of some of these journals to move to electronic publishing. Shane Ahyong, editor of Raffles Bulletin of Zoology, noted that this rule was up for debate and possible revision. But that doesn't mean the rule will change.

Ahyong said that electronic publication created three main problems. While he was speaking of these particularly in the context of species names, these are obviously concerns across all academic publishing.

  • Anyone can create a journal now. There are concerns that this will mean there will be no assurance of quality control and that "chaos will reign." (Er, how ordered are things now? Not very.)
  • The long term stability of electronic formats still has to be proven. It is not clear whether PDFs will exist in, say, 2030. (The audience later got a horror story of a long gestating book that has been slowed by repeated changes in word processing formats.)
  • There is a need for texts to be completely unchangeable. People doing naming want to keep want to have a single, definitive record that cannot be altered at any point.

After that, much of the discussion revolved around speed. Speed of review. Speed of the editorial decision. Speed of publication after acceptance. One editor noted that people used to wait a year from acceptance to publication, but that nobody would stand for that now.

Crustacean Society program officer Chris Boyko asked if this emphasis on speed meant that it was possible for a paper to have a decision too rapidly. I mentioned that I didn't want my paper rejected in eight minutes. (Much laughter to this anecdote.) Chris's implication was that a good paper and good review couldn't be knocked out in a few days.

At this point, a graduate student expressed her dislike of PLoS ONE. She said that in her experience, about half the papers in the journal were poor. This surprised me, and I wasn't sure what she meant. I brought up papers like the arsenic life (Wolfe-Simon et al. in Science) and kin selection (Nowak et al. in Nature) which had people saying, "These are flawed and should not have been published." I thought she might have meant PLoS ONE papers were small or trite, but she said she thought many were not well done on the experimental design end. She apparently thought that there needed to be much stronger filtering and quality control.

Fred Schram, the editor of The Journal of Crustacean Biology, had perhaps an unusual take on the matter. He said, "Don't blame the journal for a bad paper. Don't blame the editor for a bad paper. Don't blame the reviewers for a bad paper. Blame the authors for having the temerity to put up bad research for publication." (This brought some applause from the audience.) Ultimately, he emphasized, the authors have to take full responsibility for the material. (Of course, this does raise the question of what value reviewers and editors are adding to the process.)

Open access did, of course, come up, but closer to the end of the session, and didn't get perhaps the airing it deserved. The Brill representative said (which I predicted he would say) that open access articles are downloaded more often, but not cited more. Ahyong said he didn't have any hard data, but did note that his journal’s impact factor started going up around the time the journal went to open access.

Related to open access were questions about costs. An audience member asked, “Where does all the money for journals go?” Fred Schram replied that it would take an afternoon to discuss this. (Another indication, perhaps, that the panel session was too short.) The representative from Brill claimed that the average cost to publish a single scientific article was costs $3,000. This included costs of servers, production staff, and the like. He also pointed out that “for profit” does not mean “no open access.”

This was not a bad panel, but I did not feel I got the glimpse into the future of scientific publishing that the session’s title advertised. It may be that journals in this field are moving particularly slow, because they is being held back somewhat by the rules on species naming. There are bolder, more innovative ideas out there.

08 June 2011

The Crustacean Society 2011: Day 2

Busy day today.

Started off with a featured talk by James Carleton on invasive marine species, who talked a lot about the impact of centuries of human shipping, which means there are probably huge numbers of things that are called "native" that were brought in by humans before anyone noticed.

My talk on Marmorkrebs as an invasive species was the second talk of the entire conference. I think it went well, and got some positive feedback. I officially launched the Craywatch project during my talk, and have already got some good feedback from people who are organizing similar "watch" kinds of online resources for invasive species.

I also tried to argue that society members and the society needed to be much more active online and in social media. And to put my money where my mouth is, I announced that I had a gift for the society: a new easy to remember URL for the website:


I continued to hang out in the invasive species symposium, which featured a lot of crab invaders. There was even some good news with invasive species that were getting beaten back. Not eradicated, but at least not getting worse.

The poster session was frantic. I had three posters to present, and I was talking non-stop throughout. Although I had multiple poster, I feel like these small conferences never have enough time for poster viewing and presenting. I was the last one to leave the poster session.

No pictures today, because I somehow managed to forget to put a memory card back into my camera. The camera took some pictures on the internal memory, but I need a cable for the camera. This was my talk warm-up music:

07 June 2011

Vogt, 2011

Vogt G. 2011. Marmorkrebs: natural crayfish clone as emerging model for various biological disciplines. Journal of Biosciences 36(2): 377-382.

Without abstract. These are the section headings of the paper:

  1. What is the Marmorkrebs?
  2. How do marbled crayfish reproduce and develop?
  3. Is it true that the first juvenile stages are secured by a safety line?
  4. Why are marbled crayfish so attractive to researchers?
  5. How can marbled crayfish produce different phenotypes from a single genotype?
  6. Is negligible senescence in the marbled crayfish related to lifelong stem cell activity?
  7. Is it true that marbled crayfish are highly resistant to cancer?
  8. Are marbled crayfish good guys only?
  9. How can I be kept informed about ongoing research with the marbled crayfish?

Keywords: cancer • development • genotype-to-phenotype mapping • marbled crayfish • model organism • stem cells

The Crustacean Society 2011: Day 1

Do you think this audience is ready to hear a talk about clones tomorrow?

We were all instructed to wear our conference shirts for the group photo.

Tonight was just an opening reception, which included a Hawaiian blessing and some demonstrations of traditional and modern hula. It was quite lovely and very enjoyable.

06 June 2011

The Crustacean Society 2011: Preamble


This week I'm blogging from The Crustacean Society meeting in Honolulu, Hawaii! So expect a lots of crunchy biological goodness both here and at NeuroDojo. I'll also be tweeting a bit, I hope, using #tcs11 as the hashtag.

But now, time to find some breakfast.

31 May 2011

Another (occasionally) parthenogenetic crayfish

ResearchBlogging.orgI not sure how to describe the sound I made when I saw the title of this paper, but it was not a quiet sound. I immediately thought, “This is huge.”

A new paper in PLoS ONE reports that spinycheek crayfish (Orconectes limosus) can reproduce by parthenogenesis. Unlike a previous report of red swamp crayfish (Procambarus clarkii) reproducing by parthenogenesis, which based its claim on similar DNA from adults and no actual observed instances of reproduction, this paper claims to have isolated females that have reproduced.

The animals were taken from the wild and reared as adults, which immediately makes one think “sperm storage.” The authors argue that the genetic similarity of the offspring rules this out. I think an obvious next step is to see if juveniles born in the lab without sex can be reared through an entire generation, and in turn produce more offspring without meeting males.

This is a bombshell. It suggests that asexual reproduction in crayfish is more common than thought, particularly when the P. clarkii paper is also hinting that they can do the same. From an evolutionary point of view, this would mean that the evolution of the completely asexual lineage of Marmorkrebs may not have been as insurmountable as it first appeared.


Buřič M, Hulák M, Kouba A, Petrusek A, Kozák P. 2011. A successful crayfish invader is capable of facultative parthenogenesis: a novel reproductive mode in decapod crustaceans. PLoS ONE 6(5): e20281. http://dx.doi.org/10.1371%2Fjournal.pone.0020281

Picture from here.