From EAM94001@UCONNVM.UCONN.EDUTue Apr 29 15:01:33 1997 Date: Mon, 11 Nov 1996 11:22:06 -0500 From: eduardo To: Multiple recipients of list ALGAE-L Subject: Phenotypic plasticity responses Dear fellow phycologists: Thank you very much for your kind responses!! As promised, a list of all of the responses that I received from you follows: I am a graduate student at the University of Connecticut. My doctoral project deals with a subject in which diatom systematics plays an important role. An add itional interest that I have is the topic of phenotypic plasticity. One of my objectives is to account for some examples of phenotypic plasticity among the algae, whether microscopic or macroscopic, closely or distantly related. Thus, let me ask the following questions: If you were to present one example of phenotypic plasticity in the algae, what group of organisms would you select? What genus/species would you choose to highlight? Thanks in advance. For those who might wish to respond to me, my address is eam94001@uconnvm.uconn.edu. Eventually I will distribute a summary of responses to the list. Eduardo A. Morales, Ecology and Evolutionary Biology University of Connecticut, Storrs 06269-3042 ======================================================================== I would suggest the ectocarpales, perhaps even Ecotocarpus siliculosus itself, which I know is extremely plastic based on my own extensive observations. From my point of view you can make them look about like anything within their morphological repretoire by the right combination of environmental effects. Russ Meints Russel Meints, Director Center for Gene Research and Biotechnology Oregon State University Corvallis, OR 97331 ======================================================================== I am just beginning a research project at the US EPA in Narragansett, RI that investigates the role of both phenotypic plasticity and somaclonal variation in the adaptability of macroalgae to stress. I'm working with the marine red alga, Champia parvula. I look forward to hearing what others have found already...please feel free to contact me directly if you are interested in what I'm trying to do... Glen Thursby thursby.glen@epamail.epa.gov ======================================================================== I'd look into the desmids, especially Cosmarium. A number of species seem to be highly plastic, but in some cases you may have to perform SEMs to notice it (in other cases, overt morphology is an immediate cue). -- Stephen Gough Biol. Sci./Mary Washington College sgough@s850.mwc.edu 540-654-1422; 540-654-1081(fax) ======================================================================== How about toxin spectra in Alexandrium species? Not only extremely interesting but important too!! ---------------------------------------------------------------------- Tim Wyatt IIM - CSIC Eduardo Cabello 6 Ph: +34 86 231 930 36208 Vigo (Spain) Fax: +34 86 292 762 ----------------------------------------------------------------------- CONCERNING DIATOMS, ONE OF THE TYPES OF PHENOTYPIC "PLASTICITY" I THINK IS INTERESTING, AND UNEXPLAINED, IS HETEROVALVY -THE ONE-DIVISION SWITCH FROM ONE VALVE TO ANOTHER. SOME OF THE EXAMPLES WE HAVE PUBLISHED FOLLOW. THERE ARE MANY OTHERS. STOERMER, E. F. 1967. POLYMORPHISM IN MASTOGLOIA. J PHYCOL. 3: 73-77. TUCHMAN, M. L., E. C. THERIOT, AND E. F. STOERMER. 1984. EFFECTS OF LOW LEVEL SALINITY CONCENTRATIONS ON THE GROWTH OF CYCLOTELLA MENEGHINIANA KUTZ. ARCHIV. PTROTISTENKUNDE 128: 319-326. GENE STOERMER UNIV. OF MICHIGAN STOERMER@UMICH.EDU ======================================================================== My pime example of phenotypic plasticity comes from my own research on Ceramium which I did in the mid 1970s on the Ceramium rubrum complex in Nova Scotia. In that work I pointed out that cortical band morphology was largely controlled by daylength and that a number of previously defined species and subgenera could not be maintained. Accordingly, I suggested that at least three species previously recognized in eastern Canada were the same and that ca. 15 additional European species should also be synonymized. Although this conclusion had to be revised somewhat based on subsequent crossing experiments, the original phenotypic plasticity that I observed was still pretty impressive. This experience clouded my perspective on algal taxonomy for many years. The Ceramium work was published as: Garbary, Grund & Mclachlan 1978. The taxonomic status of Cermium rubrum (Huds.)C.Ag. (Ceramiales, Rhodophyceae) based on culture experiments. Phycologia 17: 85-94. I would like to see your list when it is finally put together. ========================================================================== David J. Garbary phone: 902 867-2164 Department of Biology fax: 902 867 2389 St. Francis Xavier Univerity email: dgarbary@juliet.stfx.ca Box 5000 Antigonish Nova Scotia, Canada B2G 2W5 www: http://juliet.stfx.ca/people/fac/dgarbary/botany.html ========================================================================== ======================================================================== Have you thought about the cyanophytes? One of the biggest problems we've been facing has been to determine the extent of morphological variation of certain taxonomically important features in that group of organisms. Dr. Simone M.F. Silva Department of Botany University of the Witwatersrand Private Bag 3 2050 - Johannesburg SOUTH AFRICA Phone (+ 27 11) 716-3827ing ======================================================================== In response to your message on algae-l and PSA, if I were to choose one example of phenotypic plasticity in the algae then it would unquestionably be of seaweeds in the genus Fucus. The literature is easily available, but if you want details of any references then please let me know. Dr. F.G. Hardy, Department of Marine Sciences and Coastal Management, University of Newcastle, Newcastle upon Tyne, NE1 7RU, U.K. e-mail: f.g.hardy@ncl.ac.uk tel: 0191 222 6661 fax: 0191 222 7891 ======================================================================== this is a fascinating topic, I did my honours looking at some of these ideas. I was working on the green alga Caulerpa - which is a coenocyte and generally a good genera to work on. Here are a couple of refs to get you going... Enomoto, S. and Ohba, H. 1987. Culture studies on Caulerpa racemosa (Caulerpales, Chlorophyceae) 1. Reproduction and development on C. racemosa var. laetevirens. Jap. J. Phycol. 25(3): 167-177 Ohba and Enomoto. 1987. Culture studies on Caulerpa racemosa (Caulerpales, Chlorophyceae) II. Morphological variation of C. racemosa var. laetevirens under various culture conditions. Jap. J. Phycol. 25(3): 178-188 But beware!!!!! (I tried and the following resulted!!) Carruthers, T.J.B, Walker, D.I. and Huisman, J.M. 1993. Culture studies on two morphological types of Caulerpa (Chlorophyta) from Perth, Western Australia, with a description of a new species. Bot. Mar. 36: 589-596 Tim Carruthers, Botany Department, University of Western Australia, Nedlands 6907, Western Australia, Australia, ph:(09) 380 2217, fax: (09) 380 1001 e-mail: timc@cyllene.uwa.edu.au ======================================================================== You might want to look at my recent article: Gordon, R. (1996). Computer controlled evolution of diatoms: design for a "compustat" Nova Hedwigia 112, 213-216. -------------------------------------------------------------------- Dr. Richard Gordon, Department of Radiology University of Manitoba, Room ON104, Health Sciences Centre 820 Sherbrook Street, Winnipeg, MB R3A 1R9 Canada Phone: (204) 789-3828, Fax: (204) 787-2080, Home: (204) 589-0411 E-mail: GordonR@cc.UManitoba.ca ======================================================================== Responses of macroalgae to salt tolerance, in particular species of macroalgae foun in the Baltic Sea and conspecific popoulations in the North Sea. ..or, likewise salt tolerance in macroalgae along estuaries. I would highlight t e brown algae including species such as Pilayella spp., Ectocarpus spp., Fucus spp., Chorda sp. , but also some green spp such as Cladophora. David Thomas OSS102@SOS.BANGOR.AC.UK ======================================================================== AMONG THE DIATOMS TRY PHAEODACTYLUM TRICORNUTUM. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Michael A. Borowitzka School of Biological & Environmental Sciences Murdoch University Perth, W.A. Australia tel: +61 9 360 2333 fax: +61 9 360 6303 <<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>> ======================================================================== There are several examples of plasticity in the shape or chemistry of one algal species. There have been various cases studied in which either the flow regime, or the level of herbivory causes the same alga to grow on different forms. Also, levels of grazing can induce adventitious branching or chemical defenses, and alternating stages of the life history of an alga may have different characteristics. To be of any help, it would be necessary that you define "phenotype" for your purposes. The fact is that almost none of these studies have looked at the genetics of their algae(with the exception of studies that have focused on haploid vs. diploid phases of the same plant, in which you know inherently there is a difference). The other case that comes to mind, which may be more along the lines of "true" phenotypic plasticity, is from bioassays that have looked at the effects of red tide toxins by looking at toxic and non-toxic CLONES OF THE SAME DINOFLAGELLATE SPECIES. Edwin Cruz-Rivera Ph (919) 726-6841 Institute of Marine Sciences Fax (919) 726-2426 University of North Carolina, Chapel Hill email: ecruzriv@email.unc.edu 3431 Arendell Street Morehead City, NC 28557 ======================================================================== I've never considered Phenotypic Plasticity in the micro-algae. If I were to pick an ideal subject I'd probably go for the macro-green Caulerpa which I believe shows amazing plasticity - I seem to remember (but could be completely wrong) that it grows from a stolon and individual plantlets from the same individual plant can be so variable in phenotype that they have been thought to be distinct species! At the moment I'm interested in the plasticity exibited by the Fucoid Browns - I'm looking at a number of contributing factors - but the only one I've published on is to do with the impact of hybridisation: Scott, G.W. and Hardy F.G. (1994) Observations on the occurrence of hybrids between two sympatric species of Fucoid algae. Cryptogamie, Algologie. 15(4) pp 297-305 Dr. Graham Scott University College Scarborough Scarborough N. Yorks YO11 3AZ grahams@ucscarb.ac.uk From EAM94001@UCONNVM.UCONN.EDUTue Apr 29 15:03:32 1997 Date: Tue, 26 Nov 1996 14:31:45 EST From: eduardo To: ALGAE-L@Danann.hea.ie Subject: phenotypic plasticity II (sum) Fellow phycologists: Thank you very much for your responses. Here is a summary of them. ======================================================================= I do not think that the Bangia / Conchocelis case is phenotypic plasticity. It is part of its life cycle -- all life cycle events, that I have studied are triggered by environmental factors. I feel that phenotypic plasticity deals more with the morphological changes seen among individuals of the same species put into different environmental conditions. Yeah -- Bangia and Conchocelis are different morphologies, but they are different life stages. The interesting thing, I believe, that defines phenotypic plasticity is that a plant that is transplanted to different conditions will have grown one way for years, then will adjust its new growth (and in some cases I imagine its old growth) to meet the new environmental conditions. I would love to see how people respond to your note on "Algae-L". Matthew B. Sullivan MSULLIVAN@SOUTHAMPTON.LIUNET.EDU SOUTHAMPTON COLLEGE ======================================================================== Soy un estudiante argentino de Ph.D., trabajando en Ecologia de Macroalgas, bajo la direccion del Dr Robert De Wreede. Phenotypic plasticity es la variabilidad en formas que puede tomar un dado genotipo segun su expresion es influenciada por el ambiente. Acordate que FENOTIPO = GENOTIPO + AMBIENTE en cualquier organismo. Debido a dicha definicion, el ejemplo de alternancia de generaciones NO ejemplifica plasticidad fenotipica, pues estamos hablando de 2 genotipos distintos (las 2 generaciones que mencionaste de Bangia, por ejemplo). ========================================================= Ricardo Scrosati The University of British Columbia Department of Botany Vancouver, BC V6T 1Z4, Canada Phone (home): 1-604-221-1034 Phone (office): 1-604-822-6785 FAX: 1-604-822-6089 ========================================================================== If you are interested in phenotypic plasticity in higher plants it might be worthwhile checking out heterophylly in some aquatic angiosperms, especially water buttercups (Ranunculus spp.) Colin Pybus Dept of Life Sciences Regional Technical College Galway Ireland CPYBUS@aran.rtc-galway.ie ======================================================================== I'm not too sure about Bangia, but alternation of generations in Porphyra, also in the Bangiales, seems to have at least some points in its life history at which it is rather closely controlled by the environment. For example, formation and release of conchospores on the conchocelis plants is generally triggered by two different combinations of day length and temperature. The formation of spermatia and carpogonia on gametophytes is, as I recall, generally also under environmental control. These triggers synchronise the life history of the plant to match either seasonal patterns or, in the case of at least one epiphytic form (Porphyra nereocystis), growth patterns of host species (which themselves are necessarily seasonal). The environmental windows for spore formation etc. are species-specific and as far as I know vary little across generations and as a result responses to cues for spore formation etc. would not generally be regarded as plastic (the nori industry would be struggling if they were). On the other hand, there are some recent publications which propose far more plastic life histories in the genus than were suspected when research was turning up the well synchronised life histories noted above. Certainly, there are species where the life history is not obligately haplo-diploid with differing morphologies for each ploidy level. The uncoupling of ploidy from morphology in some species has been demonstrated. As such, neither syngamy nor diploidy is are prerequisites for conchocelis formation. The studies of sexuality in Porphyra that I have read came to the conclusion that sex is determined by one gene only. As such, the only real genetic difference between conchocelis and gametophyte is the ploidy level. The ploidy-morphology uncoupling supports this. Not surprisingly, the genes expressed during the conchocelis stage are not always the same as those expressed by the gametophyte. Its not clear, as far as I know, just where strict environmental control of life histories leaves off, or when it is that the developmental path of a cell becomes fixed. Certainly, as evinced by the studies on life histories and environmental triggers, most developmental pathways are predictable (syngamy -> carpospores -> conchocelis -> conchospore formation ...). * Unfortunately I am miles from home and so miles from any references that I could point you towards, or check myself to make my reply somewat less sketchy. Neil Griffin University of Cape Town (normally griffin@botzoo.uct.ac.za) ======================================================================== Eduardo- Phenotypic plasticity is the variable expression of a genotype caused by differences between different environments. It should probably be defined sensu stricto, therefore, as those variations that are environmentally induced. Many of the examples you asked about, like alternation of generations are ploidy effects that are strictly a genetic phenomenon (i.e., environmental variation does not necessarily cause the alternation of generations, that is a genetic and developmental phenomenon). I suggest that you not restrict yourself to asking among phycologists what is and what is not phenotypic plasticity. Go to the evolutionary biology literature and read about recent discussions in phenotypic plasticity. Here are some authors who study the topic to get you started; (sorry, I don't have the full references with me, however, these names are well-known in the field of phenotypic plasticity and should give you plenty of papers to start with). Stephen Stearns (A recent book entitled The Evolution of Life Histories (1992) has discussions of phenotypic plasticity), John Thompson (a paper in TREE in 1991 reviewing the evolution of phenotypic plasticity). Sara Via, Carl Schlichting, Massimo Pigliucci, M(?). DeJong, and others have done recent papers in TREE in 1995, 1996, and there was a special section of about 30 or so pages devoted to the topic in a 1993 issue of the American Naturalist (starts on page 352, I believe). Scheiner did a paper in 1993 in the Annual Review of Ecology and Systematics. There is a classic paper from 1965 by Bradshaw (cited in almost all the above references) that discusses phenotypic plasticity in plants. Stearns also did a review in 1989 in Bioscience. That should get you going. STEVE DUDGEON ======================================================================== wrt #1, i cannot think of a hetro morphic life history as an example OF PHENOTYPIC PLASTICITY. i hope you give a resume of people's thoughts Bill farnham Univ portsmouth, england ======================================================================= Best regards, Eduardo A. Morales