Scientific Presentations: the Dos and Don'ts

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With the ESA submission deadline just passing, the Cadotte Lab decided that it would be helpful to dish out a few tips on how to make a presentation that is both enjoyable for your audience and fun for you to give. Presenting in front of people is never easy; giving a presentation about your own study can be even harder since you have to condense months (or even years) worth of information into a 15 minute time period. So with this in mind here are a few tips for each of the main sections of a presentation:

Note, the percentage by each section heading indicates the relative amount of time you should spend on that section.

Title Slide (5%)

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This is the first chance you’ll get to catch your audience’s attention, so be interesting!

The title of your presentation depends on the type of audience you’ll be presenting to, so gauge it accordingly. If your audience is a bunch of people with only general biology backgrounds or people that are from completely different fields then don’t complicate things using heavy jargon.

Generally for the title, you want to:

• Be witty and interesting
• Convey the main message or main result from your study

If you’re speaking to a broad audience it could be helpful to have a broad title and then separate it from a more specific title.

Besides the title you’ll also want to include your name and affiliation. Depending on the type of talk, for instance an honors thesis, you should also include your supervisor’s name. If you are collaborating with many people on a study you should also include their names. However, make sure that your name is on the first slide, since you are the presenter, and then on a second slide include a special acknowledgement of the other people involved. It’s also recommended that you acknowledge these people throughout the talk, such as in the methods. 

Introduction (10-15%)

Don’t make this section too long. Give just enough background that the audience can understand the concepts that you’ll be discussing and how it relates to the question you are trying to answer.

Generally for the introduction, you want to:

• Have the background information displayed in a simple to understand way
• You could use info-graphs here to reinforce an idea
• By the 2^nd or 3^rd slide you’ll want to state your study objectives or hypotheses
• You could create ‘toy’ graphs to describe your hypotheses / predictions

Methods (10-15%)

Be very concise with this section. Everyone understands that a lot of work went into performing your study; however, you don’t want to overwhelm your audience with all the nitty-gritty things you had to do. Give enough detail that people understand what you did and if possible try and summarize your methods in a simple figure.

Generally for the methods, you want to talk about:

• The treatments used, sample size, the measurements taken and how they were done, and the statistics that you performed

A note on statistics: try to steer clear of very complicated statistics. Most likely your audience will have a basic understanding of stats, but you may lose people if you get too complicated. When talking about your stats, make sure that you can give an easy to understand explanation of how they work.

Results (50%)

This is the biggest and best section; it’s where you get to show people all the cool and exciting things you’ve done! However, the only way you can convey how awesome your results are is by clearly explaining them.

Generally for the results, you want to:

• Stick to the main results
• You may have a lot different results but always make sure that what you are describing relates directly to the main message of your study
• Don’t overwhelm your audience
• Always thoroughly describe your graphs
• Describe what variables were you examining (the axes)
•  Why is the graph important?
• What is the relationship that the graph is showing?
• The title of the slide could be used to state what the result is
• You’ve spent a lot of time making these graphs and analyzing them - so you know them very well, but your audience doesn’t yet. Take time to walk them through the graphs.
•  If you’re showing several graphs in sequence, make sure to note if the axes are changing
•  If the graphs are very similar it might be helpful to have a break between slides or to use an animation.
•  Don’t show too many stats
•  Just state the p-values and which stats were used
• Avoid tables if possible
•  Summarize all the information in an easy to follow figure
•  If you can’t avoid using a table make it as appealing as possible
•   Highlight key parts or add arrows to show trends if they exist

Discussion (20%)

Now start bringing everything back together. Your audience may have gotten lost during your results section, so now is the time to refocus them so that they can see the big picture.

Generally for the discussion, you want to:

• Restate your hypotheses
• Restate you main results
• Describe how you could improve your study
• Describe the next steps for your work and the field in general

In the end you’ll want to describe the broader implications of your work and give the audience a take home message so that they know that your work is bettering the field in some way.  

Acknowledgements (5%)

Don’t forget to thank everyone who has helped you through this whole process! This includes your supervisor, people who helped you with data analysis or revising your paper, or all the volunteers you helped you conduct your field work or lab work. You’ll also want to acknowledge your institution as well as anyone who provided funding to your project.

General tips

Here’s a quick list of tips to use throughout your presentation:

• Use large text font
• Don’t be flashy, make sure it’s easy to read

• Don’t put too much text on a slide
• This distracts the audience

•  Don’t put any important point (text or an image) at the bottom 1/3^rd of a slide
• Depending on the room you are presenting in it may be very hard for the audience to see it
• In general, try and keep everything within the top 2/3^rd of the slide

• Don’t put too many animations on a slide
• This can be very distracting for the audience

• Don’t read off your slides
•  Use presenter view if you can’t memorize everything

• Including outlines
•  Not necessary in a short talk, but could be helpful in a longer talk

• If you run out of time
• Panic on the inside not the outside!
• Acknowledge that you’re running out of time and start wrapping things up
• Start talking about the broad implications of your work and maybe future directions you plan to take
• If you have more slides, skip over them but tell the audience what you were planning on showing. If they ask questions about what you were going to show you can go back to those slides

• Don’t talk too fast!
• Everyone gets nervous! Take a deep breath and calm yourself down, the calmer you are the easier it is for your audience to follow you

#ESA2014 Day 4: Battle Empiricism vs Theory

You are our only hope!(?)

First off, the Theory vs. Empiricism Ignite session was a goldmine for quotes:

“In God we trust, all others bring data” (H. Edwards Deming)

“Models are our only hope” (Greg Dwyer)

"Nature represents a special part of parameter space" (Jay Stachowicz)

The Theory vs. Empiricism Ignite session was designed in response to an impromptu survey at ESA last year that found that 2/3 s of an audience did not believe that there are general laws in ecology. Speakers were asked to choose whether an empirical paper or a theoretical paper would be most important for ecology, and to defend their choice, perhaps creating some entertaining antagonism along the way. 

There wasn't actually much antagonism to be had: participants were mostly conciliatory and hardly controversial. Despite this, the session was entertaining and also insightful, but perhaps not in the way I expected. First though, I should say that I think the conversation could have used some definitions of the terms (“theory”,  “empiricism”). We throw these terms around a lot but they mean different things to different people. What counts as theory to a field based scientist may be consider no more than a rule of thumb or statistical model to a pure theoretician. Data from a microcosm might not count as experimental evidence to a fieldwork-oriented ecologist.

The short talks included examples and arguments as to how theoretical or empirical science is a necessary and valuable contributor to ecological discoveries. That was fine, but the subtext from a number of talks turned out to be more interesting. The tension, it seemed, was not about whether theory is useful or empiricism is valuable, but about which one is more important. Should theory or empiricism be the driver of ecological research? (Kudos to Fred Adler for the joke that theory wants to be a demanding queen ant with empiricists as the brainless order-following workers!) And funding should follow the most worthy work. Thus empiricists bemoan the lack of funding for natural history, while theoreticians argue that pure theory is even harder to get grants for. The question of which one should lead research was sadly mostly unanswered (and 5 minutes per person didn't offer much space for a deeper discussion). 

Of course there was the inevitable call for reconciliation of the two areas, of some way to breach the arrogance and ignorance (to paraphrase Brad Cardinale) holding them apart. Or, perhaps all ecologists should be renaissance scientists, who have mastered theory and empiricism equally. Hard to say. For me, considering the example of ecological subfields that have found a balance and feedback between theory and data is wise. Areas such as disease ecology or population biology incorporate models and experiments successfully, for example. Why do some other fields like community ecology or conservation biology struggle so much more?

#ESA2014 - Day 3 bringing together theory and empiricism

I was tied up in a session all afternoon, so most of the interesting comments below are from Topher Weiss-Lehman, who caught what sounds like a pretty thought provoking session about theory and conservation biology, with thought provoking talks from Hugh Possingham and David Ackerly. This concept of bringing theory and empiricism together permeated through a number of talks, including the session I moderated on using microbes in theoretical ecology and applying theory to microbial ecology (although at the moment, the distance between those things still feels large).

The most thought-provoking talk I saw was Peter Chesson's, on "Diversity maintenance: new concepts and theory for communities as multiple-scale entities". Chesson discussed his discomfort with how his coexistence theory is sometimes applied (I suppose that is the definition of success, that you see your ideas misused). His concerns fall with those of many ecologists on the question of how to define and research an ecological community. Is the obsession with the looking at 'local' communities limiting and misguided, particularly when paired with the ridiculous assumption that such communities are closed systems? Much like Ricklef's well known paper on the defining a 'regional community', Chesson suggests we move to a multi-scale emphasis for community ecology.

Rather than calculating coexistence in a local community, Chesson argued that ecologists should be begin to think about how coexistence mechanisms varied in strength across multiple spatial scales. For example, is frequency dependence more importance at smaller or larger scales? He used a concept similar to the idea of Ricklef's regional community, in which a larger extent encompassed a number of increasingly smaller scale communities. The regional community likely includes environmental gradients, and species distributions that vary across them. Chesson presented some simulations based on a multi-scale model of species interactions to illustrate the potential of his multi-scale coexistence theory framework. The model appears to bring together Chesson's work on coexistence mechanisms-- including the importance of fitness differences (here with fitness calculated at each scale as the change in density over a time step) and stabilizing forces, and the invasion criteria (where coexistence has a signal of a positive growth rate from low density)--and his scale-transition theory work. This is a very obvious advance, and a sensible way of recognizing the scale-dependent nature of ecology in coexistence mechanisms. His approaches allows ecologists to drop their obsession with defining some spatial area as "the community" and a regional community decreases the importance of the closed system assumption. My one with is that there be some discussion of how this concept fits with existing ideas about scale and communities in ecology. For example, how compatible are existing larger scale approaches like macroecology/biogeography and other theoretical paradigms like metacommunity theory with this?  

#Notes from Topher Weiss-Lehman

Applied Theory I spent the morning of my third day at ESA in a symposium on Advancing Ecological Theory for Conservation Biology. Hugh Possingham started out with a call for more grand theories in a talk titled “Theory for conservation decisions: the death of bravery.” Possingham argued for the development of theory tailored to the needs of conservation managers, identifying the SLOSS debate as an example of the scientific community agonizing over the answer to a question no managers were asking. He described the type of theory he meant as simple and easily applicable rather than relying on intensive computer simulations that managers are unlikely to be able to use for their own systems. Possingham is right that conservation managers need theory to help guide them in decisions over where and what species to protect, however I can’t help but think about the scientific advances that arose specifically as a result of the SLOSS debate and computational models. The talk left me wondering if theoretical ecology, like other scientific fields, could be split into basic and applied theory.

The other talks in the session approached the topic of theory for conservation from a number of perspectives. Justin Kitzes discussed the ways in which macroecology can inform conservation concerns and Annette Ostling explored how niche and neutral community dynamics affect extinction debts. H. Resit Akakaya provided a wonderful example of the utility of computer simulations for conservation issues. He presented results predicting the extinction risk of species due to climate change via simulations based on niche modeling coupled with metapopulation dynamics. Jennifer Dunne then explored how the network structure of food webs changed as a result of human arrival and hunting in several systems. The session ended with a presentation by David Ackerly calling for a focus on disequilibrium dynamics in ecology. Ackerly made a compelling case for the importance of considering disequilibrium dynamics, particularly when making predictions of species reactions to climate change or habitat alteration. However the most memorable part of his talk for me was the last 5 minutes or so. He suggested that we reconsider what conservation success should mean. Since systems are changing and will continue to change, Ackerly argued that to set conservation goals based on keeping them the way they are is setting ourselves up for failure. Instead, we need to understand that systems are transitioning and that while we have a crucial role in deciding what they might transition into, we can’t and shouldn’t try to stop them from changing.

The talks today gave me lots of ideas and new papers to read, but they also left me pondering more questions on the philosophy of science (what we do, why we do it, and what our goals should be) than I expected.

#ESA2014: Day 1, just getting started

First off, apparently I wrote that I would be 'live blogging ESA'. Actually, all that means is that, I'm alive, I'm blogging, and I'm at ESA. :-)

Secondly, several other people will be giving snippets from their days this week, including Lauren Shoemaker, and Geoff Legault (below).

The first day is always more about the experience than the content: you are often lost, have no firm idea of where you need to be, and are constantly running into friends and acquaintances. It's great, but not conducive to settling into talks.

For that reason, I'll just mention the experiences that I found most exciting today. First, I saw a number of Ignite talks. These are a recent addition to ESA and are basically 5 minute talks using slides that advance every 15s. This requires a certain ability on the part of the speaker to be brief and yet informative, minimalist but not inaccurate, practiced, but not robotic. I thought that many of the speakers in the Ecosystems in the Third National Climate Assessment achieved this. One speaker, Linda Joyce said -  "if you want to feel like a graduate student again, sign up for an Ignite talk." Presumably because it makes you feel nerves like you haven't felt in years!

Joyce gave a great talk, as did others. Some of the conversation around the ecosystem assessment fell into the discourse that ecosystems provide services, and services imply people. Are ecosystem assessments only about people? Obviously this is too challenging a topic for a 5 minute talk, but it certainly sparks to further discussion on the topic, as it was meant to.

The second session of interest to me was an organized symposium in which early career scientists gave talks about their work. The central thread was simply that all of the speakers were pre-tenure academics. This really worked as a theme to tie the session together. At the end, the speakers answered questions briefly about their careers, advice, and research. Their best advice was really very good, if in line with what you here on attempting a job in academia. Find mentors. Set boundaries between your personal and private life. Say no sometimes, if it means maintaining some sort of sanity (e.g travel less, have more time with your family). A point that came up multiple times was simply, you have to have passion for science, have to love talking about your work. Having something you're passionate about is better than having ten things you are lukewarm on. And always find people to collaborate with, to talk with, to support.

Finally, there are many paths to success. And failure is universal, but not final.

(My favourite quote - someone who mentioned measuring effort in 'undergraduate work hours')

#Lauren Shoemaker

ESA had some excellent talks to start the 99th conference in Sacramento, California. I stayed in Community Assembly and Neutral Theory for several talks before running back and forth between the Hyatt, Sheraton, and conference center (missing the first few minutes of several talks).

In Community Assembly, Maria Stockenreiter gave a fantastic talk on community assembly in phytoplankton communities while building on the theory of Miller et al. (2009) examining the role of unsuccessful invaders in shaping communities. Even unsuccessful invaders within a community can alter environmental conditions or species distributions such that an unsuccessful invasion can exclude a current or future potentially successful invader. Maria tested this theory using two phytoplankton communities—a lab strain with no shared ecological history and a Gull lake community with shared history. While all invaders were unsuccessful in the experiments, they had large effects on community diversity. Unsuccessful invasion decreased diversity in the lab strains but increased diversity in the Gull Lake community, showing both the “ghost effect” of competition and the role of shared ecological histories.

In Paleoecology, Matthew Knope examined the functional diversity-taxonomic diversity relationships for marine animals during the past 500 million years. It was fun to think of a relationship I only consider in current-times over such a long timescale. Matthew categorized marine mammals according to their location in a discrete 3-dimensional niche space (tiering on sea floor, feeding mode, and motility). The data show that the amount of functional diversity was far lower than expected based on taxonomic diversity until only recently. Additionally, I was amazed to see a consistent trend (from 3 different mass extinctions in the dataset) that mass extinctions promote functional diversity 10-20 million years post extinction leading to even higher functional diversity than pre-extinction.

Back at the convention center in the Biodiversity I session, Pascal Niklaus examined if interspecific vertical canopy space partitioning promoted productivity in subtropical forests. While light is a directional resource, creating a large advantage for being tall, Pascal found that vertical niche partitioning still occurred when comparing monocultures to multiple species assemblages. Species in higher diversity communities also had narrower niches, and similar species shifted their vertical leaf biomass niche, but only in shaded treatments. Vertical niche partitioning did, indeed, promote higher ecosystem function.

#Geoff Legault

I arrived in Sacramento this afternoon so I did not get a chance to see many talks (though I did enjoy Meghan Duffy’s talk about possible hydra effects in Daphnia). I did, however, see a number of excellent posters, particularly one by Nick Rasmussen on the interactive effects of density and phenology on the recruitment of toads. I was impressed by his use of mesocosms to directly manipulate these factors and found that he made a compelling case for the idea that the degree of synchrony in hatching can determine which form of intraspecific competition dominates recruitment.

#ESA2014 : Getting ready for (and surviving) ESA

There is less than one week until ecology's largest meeting. ESA's annual meeting starts August 10th in Sacramento, California, and it can be both exciting and also be overwhelming in its size and scope. Here are a few suggestions for making it a success.

Getting ready for ESA.
Sure, things start in a week and you're scheduled for a talk/poster/meeting with a famous prof, but you haven't started preparing yet.

First off, no point beating yourself up for procrastinating: if you've been thinking about your presentation but doing other projects, you might be in the company of other successful people.

If you're giving a talk, and given it before or are an old hand at this sort of thing, go ahead and put it together the night before your talk. One benefit for the truly experienced or gifted speaker is that this talk will never sound over-rehearsed.

Regardless, all speakers should try for a talk that is focused, with a clear narrative and argument, and within the allotted time. (Nothing is more awkward for everyone involved than watching the moderate have to interrupt a speaker). The good news is that ESA audiences will probably be a) educated to at least a basic level on your topic, and b) are usually generous with their attention and polite with their questions. This blog has some really practical advice on putting together an academic talk.
If at all possible, practice in front of a friendly audience ahead of time.

The questions after your talk will vary, and if you're lucky they will relate to future directions, experimental design, quantitative double-checks, and the truly insightful thoughts. However, there other common questions that you should recognize: the courtesy question (good moderators have a few in hand), the "tell-me-how-it-relates-to-my-work" question, and the wandering unquestion.

Giving a poster is much different than giving a talk, and it has pros and cons. First, you have to have it finished in time to have it printed, so procrastination is less possible. Posters are great if you want one-on-one interactions with a wide range of people. You have to make your poster attractive and interesting: this always means don't put too much text on your poster. The start of this pdf gives some nice advice on getting the most out of your poster presentation.

For both posters and presentations, graphics and visual appeal make a big difference. Check out the blog, DeScience, which has some great suggestions for science communication.

Academic meetings. These run the gamut from collaborators that you're just catching up with, to strangers that you have contacted to meet to discuss common scientific interests. If scientists that you share common research activities and interests with are attending ESA, it never hurts to try to meet with them. Many academics are generous with their time, especially for young researchers. If they say yes, come prepared for the conversation. If necessary, review their work that relates to your own. Come prepared to describe your interests and the project/question/experiment you were looking for advice on. It can be very helpful to have some specific questions in mind, in order facilitate the conversation.

What to wear. Impossible to say. Depending on who you are and wear you work normally, you can wear anything from torn field gear and binos to a nice dress or suit (although not too many people will be in suits).

Surviving ESA.
ESA can be very large and fairly exhausting. The key is to pace yourself and take breaks: you don't need to see talks all day long to get your money's worth from ESA. Prioritize the talks that you want to see based on things like speaker or topic. Sitting in on topics totally different from those you study can be quite energizing as well. In this age of smartphones, the e-program is invaluable.

Social media can help you find popular or interesting sounding talks, or fill you in on highlights you missed. This year the official hashtag on twitter is #ESA2014.

One of the most important things you can do is be open to meeting new people, whether through dinner and lunch invites, mixers, or other organized activities. Introverts might cringe a little, but the longest lasting outcome from big conferences is the connections you make there.

Eat and try to get some sleep.

**The EEB & Flow will be live-blogging during ESA 2014 in Sacramento, as we have for the last few years. See everyone in Sacramento!**

#esa2013 What ESA tells us about where ecology is going

The annual ESA meeting functions in a lot of different ways. There are the obvious: the sharing of ideas and work, the discovery of new ideas, methods or sources of inspiration, networking and job finding, social reunions. But it also functions as a kind of report on the state of the field (and that's not even considering sessions meant to explicitly do this, like the panel “Conversations on the Future of Ecology”). The topics and methods presented say a lot about what ideas and methods are timeless, what is trendy, and over many meetings, where ecology appears to be going. If you go to enough ESAs, you are participating in a longitudinal study of ecology (or at least your subfield).

I went to my first ESA five years ago in Albuquerque, NM. One of the things that struck me was that there were two Community Assembly and Neutral Theory sessions and many talks in those focused on tests of neutral theory, particularly looking at species abundance distributions (SADs) and various iterations of neutral models. There are usually still one to two sessions called Community Assembly and Neutral Theory, but five years later, I don't think I saw a single talk that looked at SADs for evidence of neutral theory (and only one or two talks that were named to explicitly include neutral theory). Instead, the concept first introduced by Hubbell has morphed from "neutral theory" in to something slightly more general, designated "neutral dynamics". This gets used in a lot of ways – most precisely, neutral dynamics are in the spirit of neutral theory, suggesting that population demographic rates are similar, allowing long-term co-occurrence. Sometimes this is cited with reference to equalizing fitness effects in a Chessonian framework, where similarity in fitnesses prevents exclusion despite overlap in species niches. But it also seemed to get used in a default sort of way, as the explanation for why niche differences between species weren't discovered by a study, or else "neutral" was used interchangeably with "stochastic". In any case, the pattern appeared to be a move from highly specialized and precisely defined usage of the term, to broader incorporation of the concept that had suddenly acquired several, often less precisely defined meanings. Instead of being the central focus of a few specialized talks, neutrality was commonly invoked as a minor theme or explanation in many more talks. It is not what I expected, but its continuing usage suggests that neutrality has developed a life of its own.

Other topics similarly seem to have taken on separate lives from their initial application; even over the short time I've been attending ESA. For example, sessions focused on simple applications of ecophylogenetics methods (overdispersion, clustering, using different systems) were relatively common 3-4 years ago, while there wasn't a single contributed session specifically named for phylogenetics this year. There was however many sessions in which phylogenetic work formed the backbone of talks that were about broader questions, including in the "Evolution, Biodiversity, and Ecosystem Function" session and the “Coexistence of Closest Relatives: Synthesis of Ecological and Evolutionary Perspectives”. In the best case scenarios, it seems like even over-hyped approaches may be used with more nuance in time, as people recognize what information these methods can and cannot provide.

Sometimes it did seem that there is a lag between when critiques of certain methods or ideas are expressed and when they actually get incorporated into research. I could be wrong, but it seems this is most common where the research is focused on particular study systems or species, and methodology may be driven more by precedent in the literature and criticisms may take longer to infiltrate (since they aren’t the main focus of the work anyways). And unfortunately, the topics and sessions which appear to be timeless are those on human-related applications (restoration, climate change, invasion). Those pressures are sadly unchanging.

*The great thing to do would be map out changes in keyword frequency over the ESAs that have archived programs. Unfortunately, I don’t have the time/motivation.

#esa2013 Day 5: Survival mode

The final day crowd is usually a little worse for wear. 

(Adapted from phdcomics.com)

#esa2013 Day4: Sisters getting along, and our variable world

The talks I saw today were uniformly good and a number were excellent. At least half of them focused on the many implications for ecology of nature's innate variability. It appears that community ecologists have decided that now is the time to start considering the fact that the environment is not stationary, which was long a default assumption in most theoretical and empirical work. Many of the talks I saw reflected this changing approach. The other half were part of a symposium organized by Sharon Strauss that looked at coexistence among sister species. This topic, combining as it did large-scale evolutionary and biogeographic processes with local competitive interactions made for a broad range of talks and some interesting attempts to reconcile different methodologies and scales.

Our variable world

Many of the past studies on environmental variability and coexistence involve desert winter annuals. Desert winter annuals are limited by available water, and the yearly rains vary greatly in the amount and timing of onset. The hypothesis is that variable germination (via prolonged dormancy in seedbanks) may allow desert winter annuals to reduce the variance in their fitness between years. Alejandra Martinez-Berdeja presented some tidy hypothesis testing using biogeographical gradients: if variable germination is an adaptive response to variable precipitation, she hypothesized that differences in germination variability might be expected where precipitation is more or less predictable. Looking at the three North American deserts, she predicted that variable germination would be greater where rainfall was more variable (bi-seasonal) compared to winter rainfall deserts. She measured the involucres (dispersal structures determining seed release) on collected seeds and found that indeed they were larger in more variable rainfall deserts, producing greater variability in seed release. Further, in winter rainfall deserts, variability in the size of involucres was correlated with variability in rainfall at a site, again suggesting a link between germination variability and rainfall variability. Her next step will hopefully be to expand the tests look at the effect of autocorrelation in rainfall likelihood on bet-hedging, since this should increase selection for bet-hedging type adaptations.

David Vasseur gave a great talk showing how extreme environmental conditions--which we are seeing as part of the changes in mean and variance of the climate--could have particularly detrimental effects on population growth rates. Species have temperature performance curves that reflect the relationship between their fitness and the temperatures they experience. Vasseur showed that in the tropics, species tend to have much narrower temperature ranges over which they can grow and survive than species in the temperature regions, and experts agree that these narrower curves give tropical species less ability to deal with increasing temperatures. But variability is rarely considered in this equation. When variability is present, long-term species fitnesses will be subject to Jensen's inequality (nonlinear averaging) mean that shape of these performance curves is additionally important: that in some situations (concave curves) variability is particularly detrimental, and in some situations (convex curves) it may have a beneficial effect. Vasseur then used models to show that as temperature variation increases, it is increasingly likely that its effect will be negative, and high variation will produce high extinction rates. In fact, on average Vasseur predicted that temperature variation would have negative effects, a concerning conclusion.

Sisters getting along

This organized symposium was advertised as: “Whether closest relatives coexist reflects the often opposing effects of limiting similarity, mode of speciation, reproductive isolation, niche conservatism, competition and facilitation, which may be strongest in sister taxa; using new phylogenies, niche models, and experimental approaches, we explore coexistence in closest relatives in both plants and animals.” It was an interesting and useful idea – sister species (species who are each other’s most recent relative) are an important tool to understand how evolution, biogeography, and ecological interactions determine coexistence. The content of the symposium provided a number of example systems, methods, and approaches that suggested this was an important but still far from cohesive area of work. Mark McPeek spoke about the damselfly work he has done over the last many years, which shows that sister species are sympatric and ecologically identical, co-occurring happily through neutral dynamics. In contrast, Richard Glor talked about his work with Hispaniola anoles, where biogeography is an explanation for radiations, close relatives use different microhabitats and rarely compete locally and traits are divergent among close relatives. Looking at California plant species, Brian Anacker’s talk suggested something in between these extremes. A broad survey showed that 80% of sister pairs were sympatric, range overlap was modest but not uncommon, but asymmetry in range size was high. Ecological differences between sister species were not particularly clear in the handful of traits he examined, not even for reproductive traits. Sister species can and do co-occur, although not in large portions of their ranges. Having established the current state of knowledge, hopefully the symposium will stimulate greater focus on the construct of sister species as a way of understanding coexistence at multiple scales.

Finally, not being willing to miss another talk with the word “derby” in the title, I attended Daniel Atwater’s talk, “Is competition among plants like a boxing match or a demolition derby? Why competitor suppression may not matter in plant communities”. Atwater argued that there were two ways to win at plant competition – be good at suppressing your competitors, or be good at tolerating them. When in competition with a single individual, being a strong suppressor should be favoured, but in competition with multiple species, tolerance may be a better strategy. That’s because resources spent on suppressing one competitor may also benefit any other species involved in the competition. In such cases, tolerance of your competitors may provide the greatest benefit. (Apparently this scenario is like a successful (but frowned upon) strategy (sandbagging) in a demolition derby). Atwater used experimental data from blue bunch grass grown in competition with spotted knapweed to parameterize a model in which he found the optimum strategy in single versus multi-species competitions. The model agreed with his hypothesis that tolerating competitors is favoured when multiple species are competing. Although I am not clear on whether competitive strategies are easily classified as tolerant vs suppressing it was an interesting talk, and left me thinking about new questions.

ESA 2013 Day 3: Bolkerisms

All the best quotes that I caught today were undeniably from Ben Bolker, who also gave an interesting talk.

"The hallmark of great theoretical ecology is that it is obvious in hindsight. When you explain it to someone, they say well, of course."

In relation to a philosophical issue: "That's a beer question, not a coffee question".

To explain the reason he and his coauthors chose to build a model to explore the question, Bolker showed a Dilbert cartoon illustrating the truism "When all you have is a hammer, everything looks like a nail".

Only one full day left to go, and it looks like it will be a good one!

ESA 2013, day 3: Like a kid in a candy store.

Sometimes there are moments in my career where feel truly fortunate. Today I was fortunate enough to be a speaker in a session on evolution, biodiversity and ecosystem function. The other talks in this session were outstanding, full of amazing insights into how historical evolutionary dynamics affect modern-day ecological patterns. The presentations were followed by a fantastic panel discussion stimulated by thoughtful questions from the audience. The talks covered a range of topics from including species interactions in models of evolutionary change to using traits to understand coexistence to trying to find patterns when close relatives do not coexist.

The first talk from Luke Harmon on finding phylogenetic signatures on species interactions was incredible. He is an entertaining speaker and included references to his kids finding leaf cutter ants.  He show us how one could fit phylogenetic models that include coevolution. The negative effects of coevolution should affect trait evolution and one should see this signature in variance-covariance matrices. Random evolutionary change generates covariance between species. Stabilizing selection will remove this covariance, while with competition there should be negative covariances apparent. From models we see an interesting signature where older species are able to diverge and fill niche space (thus diverging rapidly) while later species are constrained in their evolution (thus remaining similar). Older species can contribute more to ecosystem function because of historical competitive effects.

Next was Nathan Kraft talking about how traits can potential shed light on fitness and niche differences in coexisting species. In a plant experiment with focal species grown alone and at different densities with competitors, he showed that very few pairs met the conditions for coexistence. For those that do appear to be able to coexist, no traits were associated with fitness difference, but several traits appeared to be associated with fitness differences. Multivariate analyses  showed that an assortment of five traits collectively appeared to be associated with niche differences. Some of these traits appeared to also explain fitness differences, revealing the complexity in assigning traits to specific ecological effects.

In Jeannine Cavender-Bares’ talk, she examined how evolutionary transitions in seed dormancy helped explain modern day ecological patterns in the Fabaceae family (the pea and bean family). The Fabaceae includes species that have dormant and non-dormant  seeds. Dormancy should be favored in certain environments (e.g., less predictable and poor environments). Large seeds are much less likely to be dormant, as well as those occurring at lower latitudes. Historical transitions in dormancy seemed to be correlated with changes in temperature lineages experienced.

Finally, Sharon Strauss critically examine dhow to separate history form ecology. We need to be cognizant of scale effects, where larger scale observations will include more close relatives than we usually see at local scales. Communities contain ‘ghosts’ of past competition and assembly. If species originate allopatrically (in separate places), then we expect that close relatives should not coexist, which can skew our inference about how ecological differences have evolved. Within habitats we seldom see closely related species coexisting . She gave a number of great Californian examples of species appearing to co-occur at large scales but not locally. For example, Limnanthes plants occur in the same region but species never co-occur in the same vernal pool.

These talks represent the collective excitement about the fact that we are entering a new synthesis in ecology. Evolution is required to understand ecological patters and ecological interactions are need for understanding evolutionary change. These talks exhibited where the forefront of this synthesis is, and it was a great afternoon of talks.

ESA Day 2: The problem with statistics...

These are just my favourite quotes from talks on day two of ESA:

(All from great, but anonymous, speakers)

After showing the results of a spatial statistics test: "...But still I was worried because that would be using statistics to prove something and that feels wrong."

On being asked how the speaker quantified earthworm abundance: "I used a non-invasive electroshock technique".
(I'm sure this is normal procedure, it just sounds hilarious to the uninformed).

ESA day 2: The shampoo salesman and new questions.

Day two started off on a high note with Bernhard Schmid's talk on evolution in biodiversity-ecosystem function (BEF) experiments. He is one of the originators of the Jena biodiveristy experiment, for years they have been maintaining plant species in monocultures and in polycultures to assess how much more ecosystem function is produced by multi-species assemblages over single species monocultures. However, it occurred to Schmid that species in these two contexts face different pressures, which may have resulted in evolutionary changes. In monocultures, species face high intraspecific densities and thus competition is severe, as is negative indirect effects like pathogen sharing and herbivory rates. Within polycultures, intrraspecific interactions may involve niche differences, with opportunities for character divergence to further stabilize coexistence. He reported on an experiment that took seeds and cuttings from monoculture and polyculture populations and grew then in monoculture or polyculture. He showed that individuals originating from monoculture did better in monoculture and species originating from polyculture did better in polyculture. The implications are fascinating. If the rate of evolutionary change in performance are equivalent between monocultures and polycultures, the BEF relationships should remain constant. However, if the rates of change are greater for polyculture populations the BEF relationship should get stronger over time. Conversely, BEF relationships should became weaker if higher evolutionary change in monoculture. 

It was hard to top this talk, but there were several other impressive talks as well. Jacob Vander Laan used a country-wide dataset on aquatic insect diversity across the USA and showed that at larger scales, beta-diversity decreases with connectivity, but is seemingly unaffected by environmental heterogeneity.

Restoration is community assembly with management goals and Emily Grman gave an interesting talk on assessing the success of prairie restoration by accounting for management activities, landscape, historical and local abiotic factors. She showed that management activities were the most important, with species-rich sowings result in rich communities, even though many of the species are not those in the sown mixture. Sowing a high diversity of grasses did not increase diversity, but high diversity of forbes did. Other factors like landscape influences and local factors were not important.

Will Pearse examined plant diversity patterns and homogenization across six large urban centres. He showed that there has been little taxonomic homogenization, but substantial phylogenetic and moderate functional trait homogenization. Beyond the interesting questions about how urban centres may cause biotic homogenization is the new tools that Pearse created for these analyses, and that are available online. As a self described 'shampoo salesman', he created a general tool called Phylogenerator that creates a pipeline that makes estimating trees form sequence data more efficient -definitely a tool that ecologists should be using. He further created a way to quantify complex leaf shapes and has a tool available for that, called Stalkless.

All in all , this was a good day, one that has stimulated new questions and approaches. These talks got me thinking about some of my data and experiments and how I can extend them to new questions. 

ESA 2013 Day 1: Temporal variation, roller derby, and topics in between

With day 1 over, ESA 2013 was off to an excellent start. Minneapolis seems like a very friendly place, and I enjoyed perhaps the most chatty bus ride I've ever experienced. As always, I failed to determine the best point on the trade off plot between cherry-picking certain talks based on topic, speaker and friends, and staying put in a session with an interesting topic. Nonetheless I managed to see some really good talks.

Among them, I saw Lauren Shoemaker in the Theoretical Ecology section, who illustrated how to model the four metacommunity paradigms (I.e. species sorting, mass effects, neutral, and patch dynamics) with the Chessonian framework of equalizing and stabilizing forces. She illustrated how both deterministic and stochastic models could replicate dynamics from the four paradigms. This suggests that rather than the usual description of the neutral paradigm as stochastic and the mass effect and species sorting paradigms as niche-based and therefore deterministic, the terms niche and deterministic and neutral and stochastic should not be synonymous. Rather, in the Chessonian framework, fitness differences drive neutral-type dynamics and spatial niches structure the species sorting and mass effects paradigms. More importantly, the results show how the paradigms are just a few sets of points on the much broader set of parameter values that could describe metacommunity dynamics.

It must be funny for Peter Chesson to follow up a talk in which his name is used as an adjective. After the talk on the Chessonian framework, he spoke about the fact that environment is fluid and non-stationary, yet models of communities have almost always treated it as being at equilibrium. Since it is not, ideally models of community dynamics would begin to incorporate environmental variation, and ask questions more relevant to non-equilibrium systems. For example: when is long-term persistence expected, given this non-stationarity and can communities in a non-stationary system still be stable? He showed that including environmental fluidity into models doesn't mean that communities are necessarily unstable, for example, when spatial and temporal trends of environmental variation match, communities may be stationary.

In another of many good talks about temporal variation (seemingly a popular topic of late), Colin Kremer showed that altering the basic characteristics of abiotic temporal variation (amplitude, means, periodicity) changed the amount of diversity present as communities evolved over time. Temporal variation isn't a simple concept anymore than spatial variability is - it has different characteristics with different effects on ecological dynamics and needs to be considered in greater depth.

My biggest disappointment was that I had a time conflict and couldn't attend a talk titled "Significant changes in the skin microbiome mediated by the sport of roller derby".  No doubt I would have learned a lot.

Things I've learned at ESA this year

1. It's more useful to talk to people than it is to be an audience member.
2. A successful talk is one that produces interactions with people.
3. The grass is not always greener- the talk you missed was probably not as great as everyone is saying anyways (actually it probably was, but it's too late now...)
4. Picking only specific talks and people to hear can be a good strategy for avoiding talk burnout. Symptoms of talk burnout include napping in conference centre hallways, feelings of annoyance when you hear the same concept re-explained for the 10th time (which is probably because you're in the 7th Community Patterns and Dynamics session), and a desire to yell 'but what is your hypothesis?!' during talks (this may just be me). The only cure for this is to go have a drink.
5. Conversely, sitting through entire sessions can lead to important discoveries.
6. There are more areas of research in ecology than you can list: by bringing these researchers together, ESA is helping to foster continued growth in our field. Integrating all these bodies of knowledge is important if ecology is to be a healthy, mature discipline.


08/10/6:50, edited for clarity. #7 could be 'it's better not to blog while tired'.

ESA day 3: a meeting of meetings

Wednesday was a crazy day, bouncing between talks and one-on-one meetings. This is what ESA is about: connecting with friends and colleagues, and seeing exciting new science. There were a bunch of fun talks that introduced new ideas and concepts, or made connections between different approaches. Some of these talks included Dylan Craven, who linked plant functional traits to performance in secondary successional forests in Panama. In Nicholas Gotelli’s talk, he tried to reconcile thousands of museum ant records with ecological surveys to estimate abundance, distribution and numbers of ant species in the north east USA. Sam Scheiner discussed a new approach to combine phylogeny and traits at the community level.

There were also some talks that seemed to really resonate with me, and the audiences attending them. Katherine Richgels gave a very interesting talk on trematode metacommunities, where the primary patches (snails) live in other patches (ponds). The primary patches have unique dynamics, including movement. The environment and host abundance seem to strongly determine trematode community patterns.

Bruce Menge astounded his audience with a new hypothesis: the ‘intermittent upwelling hypothesis’ which states that ecological process rates should be maximized at intermittent upwelling coastal zones. He ran experiments on coasts around the world and showed that recruitment, herbivory and predation rates were all maximized when upwelling was intermittent.

Cecil Albert showed how a model can predict the effects of global change and landscape alteration. She used a ‘sandwich’ modeling approach, where vegetation structure is sandwiched between climate change influences at large scale and landscape change at smaller scales. The resulting vegetation changes can be used to predict responses from specific indicator species or ecosystem function. She then showed how different scenarios of landuse change (random habitat removal, zoning and protecting corridors) can result in different responses in indicator species.

Finally, Caroline Tucker* gave a great talk on the effects of global warming on changes in flowering time in competitive communities.  Most people assume that plants will flower earlier in a warmer world, but these predictions ignore competitive effects. Using a set of linked growth and phenology models, she showed that indeed plants increase growth and flower earlier with warming in the absence of competition. However, once you allow the species to compete, the advance in flowering time is unequal. Early species, which are generally released from competition will flower earlier. So too will late species which tend to be good competitors. However, intermediate species do not advance their flowering due to competition.

*Yes this is our Caroline Tucker.

**Caroline has been on me to post my Wed. talk summary for two days.

ESA 2012: Day 4

 For some reason, Day 4 had many talks I wanted to see, just when the effects of late nights and over-caffeination were starting to peak. The reward to remaining awake through a day of talks was that I got to hear some excellent ecology.

At 8:20 (yes, 8:20) in the Biodiversity III session, Xubing Liu spoke about some of the work his research group is producing to expand our understanding of the Janzen-Connell effect. (For a good example of this work, see http://onlinelibrary.wiley.com/doi/10.1111/j.1461-0248.2011.01715.x/abstract). The Janzen-Connell effect is a density-dependent mechanism in which proximity to individuals of the same species increases their chance of encountering species-specific predators or diseases, and therefore reduces their chance of survival. This is hypothesized to produce coexistence by maintaining lower abundances and higher diversity. In this talk, Liu explained how intraspecific variation could similarly be maintained via a Janzen-Connell effect. He showed experimentally that decreasing the degree of relationship between two individuals of the same species (increasing intraspecific diversity) increased their odds of surviving fungal infection. Such a mechanism could help explain how intraspecific variation is maintained, which is a hot topic these days.

A talk I found particularly interesting, perhaps because it was so different in content and style from my own work was that by Robert Beschta from Oregon State University. He convinced me, without statistics or plots, that the outcome of a natural experiment – the removal of apex predators from America’s park system – was highly detrimental to those ecosystems. Removal of wolves and cougars from National Parks such as Yellowstone and Olympia have produced many changes in community structure and function – the understory disappeared as deer and elk browsed all young greenery, river edges eroded without shrubbery, and forests aged. Yellowstone provided an additional validation to this conclusion; re-introducing wolves appears to be producing gradual reversion to more diverse and functional habitat.

Diane Srivastava further provided the type of perspective only gained from years of research. She also illustrated that the contribution of a body of work is often more than the sum of its parts. Diane has spent 15 years of studying a bromeliad system in which multiple invertebrates live in the water collected in the plants, forming a complex ecosystem with multiple trophic levels. The data collected over this time allowed her to perform a meta-analysis which shed more light on the dynamics of this system than any individual study allowed.

There were multiple talks from students of Peter Chesson, an eminent theoretician, and all shed light on mechanisms of coexistence. Although perhaps too complicated to explore in a short summary, they covered topics in keeping with other work from the lab, especially the role of temporal and spatial variability in driving fluctuations in recruitment and ultimately coexistence, and in understanding how mechanisms will scale with space. His students were well informed on the intricacies of Chessonian theory and the talks certainly created lots to think about.

Finally, two talks discussed the growing problem of reconciling trait- and phylogenetic-based community ecology. Rebecca Best presented the results of a amphipod competition experiment, in which she examined whether feeding traits or phylogenetic distances were a better explanation for the resulting diversity and abundances. She found, as is not uncommon, that traits were by far more useful in understanding the amphipod community. She didn’t stop there, however, and tested further how the phylogeny and trait values actually related – it turned out that traits and phylogeny were not correlated, and represented different mechanisms at play in the species' ecologies. Though she found that phylogenies could not predict the outcome of her community experiment, she concluded that this didn’t mean that phylogenies were not important, only that they were important at different scales or in different mechanisms then she had been focusing on.

Finally, a talk directly relevant to Best’s work came from the EEB & Flow’s Marc Cadotte. Since it was a well-received and interesting talk, I feel like giving his talk a plug here isn’t too biased. Cadotte presented a metric meant to incorporate both trait and phylogenetic information, and further to incorporate them in a meaningful way. Name FPDist (for functional phylogenetic distance), this metric incorporates an additional axis (functional diversity): this can be represented with a phylogenetic tree in which the x-axis represents trait distance and the y-axis phylogenetic distance. This allows you to visualize trait divergence and convergence in a way that traditional trees cannot. Further, the metric he presented is a function of both traits and phylogeny, combined in such a way that the relative importance of each can be captured and recognized. This allows us to more fully investigate both traits and phylogeny contribute to community diversity. No doubt an interesting paper will follow soon.

Off to survive one more night and one more morning.

EEB & Flow Portland bound

Just a heads up that Marc Cadotte and I will be live blogging the Ecological Society of America's Annual Meeting in Portland, from Aug. 6-10th. As always, this is a great chance for ecologists to hear about great science and run into old and new friends. If you see Marc Cadotte there, be sure to harass him to post on time, as he claims to be 'busy' ;)

Day 5 in Austin

The ecological community in Austin assembled for the final morning of talks today, and despite the advanced stage of the conference, the 8 o’clock talk I was at was surprisingly well-attended. There was only a morning worth of talks, but frankly, the Community Pattern and Dynamics session I attended had some of the most interesting talks I’d seen all week.

I started out in the Aquatic Terrestrial Linkages section, where Tiffany Schriever introduced me to the concept of spatial subsidies (the transfer of energy from one system to another), and described her system-temporary ponds in Ontario, Canada-in which the dual aquatic and terrestrial nature of the pond amphibian and insect life cycles couple aquatic and terrestrial systems.

Although I arrived late for Rafael D’Andrea’s talk in this session, it seemed that he did an excellent job of presenting ecological models, making his question and results both clear and interesting. He examined how tradeoff models, such as Muller Landau’s seed tolerance vs. seed fecundity model, predict far less diversity can be supported when the tradeoff changes smoothly rather than abruptly.

Nathan Sanders then explained his shift from primarily place-based research to global, macroecological studies. However, Sanders acknowledged the common criticisms of the macroecological approach, in that patterns are not necessarily evidence of mechanism, and has attempted to reach a compromise between the benefits of the two approaches. To balance place-based with global approaches, Sanders and his collaborators form a global network of researchers who are carrying out the same manipulative experiments (looking at resource limitation in ants) across different systems worldwide, and the results promise to be exciting.

In the final talk in the session, Steve Walker from the Legendre lab presented his approach to dealing with the “fourth corner problem”, that is relating species traits to environmental conditions. Rather than developing new approaches for analysis, Walker has focused on approaching this problem via data management. In particular, he has developed an R package (beta available here) called multitable in which data with different dimensions (such as a site-by-species matrix and a trait-by-species matrix) can be subscripted simultaneously, and coerced into a single data frame for use in standard R functions.



All in all it was a great week, and I’m excited to get back to work and feed off the energy of the conference. ESA gave me a chance to meet some of my favourite ecology bloggers, including Ethan White and Morgan Ernest from Jabberwocky Ecology and Jeremy Fox from the Oikos blog. It made me wonder whether there might be room next year for a more formal meeting of these online colleagues, whether in a loosely organized sense, or even as a workshop or symposium focused on the how ecologists can use (and are using) new technology—especially the internet—to communicate their science. If anyone has any comments or thoughts about whether there would be a role for something like this at ESA, I'd be happy to hear them.

See you in Portland, one year from now!