The special session on crayfish biology at SICB may well have been one of the busiest days for Marmorkrebs news and announcements in a long while. There were at least three major pieces of new information about our favourite crustacean.
Peer Martin provided evidence that Marmorkrebs are triploid. This is an important step forward in understanding the original of asexual reproduction in this species. This strongly suggests that this may have been a "one off" chance event, either through some sort of incomplete separation of chromosomes or duplication of chromosomes, or hybridization.
As part of Peer Martin's talk, he discussed whether Marmorkrebs are "the perfect invader" as they were so memorably called. He included a discussion about the importance of crayfish plague as an issue in the invasive potential for Marmorkrebs. In the questions, I asked whether anyone had actually tested whether Marmorkrebs carry the plague, or whether it was simply assumed they were resistance, because essentially all North American species are. There is apparently one doctoral thesis that reports a Marmorkrebs carrying crayfish plague. That said, many in the lab, and one wild-caught animal, have tested for the disease.
More introductions in the wild
Chris Chucholl reported that there are now six confirmed populations in Europe, five of which are in Germany. During my talk, I reported the "breaking news bulletin" that I'd blogged while waiting in line at Starbuck's for a croissant that Marmorkrebs had been found in Sweden. Tadashi Kawai mentioned that a population had been found in Sapporo, but that it apparently died out.
Marmorkrebs was not the only only game in town in this session, however.
Tonio Garza de YTa discussed his experiences over a decade in working with farmers to develop sustainable, productive, profitable aquaculture for red-clawed crayfish in Mexico. The lessons he had were to develop the market first. There is no point in producing food nobody will buy. Secondly, make sure your product does not give itself away. The red-clawed crayfish got away from their cultured ponds and successfully established populations, which could be harvested more cheaply than the aquacultured crayfish.
Francesca Gherhardi talked about the importance of understanding behaviour of potentially invasive species. To give just one example, she examined the interaction between temperature and fighting between different invasive crayfish species. Spinycheek crayfish (Orconectes limosus) become more less active and more likely to seek shelter as temperatures increase. Signal crayfish (Pacifastacus leniusculus) become less competitive as water warms. Red swamp crayfish (Procambarus clarkii) change their aggressive behaviour very little, meaning swamp crayfish are poised to be the winners as temperatures warm under climate change.
Incidentally, my sympathy goes to Francesca, who was having quite severe voice problems. She had to whisper her whole talk. This worked to her advantage, as it gave her presentation an urgent, conspiratorial tone
Keith Crandall talked somewhat about some new research he is co-authoring on crayfish relationships, but much of his talk was geared to discussing tree of life projects. In particular, I’m excited about opentreeoflife.org. Most taxonomic papers now are published as PDFs, which are great to look at, but hard to re-use any data in them.
The goals of the Open Tree of Life project are, in part, things near and dear to much of the online science community. They want to encourage refinement of the tree, annotation, and promote a culture of data sharing, not simply publication. Currently, people are as consistent about putting things into Treebase or Dryad as they are into GenBank.
Oh yes, and they want to assemble a complete tree of life in three years. Keith mentioned that the National Science Foundation has been supporting various tree of life related projects for about a decade now, and are getting quite eager to see a tree. This project will make it easier to identify holes in the existing tree.
A great session marred only by the fact that I had to run to catch my plane, and couldn’t stay and chat more with the other speakers! Much thanks to Tadashi Kawai for organizing the session!