Thursday, March 22, 2012

NCEAS is dead; long live NCEAS. A view towards NCEAS 2.0.

"is this a wake or revival?" Jim Brown

March 21-22, 2012, Santa Barbara, CA. National Center for Ecological Analysis and Synthesis (NCEAS) symposium.

A special invitation- only symposium marking the end of NCEAS as we know it, saw a number of interesting talks and retrospectives about where NCEAS has been and where it is going. 170 people attended, including some former postdocs, working group participants and leaders in ecology. The reason for this introspective meeting is that NCEAS's core NSF funding is about to end, without renewel. Jim Brown's quote from his talk, whether we were here for a wake or a revival really captured the spirit of the meeting.

The goals were twofold. First was to look back and celebrate the accomplishments of NCEAS. University of California at Santa Barbara is globally one the top influential research institutions in the world, and this success has been driven in large part by the success of NCEAS. More than 5000 people have come to NCEAS and their efforts have resulted in thousands of publications, and many citation classics. The early visions of NCEAS were broad and fuzzy and by all accounts NCEAS has exceeded all expectations.

The second motivation for ts meeting was to think about the future. What can NCEAS be under different funding regimes, and how should it move forward? The is no doubt that it will be fundamentally different, but can there be a successful continuation of the NCEAS model, will it die, or will it give birth to a new enerprise, NCEAS 2.0?

The symposium saw great talks, from people like Jim Brown and Jane Lubchenco, and interesting panel discussions on numerous topics (see #treas2012 in twitter for synopsis of the meeting). There were a lot of past tense statements.

However, it was clear that there was much to celebrate. NCEAS clearly impacted ecology. Did its success simply coincide with cultural changes in the field or did it drive changes? The consensus was that it drove changes. It fostered large collaborations. Dave Tilman said that before NCEAS, ecology was largely local and lab-driven, but NCEAS offered a way to get people together to ask bigger questions. The postdoctoral fellows have been extremely successful, with the vast majority ending up in faculty positions in top institutions. It was acknowledged that many sub fields were created or coalesced at NCEAS, including disease ecology and metacommunity dynamics.

Why has it been so successful? NCEAS is a special inclusive place where people want to come, away from their responsibilities. The technical help here and expertise that made anything possible, any data challenges were overcome and analytical difficulties solved. Postdocs were given complete independence and were allowed to pursue collaboration and networking. Jim Brown remarked that NCEAS is the single greatest event in the history of ecology. Subfields now talk, lab projects are now geared towards collaboration and linkages with other work in ways that did not exist before.

So then, what will the future hold for NCEAS? The answer to this was left vague and uncertain. People argued for what NCEAS 2.0 should look like. For example, it was argued that NCEAS 2.0 should resurface something like science 2.0, making the focus data and data sharing, changing methods and philosophy of how science is done. Massive anonymous collaboration requires assumed standards and altruism. Other arguments focused on the need for NCEAS to reach out to new partners and to go global.

Peter Karieva said it well. NCEAS 2.0 should be interacting with major corporations, since they represent the drastic impacts on ecological systems around the world. 1.0 was about data accessability, 2.0 should about applicability and tools to affect change.

Whatever NCEAS 2.0 looks like, it will be different. There seems to be two ways forward. One is that it struggles to maintain its past activities or one that like the Phoenix rises from the ashes and boldly goes forward to again push the ecology in new directions.

Sunday, March 11, 2012

On rejection: or, life in academia

I guess it’s not surprising, given that I’ve written about failure in science, that I would write a post about rejection as well. Actually, I’m not so interested in writing about rejection as I am in hearing how people have learned to deal with it.  

Academia is a strange workplace. It’s stocked with bright people who’ve been successful throughout their previous academic endeavours (with some exceptions*). For the most part, they haven’t faced too much criticism of their intellectual abilities. But in academia you will spend your career being questioned and criticized, in large part by your peers. You will constantly be judged (with every submitted manuscript, grant application, or tenure review). And this is the universal truth about academia: you will be rejected. And for some (many?) people, that's a difficult thing to accept.

Rejection may be so painful in part because it can be hard to interpret. After all, it’s an old trope that rejection is a normal part of academia. But how much rejection is normal, when is it just a numbers game and when is it a sign of professional failing? Let alone the fact that rejection depends on a shifting academic landscape where available funding, journal quotas, and research caliber are always changing. So I’m curious: does the ability to deal with rejection factor into academic success? Are some people, based on personality, more likely to weather rejections successfully, and does this translate into academic success? Or is the development of a thick skin just the inevitable outcome of an academic life?

*A couple of the people I know who are generally unfazed by rejections would say that they deal well with rejection because they weren’t particularly great students and so academic failure isn’t new or frightening to them. 

Friday, March 2, 2012

The niche as a changeable entity: phenotypic plasticity in community ecology

Nearly all explanations for coexistence in communities focus on differences between species. The scale of these differences may occur over large temporal (e.g. evolutionary history, phylogenetic relationships) or spatial scales (e.g. environmental tolerances), or at the scale of the individual. In plants, interactions at the local scale are given particular attention, including interactions mediated by trait differences between species. At finer scales still, there has been recent focus on differences between individuals of the same species, whether they are driven by genotypic differences (link) or plastic changes in individual phenotypes.

From Ashton et al. 2010
Phenotypic plasticity can be defined as phenotypic differences among individuals of the same genotype that occur in response to an environmental cue. The ability of plant species to alter their usage of resources, for example, has clear relevance to resource partitioning among species, since a given individual could adaptively take advantage of alternate resources in response to their particular competitive environment. In such a case, an individual’s realized niche is a function of phenotypic changes in response to the biotic and abiotic environment and thus physiologically-determined. This is in contrast to the usual approach to species’ niches, where physiological constraints are considered to determine a species’ fundamental niche. Although the plant literature shows clear examples of phenotypic plasticity among plants, including in response to competition (for example, perception of light quality leading to changes in growth form), the topic usually receives only passing mention in the community ecology literature.
The number of papers addressing questions of coexistence and competition through the lens of phenotypic plasticity is slowly rising.
From Schiffer et al. 2011, Lithium uptake is
significantly higher on the non-competitor side

A couple of papers from the last few years provide tantalizing glimpses into the possible contribution of plasticity to coexistence. In Schiffers et al. (2011), the authors use experimental and modeling approaches to test whether root uptake can change in response to the proximity of competitors. In the experimental study, the authors looked at the uptake of lithium (a stable nutrient that will be taken up in the place of potassium) by Bromus hordeaceus. They planted pairs of B. hordeaceus  at varying distances apart and then injected lithium into the soil at different differences from the focal plant. They found that lithium uptake was significantly higher on the non-competitor side of the focal plant than on the competitor side, suggesting that plastic changes in resource uptake occurred in response to competitor proximity. Modelling results from the same study suggest that plasticity may allow individuals minimize competitive pressure by making changes in belowground architecture, thereby using available space more efficiently.

Ashton et al. (2010) take a similar approach, looking at how the uptake of nutrients (in this case three forms of nitrogen (N)) varies among species depending on their competitive environment. They explored the ways in which plasticity could lead to changes in the realized niche. In particular, they explored two hypotheses: that plants would exhibit niche preemption, where the inferior competitor switched to a different form of nitrogen in the presence of the superior competitor; or dominant plasticity, where plasticity actually enhances competitive ability.  The authors looked at 4 species, 3 common and 1 rare(r), in an alpine tundra community, isolating naturally occurring pairs of each combination of species. These ‘competitive arenas’ were isolated, and other species within the arena were removed. After a year, the authors added N15 tracers to each arena, in three forms (NH4+, NO3-, and glycine): these tracers would allow them to track the N once it was incorporated into the plant tissue. The plants were then harvested and the amount of each type of nitrogen in each was measured. Plant biomass was also recorded, and used to estimate the ‘competitive response’ (basically the ratio of biomass when grown with a competitor compared biomass to when grown solo). Their findings were rather neat: the 3 common plants experienced no negative effect on biomass from growing in competition with the rare plant, but the rare plant had much lower biomass when grown in the presence of any of the common plants. Further, while the common plants showed changes in the form of N they used when growing with the rare plant, the rare plant did not switch its N preference. The rare plant’s lack of plasticity in response to competition may relate to its lower biomass when grown with superior competitors, and ultimately its lower abundance.

Although limited, these studies hint at the role that phenotypic plasticity could play in interspecific interactions. Unfortunately plasticity may be difficult to measure in many contexts, particularly since variation within a species can be attributed to genetic differences or phenotypic plasticity, and these factors must be teased apart. Further, there is an issue of differentiating the effects of resource limitations from ‘adaptive’ plastic changes in growth. While plants are relatively tractable for these types of studies (they’re sessile, they use limited abiotic resources), other organisms are less explored for a reason.

What these studies can’t address is the question of ‘how important is phenotypic plasticity, really’? Reviews of coexistence mechanisms list numerous possible ways by which coexistence is facilitated among species. For plants especially, the limited number of resources required for survival has lead to great consideration of the possible niche axes over which species can differentiate themselves. Phenotypic plasticity's contribution to coexistence may be that it provides another way by which plants can partition resources at very fine scales. And if nothing else, such results provide further evidence that variation within species may be an important component of coexistence.

Thanks to Kelly Carscadden for discussions on the topic.