The Ecological Society of America annual meeting 2019 was held in Louisville from August 11 to 16th and Associate Editor Frederik De Laender kindly agreed to share his thoughts and experiences from the meeting below.

Louisville, the city of Mohammed Ali, hosted this year’s ESA meeting (#ESA2019, August 11-16th), themed “Bridging Communities & Ecosystems: Inclusion as an Ecological Imperative”. The meeting was nowhere near a boxing match though. I found the general atmosphere quite enjoyable and friendly, with speakers communicating results in an honest and open way, often making clear they were looking for feedback, the results were preliminary, etc.
One thing I appreciated as well is that most talks I’ve seen started from a broad system-independent conceptual question, and only then narrowed down to the study system. As a disclaimer, I should probably add that it is very possible I selected for such talks, since I am forced to be interested in system-independent questions, lacking expertise on any specific system. I should also add that, despite good intentions and the meeting app, I did miss quite some talks that I wanted to see because of obvious reasons (in a conversation, constraints imposed by the venue’s dimensions, etc). So this overview is very incomplete and anecdotical.
One specific topic that seemed recurring was intraspecific trait variation, both as a factor and a response variable, and often in empirical studies. I wonder whether that’s the result of the recent surge in theoretical studies seeking how this variation may (or may not) matter for population growth and coexistence. Speaking of which: coexistence theory seems to be applied increasingly. The now classic plane of niche and fitness difference (N and F), showing where coexistence occurs or where exclusion happens, featured on quite a number of introduction slides. These applications, across a variety of systems, demonstrate the power of the theory: it offers a framework to structure our thoughts and formalize our ideas on (for example) how environmental conditions change species interactions. I felt that one challenge ahead, however, could be the interpretation of these quantities, and their comparability across systems. Different talks used different definitions to compute N and F, depending on the studied system.
Speaking of which (again): What is theory? I always thought ecological theory is embodied by ideas formalized into mathematical equations, ideally treatable analytically after simplification, and leading to insights that do not overly depend on the chosen parameter range. One session dealt with the question if and how to relax these constraints, as to include simulation models. It was argued these models can formalize ideas too, albeit using algorithms instead of equations, and allow including the complexity that mathematical equations waive. I can’t think of a compelling argument in (dis)favor of this argument, so I prefer to remain agnostic here. I guess what matters more is to use the right tool for the right question, rather than if something can be labelled theory or not.
Like all meeting, the #ESA2019 was at times haunted by computer ghosts. I’ve seen two speakers continuing their talks without slides, which was… great, actually. It made me think about a potential experiment for future meetings: what about a session where speakers weren’t allowed to use slides? No slides force us to go to the essence of things more quickly. Plus, it actually makes the talk easier to follow, as there’s only one focal point (the speaker) instead of two (speaker and screen). Too often are we locked in the format – feeling that we need to have a slide for each important statement. What about whiteboards? Hand-outs with details for during the poster session? Well, I might just try presenting a talk without slides next year, let’s see.
Frederik De Laender, Associate Editor of Journal of Ecology, Université de Namur ASBL, Belgium