We provide an introduction to the process of applying to graduate school in ecology and evolutionary biology with information on how to prepare for graduate school, how to choose a program, how to gain admission, and how to find and select an advisor. We provide a basic step-by-step guide for the application process and for the prelude to that process. This is a much revised and updated version (Carson 1999) containing additional information on parenting during graduate school and information for underrepresented groups in ecology and evolutionary biology and first-generation college students. We hope that this guide will help students, and others get started down the right track and help them to ask more refined questions of their mentors about the whole application process. This guide applies primarily to graduate programs in ecology, evolution, and behavior, as well as other areas of organismal biology, particularly those where the prospective student will be directly admitted into a specific professor's laboratory. It may also be useful for those applying to graduate programs in other subfields of biology such as molecular, cellular, or developmental biology. In general, students should understand at the outset that applying to graduate school in these disciplines is much different than applying to undergraduate programs or applying to professional graduate degree programs such as medical or law school. Graduate schools will often use some combination of up to five primary criteria or metrics to evaluate applicants: these are grades, your scores on the Graduate Record Exam (GRE), your research experience, your letters of recommendations, and your personal statement or essay. We discuss each of these below.

Summary Difficulties quantifying pathogen load and mutualist abundance limit our ability to connect disease dynamics to host community ecology. For example, specific predictions about how differential pathogen load is hypothesised to drive host competitive outcomes are rarely tested. Additionally, although infection is known to affect mutualists, we rarely measure the magnitude of pathogen effects on mutualist abundance across host competitive contexts. We tested for both mechanisms in a plant–rhizobia–nematode system. We paired the legume Medicago lupulina with intraspecific and interspecific plant competitors, with and without a generalist nematode parasite Meloidogyne sp. Relative change in plant biomass was used to determine how nematode inoculation affected plant competitive outcomes. We counted nematode galls to test for direct effects of parasitism on plant competition and rhizobia nodules to test for indirect effects of nematode presence on rhizobium abundance. Parasites were destabilising despite similar nematode load across competition treatments. During interspecific compared with intraspecific competition, nematode inoculation decreased nodulation on M. lupulina, increased nodulation on Trifolium repens and had no effect on nodulation on Chamaecrista fasciculata. We found no support for hypothesised direct effects of nematode load on competitive outcomes and strong but idiosyncratic indirect effects of nematode inoculation on rhizobium abundance.