Symbiosis (2010) 51:67–73 DOI 10.1007/s13199-010-0077-z Symbiosis instruction: considerations from the education workshop at the 6th ISS Congress S. Patricia Stock & Seth R. Bordenstein & Joanne Odden & Darby Oldenburg & William Reznikoff & John H. Werren & Marc-André Selosse Received: 28 April 2010 / Accepted: 2 June 2010 / Published online: 25 June 2010 # Springer Science+Business Media B.V. 2010 Abstract Herein, we summarize presentations on “Symbiosis” instruction given at the Education Workshop held at the 6th International Symbiosis Society Meeting in Madison WI. We convey our teaching experiences and methods in a variety of venues. Information on target audiences, course syllabi, and laboratory skills, utilizing various symbiotic systems are also presented. We hope this review will contribute to further adoption of symbiotic interactions in the classroom as well as the growth of currently developed courses in this field—a S. P. Stock (*) Department of Entomology, University of Arizona, Tucson, AZ 85721, USA e-mail: spstock@ag.arizona.edu S. R. Bordenstein Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA J. Odden Metropolitan State College of Denver, Denver, CO 80217, USA D. Oldenburg University of Wisconsin, La Crosse, La Crosse, WI 54601, USA W. Reznikoff Education Department, Marine Biological Laboratory, 7 MBL St., Woods Hole, MA 02543, USA M.-A. Selosse Centre d‘Ecologie Fonctionelle et Evolutive, CNRS & Université Montpellier II, Montpellier, France J. H. Werren Department of Biology, University of Rochester, Rochester, NY 14627, USA specific mission of this and previous International Symbiosis Society meetings. Keywords Education . Outreach . Symbiosis . Electronic resources . High school . Undergraduate . Science teachers 1 Introduction Understanding relationships between organisms and the surrounding environment has become a nascent discipline in modern biology. Researchers have discovered a whole spectrum of interactions, between plants, animals and microbes, ranging from highly integrated obligatory to lose associations (Margulis 1998). The benefits driving these interactions are no less diverse than the organisms involved. In this respect, the term symbiosis (from the Greek: syn “with”; and biosis “living”) commonly describes close and often long-term interactions between different biological species. Moreover, symbiosis has a chameleon-like ability to blend into an impressive breadth of biology courses at many levels of education, including high school and college levels. As a topic it has the capacity to bridge divergent perspectives of the large field of biology, ranging from molecular biology to ecology. Ironically, it remains often in the background of other major disciplines. For example, when teaching respiration or photosynthesis in eukaryotes, few teachers acknowledge that these are indeed bacterial metabolisms, gained by the host cell through endosymbiosis. Similarly, plant nutrition is often taught using axenic species (eg. Arabidopsis thaliana), while the mycorrhizal symbiosis is only recognized as an example of interaction, of fungal nutrition (Selosse et al. 2004). We herein summarize presentations given at the Education Workshop organized during the 6th International Symbiosis 68 Society Congress, in Madison WI last August 2009. We describe abbreviated versions of our teaching experiences and methods related to symbiosis instruction in a variety of venues. We have focused on three topics: 1) courses for high school education, 2) courses for undergraduate college curricula and 3) online symbiosis education resources. Our diverse teaching efforts and tactics are directed to students and high school teachers with a wide-ranging view of the biodiversity, ecology and evolution of symbiotic associations. Our goal in this review is to share with the scientific community our teaching experiences, and to promote further development and adoption of symbiotic interactions in the classroom—a specific mission of this and previous International Symbiosis Society meetings. 2 Some examples of current symbiosis courses for high school education Inquiry, discovery, and modern technology are key pillars for improving modern science education and teacher training. Here, we provide information from two workshop alternatives currently available in the USA, which focus on the training of high school science teachers and students. Both courses have a common goal, the promotion of symbiotic systems in classroom lessons and the consideration of more interactive and engaging themes for science educational curricula. 2.1 “Discover the Microbes Within! The Wolbachia Project”: a high school training course One of the authors (J.H.W.) designed and initiated the integrative lab series, which was subsequently implemented and augmented by S.R.B., W. R. and J.H.W. This course comprises a series of laboratory exercises that utilize the widespread endosymbiotic bacterium Wolbachia to provide a discovery-based experience and to teach the integrative nature of biology. Through this workshop, high school teachers and students use an array of tools, resources, and laboratory experiments to make new discoveries on the worldwide frequency and genetic diversity of Wolbachia endosymbionts in insects. The key aspect of this series for students is that they have the opportunity to make novel discoveries to science while learning different biological methods. The lab series has modular laboratory exercises involving field work, biodiversity and taxonomy, molecular methods, bioinformatics, and molecular phylogeny. The modularity of the labs permits the entire series or portions to be used in the classroom. Briefly, students collect insects, learn basic identification methods and taxonomy of the insects they collected, extract DNA, screen the insects for Wolbachia by polymerase chain S.P. Stock et al. reaction, learn basic bioinformatic methods (e.g. BLAST and NCBI) using sequences from their infected insects, and learn basic molecular phylogenetic methods by aligning their sequences and using a basic phylogenetic program. The series therefore gives students the chance to discover new insects infected with Wolbachia, and in the process exposes them to concepts ranging from microbiology to molecular biology to ecology and evolution. The exercises provided in this workshop have been utilized in high school classrooms across the USA. These exercises are interspersed with brief lectures on relevant topics (e.g. symbiosis, Wolbachia biology, biotechnology, DNA sequencing, insect diversity, bioinformatics). The laboratory exercises, lectures and powerpoint presentations are available on-line at websites maintained by the Marine Biological Laboratory (http://discover.mbl.edu) and the University of Rochester (http://www.rochester.edu/College/ BIO/labs/WerrenLab/WerrenLab-Education%26Outreach. html). It should be noted that the “Wolbachia Project” can provide loaner equipment (thermocyclers and microfuges) and some key supplies (primer sets, control DNAs and control insects) to participating teachers. Below we list and briefly describe topics considered in this workshop. a. Field Exercise (Insect Collecting): Students collect insects in their local environment, either individually or in a field course outing. This field portion of the lab series enhances the students’ ownership of the research project and appreciation of field methods. b. Biodiversity and Insect Identification Exercise: Students group their insects into “morphospecies” and take photo vouchers of their specimens. Using on-line resources and working together, students determine the insect order of their collected samples. This lab provides an appreciation of biological diversity as well as the understanding of insect anatomy and taxonomy. c. DNA Extraction Exercise: These lab exercises cell biology, macromolecular biochemistry, and how to extract DNA. Students isolate DNA from their macerated insect samples. This is the first step where the students transition from naturalists to molecular biologists. d. Polymerase Chain Reaction (PCR) Screening for Endosymbionts: PCR is used to amplify insect DNA corresponding to the insect cytochrome oxidase C gene and Wolbachia DNA corresponding to the 16S rRNA gene. In addition, they learn about basic cellular organelles (mitochondria), enzymes (DNA polymerase and cytochrome oxidase) and principles of DNA structure (base pairing, denaturation and annealing). In the process, they also learn about bacterial endosymbiosis. e. Gel Electrophoresis Exercise: Students analyze their PCR amplified DNA through agarose gel electrophoresis. From this portion of the series, they make their first Symbiosis instruction: considerations from the education workshop at the 6th ISS Congress discovery—Is Wolbachia DNA present in their DNA samples and therefore is the insect being studied infected by Wolbachia? Additionally, they learn about a technology for fractionating DNA according to friction / strand length and identifying the presence of specific biological macromolecules by staining. f. Sequence Analysis and Microbial Diversity Exercise: Students, through a collaboration with the Marine Biological Laboratory, determine the sequence of the amplified 16S Wolbachia DNA (or alternatively are given a known Wolbachia sequence). Students then learn how 16S sequences can be used as a tool to identify bacteria, and the basic features of ribosomes, ribosomal sequences, etcetera. The sequence generated by the student also acts as publishable, new research product that can be uploaded to a website hosted at the Marine Biological Laboratory for students to show their teachers, peers, and family. g. Bioinformatics and Molecular Phylogeny Exercise: Students examine the relatedness of their Wolbachia 16S DNA sequences to known sequences in the GenBank database through a similarity search program called BLAST and a simple phylogenetics program. This introduces the students to basic bioinformatics techniques and the concepts of evolution at the molecular level. Teacher workshops related to the Wolbachia Project have been offered at the Marine Biological Laboratory and the University of Rochester, and also through a number of our collaborators (Muse of Fire program in Jackson, MS, Bay Area Biotechnology Education Consortium in Santa Clara, CA, Loudon County Schools in Virginia, and the Cornell Institute of Biotechnology in Ithaca, NY). In addition to teacher workshops, this program funds summer “envisionship” experiences for teacher-student pairs to work for several weeks in a professional research lab on a project aimed at studying some aspect of the Wolbachia—insect endosymbiosis. In this way the envisionships break down perceived disconnects between students and scientists, and the students have a deeper immersion into an active research lab. 2.2 “Nematode-microbe partnerships”: a teacher-training course This course was developed by S.P.S and it is taught at the University of Arizona, every-other year during the first summer session. It provides an overview of the diverse ways bacteria symbiotically interact with nematodes and considers nematode-bacterium symbioses as biological model systems. All exercises developed for this course give emphasis to activities and experimental systems that can be used easily and inexpensively in the classroom to teach basic biological 69 principles. Students become aware of how ubiquitous nematodes are and gain an appreciation of the diverse life styles they have and the habitats they live in. Lectures highlight the assortment of associations between nematodes and bacteria, which range from fortuitous to obligatory, and from beneficial to detrimental for the nematode hosts. A comparative approach is considered to describe and understand fundamental processes underlying the inter-dependency of nematodes and bacteria as a model system for other eukaryote-prokaryote symbioses. A set of integrated laboratory exercises considers nematodes of various life styles (i.e. free-living, parasitic, terrestrial, aquatic) and trophic groups (i.e. bacterivores, algivores, fungivores, predators) to teach various topics including biodiversity, ecology of trophic cascades, and gain basic skills on microscopy, molecular methods (i.e. DNA extraction, PCR, gel electrophoresis), bioinformatics, and molecular evolution (phylogeny using DNA sequences). Major topics considered in this course are listed below. a. Nematode diversity. Students gain basic concepts on nematode morphology, trophic groups. Lectures and laboratory exercises focus on both microscopy exercises and molecular methods for diagnosis and identification of major nematode groups. b. Bacteria diversity. In this section, topics such as bacteria diversity, abundance and classification are considered. Focus is placed on major groups of symbiotic bacteria of nematodes and other invertebrates including insects. c. Nematode-bacteria symbiotic associations. Lectures on this topic describe and provide examples of ecto- and endo-symbiotic relationships between nematodes and bacteria. Emphasis is placed on the establishment and maintenance of these associations. Moreover, students learn the role of bacterivore and plant-parasitic nematodes in plant health and soil ecology. Laboratory sessions engage students in various techniques including nematode isolation from soil and fresh water samples, “insect bating” methods for isolation of insect parasites, isolation of nematode endosymbiotic bacteria, and bacteria culturing methods. d. Nematode morphology and natural habitats. Through this section students appreciate how nematodes, like all other organisms, are adapted to their natural habitats by relating morphology with the places they live in. Laboratory exercises focus on a variety of nematode forms, and through their examination students relate morphology and function. e. Movement and feeding strategy. Students observe various nematode shapes and size and relate these traits to their movement in different substrates (i.e. agar, sand, water). They also assess how nematodes adapt 70 and what strategy they use to search for their food source (i.e. plants, animals, microbes). They also examine nematode mouth parts and relate mouth morphology and structures with their feeding habits. For example, how does the mouth part of an algivore nematode look like? What are the teeth or claw-like structures that certain nematodes have for? f. Reproductive strategies. Students gain appreciation of the different ways nematodes reproduce and are introduced to the concept that for certain nematodes (i.e. filarids), bacterial symbionts play a key role in their reproductive fitness. Laboratory exercises comprise microscopy examination of various nematode types and recognition of sexual organs, differentiation between male and female. Students also conduct a mating exercise considering bisexual nematodes. g. Physiological adaptations and the environment. Students gain knowledge on how organism such as nematodes can adapt to survive under harsh environmental conditions including temperature, moisture, UV exposure, etc. A series of experiments are designed to help students learn how nematodes can adapt by observing morphological changes and behavior in response to extreme environmental conditions. 3 Symbiosis in the undergraduate college curricula As mentioned before, the academic separation of biology into narrow sub-disciplines does not mirror complex symbioses in which organisms of all sizes interact with one another. This segregation also hinders the understanding of unified systems. Unfortunately, not many formal courses exist on this topic for undergraduate education. We herein summarize examples of one formal undergraduate course with focus on symbiotic interactions and one undergraduate research project that also considers a symbiotic system. 3.1 “Living in Symbiosis”: an undergraduate course experience This course was developed and is taught by S.P. S. at the University of Arizona. It is a 3-credit course and it is taught every fall semester. This course has gathered undergraduate students from various academic programs including Veterinary Sciences and Microbiology, Molecular and Cellular Biology and, Ecology and Evolution (http://cals.arizona.edu/ ento/courses/ento310/index.htm). The course provides an overview of the diversity of associations that exist between microbes and eukaryotic hosts. Emphasis is placed on symbiotic associations with relevance to human medicine, S.P. Stock et al. veterinary sciences and agriculture. Major topics covered in this course are listed below: a. Symbiosis and the eukaryotic cell. This initial section introduces students to the various hypotheses that explain the origin and evolution of the eukaryotic cell. b. Ecology of symbiotic associations. Students acquire knowledge on the various symbiotic interactions and the concept of the symbiotic continuum. c. Evolution and genetics of symbiotic associations. Key topics in this section include genetic interactions in symbiotic systems; gene for gene relationships; genetic polymorphism and symbiont genomics. Students are also introduced to topics such as the nature of host resistance, coevolution and evolution in a symbiont environment. d. Behavioral symbiosis. Students become familiar with cleaning and social symbioses. A number of video clips and documentaries are used to exemplify these interactions. Subsequent units in this course focus on the «symbionts» including: viruses, bacteria, fungi, protists, helminths and plants. Students are first exposed to an introductory lecture on taxonomy, morphology and diversity of each symbiont group. Additional lectures focus on the interactions each of these groups have with other organisms (i.e. vertebrates, invertebrates, plants, etc.) in both aquatic and terrestrial systems. Topics such as adaptations, coevolution and consideration of symbionts as models systems are also included. 3.2 Symbiotic models: tools for classroom lessons and laboratory techniques The importance of research at the undergraduate level cannot be over-emphasized. Allowing students to develop good laboratory techniques, become well-versed in reading and analyzing scientific literature and develop creative and critical thinking skills will prepare them for a fruitful future in science. Thus, the best undergraduate research projects are those that enable students to gain aptitude and experience with numerous techniques and a subject that embodies both applied and basic research. In this respect, we summarize below an undergraduate assignment that is part of an introductory microbiology course, “A General Survey of Microbiology” (BAC 101), a freshman level general microbiology course taught by D.O., at the University of Wisconsin-La Crosse. This project focuses on symbiotic interactions between the composting worm, Eisenia foetida and the bacterium, Verminephribacter eiseniae. Specifically, this project, entitled “Earthworms revisited” is a handson-activity that considers earthworms and their symbionts. 3.2.1 Background on the earthworm-bacteria symbiosis The composting worm, Eisenia foetida is gaining wide acceptance as a complex and useful model for scientific Symbiosis instruction: considerations from the education workshop at the 6th ISS Congress inquiry. While many will remember a past biology lab in which an earthworm was dissected, the worm and its biology has since come into its own as a viable and useful teaching tool. An important feature of this model system is the newly discovered symbiosis between the worm and the bacterium, Verminephribacter eiseniae (Schramm et al. 2003; Pinel et al. 2008). This bacterium colonizes the nephridia (kidney-like organ) of the worm and is vertically transmitted to new generations through deposition into the nascent egg capsule such that newly hatched worms emerge colonized (Davidson and Stahl 2008). Because of the intricate association of these worm-associated bacteria and the ease with which it can be studied in the laboratory, this symbiotic system can be used in an undergraduate course to not only demonstrate symbiosis but to allow students a hands-on opportunity to investigate the symbiotic relationship. Furthermore, since little is known about the exact role the bacteria play this system lends itself to independent student investigations regarding the symbiosis between E. foetida and the recently described V. eiseniae. 3.2.2 The classroom project Students are presented with the vermicomposting system in a short lecture and then asked to do some research outside of class about vermicomposting. For the purpose of this project, students are required to identify a bacterium from the vermicomposting system which is maintained at UW-R. Students work in pairs to come up with a hypothesis and research plan aimed at identifying this bacterium that is present in the vermicompost system. The students may choose to isolate microbes associated with the worms and/or the castings. During the project, the students also isolate V. eiseniae from the worms and read the hallmark paper by Pinel et al. (2008). Once bacteria are isolated and streaked for purity on agar plates, students perform a battery of biochemical tests to identify the bacteria at the genus level (and if they are lucky—the species) to which their isolate belongs. In the future, a molecular diagnostics component will be added to the project whereby students will have the chance to sequence 16S rRNA genes of their isolate for more accurate identification and gain expertise in various molecular biology techniques, including DNA extraction, PCR, pre-sequencing treatment methods and sequence editing/analysis. There are many superior logistical features of E. foetida system that allow for its simple incorporation into a biology classroom. The worms are widely available (we obtained our colony from www.wisconsinredworms.com) and inexpensive while being simple to maintain and breed. Once a population of worms is established it will quickly degrade classroom/campus waste products, and the worms and their waste (castings) are also a valuable product that has a potential market value. The features of this system can expand the curriculum to a variety of interdisciplinary courses such as chemistry and business. 71 4 Building a network of online symbiosis education resources A current trend in pedagogy is to draw from multiple resources to design a course, as well as to present some course material to students via multimedia outlets. Using multimedia in the classroom has the benefit of breaking up a lecture and addressing different learning styles. It is clear that, like any course materials, multimedia should be carefully considered for the audience and learning objectives. Supplementary resources may also provide educators the opportunity to rejuvenate course material. In this respect, the internet provides an excellent venue to share teaching resources. In teaching symbiosis at the college level, two major challenges are found: 1) a dearth of symbiosis textbooks currently published, in particular for the introductory college level (with little or no symbiosis material presented in many general biology textbooks) and, 2) no central repository for symbiosis education resources online. Writing and publishing a textbook is a major-undertaking (see below section 5), and the breadth and depth of symbiosis topics as well as perhaps current low-demand worldwide to teach devoted general symbiosis courses make this a challenging component to immediately address. Even with the best of textbooks, it is generally considered good practice to incorporate material from multiple sources when preparing course materials. Hence, a symbiosis education resources website may be an immediate solution, as well as augment any current or future textbooks. We herein discuss MuSER, a website developed by J. O. at the Metropolitan State College of Denver, (http://sites. google.com/site/symbiosiseducationresources/). This website focuses on mutualistic teaching resources to introduce readers to the topic of symbiosis. It was designed to be used by college faculty teaching the topic of symbiosis and/or their students, whether symbiosis is taught as a topic within a broader course, or as a specialty symbiosis course. The website contains links to other symbiosis websites, course syllabi, animations and readings. The content of the MuSER website is divided into three categories: – – – Website and Animation Links for Selected Mutualisms and Symbiosis Topics Selected Readings for College Courses Symbiosis Course Syllabi 4.1 Website and animation links for selected symbiosis topics This section of the website is organized by the following topics: 1) endosymbiosis theory, 2) introduction to symbiosis, 3) photosynthetic mutualisms, 4) chemosynthetic mutualisms, 5) luminescent mutualisms, 6) cellulose 72 degrading mutualisms, 7) nutritional mutualisms (such as insect/bacteria, lichen, and plant/mycorrhizae), 8) shared mechanisms of mutualism and parasitism, 9) symbiosis research, and 10) general information to supplementary readings (including weblinks to endocytosis, microbial ecology, and element cycles material). The links within each topic feature animations, content information, and/or videos. 4.2 Selected readings for college courses In this section MuSER provides lists of various literature references for upper division, lower division college courses and general background reading resources. Nontextbook readings are usually incorporated in college level courses, especially to supplement and/or expand concepts considered in primary literature and/or textbooks. Primary literature is an effective tool in high school courses (Yarden et al. 2001), however at the college level it is critical that students have access to the most up-to-date information. Also, for introductory courses (non-majors or majors) additional selected readings may be useful. For example, naturalist readings and/or publications written by scientists to an introductory science audience, such as The Lives of a Cell: Notes of a Biology Watcher (Thomas 1974), will provide students background knowledge to understand more in-depth topics of symbiotic topics. 4.3 Course syllabi This section includes syllabi from college courses that had either the theme of symbiosis or were a full course on symbiosis. Course syllabi are categorized as upper division, lower division majors, or non-majors. 5 Final remarks The decision to highlight education at the International Symbiosis Society Conferences reflects the importance of the field in the biological sciences. Arguably, symbiosis is experiencing a new, modern synthesis—one akin to the modern evolutionary synthesis of the early 20th century that married evolution and genetics. The modern evolutionary synthesis however did not take into account symbiosis, which on one hand adds complexity to understanding a living organism, but on the other hand is as essential as genetics to understanding organismal fitness and speciation. Darwin and the 20th century pioneers of evolutionary biology would have been astonished to see the role symbiosis has played in shaping modern day biology. Symbiosis itself is evolving towards a central position within the reticulated system of diverse biological disciplines. S.P. Stock et al. Teaching this new emphasis on symbiosis is important and leads to a better integration of the biological sciences. How can we engage ‘non-symbiologist’ teachers to integrate symbiosis in their teachings on nutrition, ecology, evolution, development, etc.? Easily accessible resources such as protocols, lectures, videos, and equipment. Are key for this purpose As mentioned above, textbooks have a role to play but they are slowly evolving (in a punctuated way, from edition to edition) and less easily accessible. On the other hand, their publication can be a milestone, creating opportunity for comments or analytic reports that make light on the supported concept. For instance, the experience of writing a book on symbiosis in French (Selosse 2000) produced noticeable outcomes on the teaching of symbiosis in France. It made new research and concepts available and allowed a revival of the teaching of symbiosis. The French national high-school programs now include some sections on mycorrhizae, symbiotic origin of some eukaryotic organelles, and coral symbioses. At the French national examination that annually recruits biology teachers for state high-schools (Agrégation des Sciences de la Vie), the number of questions on symbiosis at the oral part of the examination raised from 3–4 per year in the 80’s to about 30 per year (out of ca. 150). An obvious (and easier) alternative to writing a book is, of course, the translation of existing recent books (e.g. from English, Douglas 2010)— but the problem is that examples in the book may not be biogeographically or culturally relevant. Moreover, illustrations and synthetic drawings are needed for teachers: They ensure a clear picture. In the previous example, an illustrated atlas was produced (Duhoux and Nicole 2004) as well as a film (Gabriel 2007) that made available basic and more or less raw data for teaching. This added to the potential for including symbiotic facts in various other topics. Part of the job of science is to transfer knowledge from researcher to teachers, especially for knowledge on symbiosis that is not in textbooks. For this, inviting teachers to join either general meetings or parts of meetings devoted to teaching is very appropriate. Involving more university teachers willing to do some outreach about symbiosis is also important. Coming back to the example of France, French teachers from universities and higher sections in high schools were engaged to join a congress on endosymbiosis in Roscoff, with the help of the Centre National de la Recherche Scientifique (http:// www.sb-roscoff.fr/ETSymbioses2008/prog.html). Two series of general review papers in French, rich in illustrations, issued from this meeting and were published in Biofutur, and these papers are freely available on the meetings’ web pages, with the publisher’s authorization (http://www.sb-roscoff.fr/ ETSymbioses2008/index.html; Martin and Selosse 2009; Selosse et al. 2009). Symbiosis instruction: considerations from the education workshop at the 6th ISS Congress Finally, for the International Society on Symbiosis (ISS), the implication of teachers in ISS meetings has always been an important task since the Woods Hole meeting in 1997. The organization of a session on teaching was always accompanied by a practical observation of living material, with using microscopes, dissections and pictures, organized by specialists presenting their own model in a classroom. This is a place for exchanging experiences and know-how among teachers and researchers. We hope that the original and successful programs described in this chapter will enhance these important efforts. Acknowledgements We acknowledge the various funding agencies who have contributed to the creation and maintenance of many of these teaching resources. The Wolbachia Project was originally funded by a National Science Foundation grant to J. Werren (EF-0328363) and a NASA Astrobiology Institute (NNA04CC04A) grant to the Marine Biology Laboratory in Woods Hole, MA. The Biology Department at the University of Rochester assisted with teacher workshops. Funding from the Howard Hughes Medical Institute Precollege Science Education Program to S. Bordenstein and W. Reznikoff (award # 51006093) provides continued support for workshops and national expansion of the education program. The nematode-bacterium symbiosis courses for teachers and undergraduates and undergraduate training in S.P. Stock laboratory, University of Arizona are funded by various NSF awards including Research Experience for Teachers and Research Experience for Undergraduates programs (awards # 0924125, 0822631, 0733729, 0724978) and a Research Coordination Network award (NEMASYM) (NSF-IOS # 0840932) to S.P. Stock. M.-A. 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