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Can You Help?
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| From Jules. Hi Chris I was just wondering, do you know anyone among your crayfish buddies who has carried out any sort of long term monitoring of a population of crayfish. I am particularly interessted in long lived species but any would do. Its just I am building a population model for use in developing harvesting recommendations for the malagasy species but I need some parameters from elsewhere to parametreise the model as lack sufficient data. My model could easily be adapted to refer to other crayfish species so maybe you know someone working on another species but who maybe lacks the tools for population modeling who may want to work with me? It would be great if you do Jules email: jpgj2@hermes.cam.ac.uk Conservation Biology Group Department of Zoology Downing Street Cambridge CB2 3EJ phone: 01223 331698 fax: 01223 336676 Temporary address: 70 Thoday Street, Cambridge,CB1 3AS, 01223 249104 |
| From James, Here is a “short” overview of the project I have in mind involving genetics of northern hemisphere crayfishes. Project Overview: You are probably aware of the work that Keith Crandall & I (among others) have done on the relationships among the Parastacidae (southern-hemisphere crayfishes). If not, see the web link below. Initially, the study I had in mind involved resolving relationships among the North American Cambarid genera, and I am in the process of gathering specimens and data for this project. However, I think that this project could easily be expanded to include representatives of all northern hemisphere crayfishes with the inclusion of species of Pacifastacus, Cambaroides and the European Astacids, if that is, other interested people are willing to send some tissue samples. There are several key issues that could potentially be addressed with this genetic data. Testing Hobbs’ hypotheses of North American generic level relationships and of male gonopod evolution. Resolving the relationships of Cambaroides species within the Cambaridae (or possibly the Astacidae as recent data suggests, see web link below). Resolution of species status questions for the European taxa (i.e., is the currently accepted taxonomy correct, or should additional species and genera be recognized, al la Starobogatov?). Really only testable with broad geographic sampling in Europe and Russia. With good sampling within species, we could also get a better idea of the levels of genetic variation within species, something which is still poorly understood at this point in time for many crayfish species. We may also be able to look at the evolution of the whole group and possibly the routes and modes of initial freshwater colonization events (i.e., the split between the northern and southern hemisphere crayfishes., etc.). possibly many, many other applications. Essentially, with broad sampling within a variety of different species we can address a broad range of questions ranging from population-level processes (gene flow, etc), modes of speciation, and phylogenetic relationships, something which has not really been undertaken extensively in any other group of organisms (except perhaps humans). What is Needed: What I need from interested people is a tissue sample from different species (and possibly multiple samples of the same species from different localities and/or countries, if such collections are readily obtained). This tissue sample must be FRESH and can be a single cut up leg from adult individuals, minced muscle tissue from a single (large) chela, or if the crayfish is sacrificed, some cut up abdominal muscle tissue. It is preferred that the specimens NOT be placed into ethanol, but rather I can supply 2.0 mL tubes with a special buffer in which the tissues can be placed and shipped at ambient temperatures. Voucher specimens can be placed into 85% ethanol after the tissue sample for DNA has been taken. I have found that ethanol preserved specimens are a poor source of DNA (for some reason the DNA degrades after only a short while = 2-4 weeks). Therefore, DNA yields are much greater from fresh tissues placed in the supplied buffer. If there is someone that is interested in sending some tissue samples, they can contact me by e-mail (fetznerj@carnegiemuseums.org) and I will ship the protocol and whatever tissue collection tubes and buffer they may need ASAP. The other important things that are needed along with each of the samples is good descriptive locality data (GPS coordinates would be good too, if possible), species IDs, collector information, and a 35mm or digital photo (if possible) of the live specimen (this is in lieu of a voucher specimen in 85% ethanol). Tissues Needed: Most of the species of Pacifastacus. (I have some P. l. leniusculus). All species of Cambaroides. European population samples of A. astacus, A. leptodactylus, A. torrentium, A. pallipes and other populations possibly representing Starobogatov’s Pontastacus & Caspiastacus, etc. References of possible interest: http://zoology.byu.edu/crandall_lab/docs&data/pdf_files/2000/SAcraysJCB00.pdf http://zoology.byu.edu/crandall_lab/docs&data/pdf_files/2000/Crandall_et_al_2000_cf_origin.pdf http://zoology.byu.edu/crandall_lab/fetzner/Docs/Crandall_et_al1999_AJZ.pdf Others: http://zoology.byu.edu/crandall_lab/cranlabpubs.htm Thanks again for the help! Cheers, Jim **************************************************************** James W. Fetzner Jr., Ph.D. Postdoctoral Fellow Section of Amphibians & Reptiles Carnegie Museum of Natural History 4400 Forbes Avenue Pittsburgh, PA 15213-4080 Lab: (412) 622-3269 Fax: (412) 622-8837 E-mail: fetznerj@carnegiemuseums.org or jwfetz@hotmail.com Personal Home Page: http://bioag.byu.edu/zoology/crandall_lab/fetzner/fetzner.htm CRAYFISH Home Page: http://bioag.byu.edu/zoology/crandall_lab/crayfish/crayhome.htm |
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