Peace and conservation biology

A recent study published in Conservation Biology found that conservation hotspots are also hotspots for wars. Most of the wars (90%!) from 1950 to 2000 have been on countries that have these key areas for conservation, and 80% of these conflicts took place directly within the conservation hotspots. The authors mention many problems, such as the destruction of vegetation (i.e. the application of Agent Orange to detect enemies), poaching by soldiers, or that the cost of war could come at the expense of other government projects, such as conservation programs. But, there is not all bad news regarding biodiversity conservation (of course is Always bad news for humans), since these wars have created spaces with very low human impact (such as buffer areas with no human activity), or reduces economic activity that can make wartime a recovery period for some exploited species, and other unique situations. They conclude that since most of our biodiversity is in unstable regions, plans to conserve biodiversity should be also active in these regions, which are not the most appealing to work in, but may the most important. Also, that we need to integrate conservation biology into military and humanitarian programs that operate in these conflict zones.

These news are really sad, and I hope that we can live in peace for the benefits of all the species living in here (including, of course, Homo sapiens).

THOR HANSON, THOMAS M. BROOKS, GUSTAVO A. B. DA FONSECA, MICHAEL HOFFMANN, JOHN F. LAMOREUX, GARY MACHLIS, CRISTINA G. MITTERMEIER, RUSSELL A. MITTERMEIER, JOHN D. PILGRIM (2009). Warfare in Biodiversity Hotspots Conservation Biology DOI: 10.1111/j.1523-1739.2009.01166.x

The incredible spreadable weeds

Research into the spread of non-native species usually assumes a long time lag between introduction and rapid spread, and many studies cite 50 years as the lag time. The reason for believing this is that it is thought that there needs to be sufficient time for adaptations to fine tune the fit between the exotic and its new environment, or that densities are so low to start with, finding mates and buffering populations from stochasticity (i.e., Allee effects) takes time. However, Curtis Daehler at the University of Hawaii, collected information on purposeful plant introductions into Hawaii in the 1920s. 23 of those planted have become serious invaders and the herbacious species showed a lag time of 5 years and 14 years for woody species. Knowing that lag times can be much shorter then we previously thought means that monitoring and management activities need to much more aggressive. It seems we can no longer assume a period of relative safety after a new species in introduced, new records of non-natives needs to be followed active assessment and perhaps intervention.

Curtis C. Daehler (2009). Short Lag Times for Invasive Tropical Plants: Evidence from Experimental Plantings in Hawai'i PLoS ONE, 4 (2) DOI: 10.1371/Journal.pone.0004462

Increased access to science, but who gets to publish?

What role will open access (OA) journals play as science publishing increasingly moves to the internet and involves a more diverse array of participants? In a recent short article in Science, Evans and Reimer tried to answer this using citation rates from 8253 journals and examine trends in citation rate shifts. They found that researchers from wealthier countries were not likely to shift to citing OA journals while researchers from poorer countries did. The authors conclude that the overall shift to citing OA journals has been rather modest, but these journals have increased inclusion for researchers at institutions in poorer countries that cannot afford commercial subscriptions. However, there is an unfortunate flip side to the OA model -paying to publish. Most OA journals recoup the lack of subscription earnings by placing the financial onus on to the publishing scientists. This means that while researchers from poorer countries can now read and cite current articles in OA journals, they still are limited from publishing in them. True, most OA journals allow for deferring costs for researchers lacking funds, there is usually a cap to the frequency in which this can be done.

J. A. Evans, J. Reimer (2009). Open Access and Global Participation in Science Science, 323 (5917), 1025-1025 DOI: 10.1126/science.1154562

Functional traits and trade-offs explain phytoplankton community structure

After attending the presentation by Elena Litchman at the ASLO Aquatic Science Meeting in Nice three weeks ago I came across this paper. Although it was published already two years ago, this works need to be highlighted! Marine phytoplankton is important. It contributes approximately 50% to world primary productivity. Among other factors phytoplankton communities are structured by competition for limiting nutrients (mainly for nitrate and ammonia) in the ocean. Litchman et al. base their paper on the presumption that phytoplankton organisms can achieve higher competitive ability (Tilman’s R*) by different strategies. That is, the organisms can either increase their maximum nutrient uptake and/or growth rate or they decrease the minimum cell quota, the half saturation constant for nutrient uptake and/or their mortality. Litchman et al. tested if they can find constraints and trade-offs on the evolution of better competitive abilities (lower R*) in major phytoplankton groups. Specifically they asked if there is a positive relationship between maximum growth rate and R* which would show a gleaner-opportunist trade-off.
The authors show positive relationships between measurements for growth and nitrate uptake which can constrain the evolution on competitive ability. Indeed major groups of phytoplankton group along these trade-off curves. Whereas coccolithophores e.g. show low nitrate uptake rates and low half-saturation constants, diatoms and dinoflagelates show the opposite nitrate uptake strategy with high uptake rates and high half-saturation constants. A gleaner-opportunist trade-off, i.e. a positive correlation between maximum growth rates and R*which would result in a super species, could not be found across major groups but within the diatoms. The paper gives more results about trait differences among taxonomic groups and allometric scaling relationships. Trade-offs and different strategies in nutrient uptake are discussed in a very concise way either from a mechanistic physiological view as well as from the evolutionary history perspective.


Elena Litchman, Christopher A. Klausmeier, Oscar M. Schofield and Paul G. Falkowski (2009) The role of functional traits and trade-offs in structuring phytoplankton communities: scaling from cellular to ecosystem level. Ecology Letters. DOI: 10.1111/j.1461-0248.2007.01117.x

The next generation of invasive plants

The study of plant invasions has usually focused on plants adapted to colonizing areas immediately after a disturbance (early successional species or “weeds” by some definitions). An example of this, is the seminal work of Herbert Baker, with his list of traits to explain why some species become weeds and others do not (e.g. fast growth, production of lots of seeds, good dispersal.). So why do late-successional species (for example, forest understory species) not invade? The answer is: we did not look close enough - they indeed invade!! This is the point of a paper by Patrick Martin and collaborators, who study forests – which are usually known as “invasion resistant systems” – and the colonization of exotic shade-tolerant species in them. Their central point is that there have been larger numbers of introductions of early successional species compared to late successional species (or shade tolerant), and that forest dynamics are much slower than other systems (e.g. a forest gap must be created for a species that need disturbances to colonize). And it is for these reasons that we associate invasive plants solely with early successional species, and we see forests as invasion-resistant systems. We are now observing many highly invasive plants that are not disturbance dependent. These may be a lot harder to control and could have important detrimental effects on native communities.

Patrick H. Martin, Charles D. Canham, Peter L. Marks (2009). Why forests appear resistant to exotic plant invasions: intentional introductions, stand dynamics, and the role of shade tolerance Frontiers in Ecology and the Environment DOI: 10.1890/070096

40% believe in evolution, but only 25% do not!

Gallup released a poll, that coincides with Darwin's birthday, which examines American's belief in biological evolution. It is a great poll, breaking down belief patterns across education attainment, age , religiousness, etc.

However, several reports and blogs about this poll disparage Americans for their lack of scientific sophistication, but I think that the results are far more positive then I would have guessed. Only 25% outright deny evolution! I would have thought a clear majority would take this stance as was shown in 2005. A further 36% do not have an opinion, and as scientists and educators, these folks are the reason why we educate and hold events like Darwin Day. Thank you to all those who work so tirelessly promoting science education and literacy, like those at NCSE.

Charles Darwin, founder of evolution AND ecology

Perhaps a good alternative title should be: “Why we need a second modern synthesis”

Darwin is rightfully seen (or vilified in some quarters) as the founder of modern evolutionary biology. He gave the naturalists of that era an observable and testable mechanism explaining species change and for understanding the similarities and differences among species. As we celebrate Darwin’s 200th birthday and the 150th anniversary of the publication of the Origin of the Species, it seemed right to think about Darwin’s contributions beyond just evolutionary change, namely ecological patterns and processes.

I’ve read Origin probably half a dozen times now and as an ecologist, I am always amazed by the depth and breadth of Darwin’s insights. Every time I read it, there are passages that directly relate to what I happen to be thinking about or working on at the time, which leads me to the conclusion that he thought a lot about what scientists would come to call ecology. Though the word “ecology” wouldn’t be invented for another seven years (by Ernst Haeckel in 1866) and the first ecology text book didn’t appear until 1895 (by Eugenius Warming, and which includes interesting Lamarckian invocations in the last chapter), Darwin thought and wrote about ecology extensively.

In the Origin (1st edition), Darwin makes predictions about ecological patterns. On page 109, he states, “a … larger number of the very common and much diffused or dominant species will be found on the side of larger genera”. That is community dominance likely relays on inherited traits linked to species success. This certainly sounds like the result of some recent, interesting papers (e.g., Strauss et al.*).

Almost the whole discussion in the Struggle for Existence chapter is about ecological interactions and the severity of negative interactions, which stems from the fact that populations, if unchecked, will increase exponentially (i.e., page 116). We all know from work by ecologists such as Connell and Huston that those negative, deterministic interactions can be overridden by non-equilibrium processes, especially disturbances. Here again Darwin’s observations lead him to this conclusion; “If turf which has long been mown …be let to grow, the more vigorous plants gradually kill the less vigorous” and he observes that diversity in a plot goes from 20 species to 11 when the disturbance is removed.

Further, we often think of Darwin’s view of the environment as a selective pressure (e.g., fur thickness), but he also saw the environment as a determinant of species interactions. Lush places support a lot of species and the control of populations is due to competitive interactions, whereas in harsh places, populations are controlled by “injurious action” of the environment (e.g., page 121). Thus there is a shift from biotic to abiotic controls on ecological processes.

I think that we have collectively forgotten that evolution directly informs our expectations and predictions of ecological patterns and processes. While ecological geneticists drove much of the modern synthesis in the mid 1900’s by incorporating ecology (namely selection) into evolutionary processes, the reverse, bringing evolution into ecology is only now really starting to happen. Lets hope this second modern synthesis completes Darwin’s vision.

Stability begets diversity

A classic hypothesis to explain the high diversity found in tropical rain forests is that areas within the tropics served as climatic refuges during Pleistocene global climate fluctuations (e.g., ice ages). These refuges beget diversity because they face much lower extinction rates then non-refuges and they are older, allowing speciation events to accrue. This hypothesis has proven controversial as evidence has been circumstantial and circular (i.e., high diversity areas are taken as evidence of a refuge and the outcome of a refuge is high diversity.).

This conundrum has been solved by Ana Carnaval, a postdoctoral researcher in Craig Moritz's lab at UC Berkeley, and colleagues. They use patterns of diversity to identify probable refuges and then support several independent hypotheses about refuge effects on patterns of frog diversity. They show 1) that there is higher genetic diversity within and among refuge populations relative to non-refuges. 2) They show a multi-species pattern of recent population expansion in non-refuges from adjacent refuges. 3) The absence of isolating divergence in non-refuges because of a lack of time. Finally, 4) strong phylogenetic patterns of between refuge structure, indicating periods of isolation and divergence.

This paper reveals that hypotheses about the origin of species diversity in hotspots can be tested by using genetic divergence below the species level. Not only does this strongly support the spatial refuge hypothesis for tropical diversity patterns but it also elegantly intertwines microevolutionary processes with macroevolutionary patterns. There couldn't have been a more appropriate study published in the week before Darwin's birthday.

A. C. Carnaval, M. J. Hickerson, C. F. B. Haddad, M. T. Rodrigues, C. Moritz (2009). Stability Predicts Genetic Diversity in the Brazilian Atlantic Forest Hotspot Science, 323 (5915), 785-789 DOI: 10.1126/science.1166955

Shortening the R curve

I am a strong proponent of R for all data management, analysis and visualization. It is a truly egalitarian analysis package -open source and community-contributed analysis packages. The true power comes from complete control and automization of your analyzes as well as publicly accessible new functions created by members of the community. However, the drawback for a lot of people has been the rather steep learning curve, as with any programing language. But there are now a plethora of good books available that help shorten this curve. The Human Landscapes blog as reviewed and ranked introductory and reference R books, which should serve as an invaluable resource for those striving to become aRgonauts.

Don’t miss the mechanism when testing for biodiversity effects

Variation in the strength of diversity effects among experimental studies raise the question when and where consequences of diversity loss is strongest. As in grassland experiments, diversity effects on plant biomass production can be observed in systems with marine macroalgae. However, even among marine macroalgae experiments variation in the strength of the diversity effect cannot be explained because of largely differing experimental set-ups (i.e. long-termed vs. short-termed studies, mesocosms vs. field experiments, using inter- or subtidal habitats). From literature Stachowicz et al. assumed that short termed factors regulating diversity effects in such systems could be attributed to spatial complementarity in photosynthesis rates or different limiting nutrients. Long-term regulating factors could be attributed to habitat differentiation, temporal complementarity, fascilitation, recruitment and natural heterogeneity of substrate. In a very elegant way Stachowicz and his co-workers tested whether mechanisms responsible for diversity effects change with experimental procedure and/or study type within the same marine algae system. In a series of three experiments, that is a short-termed mesocosm with transplanted thalli, a short-termed (two month) field-experiment with naturally recruited thalli and heterogeneous substrate, and in a long-term (three years) field-experiment, the authors were able to show that strong diversity effects are positively correlated with experimental duration, environmental heterogeneity and population responses (recruitment). Whereas in the mesocosm species identity affected biomass production, in the field studies it was species richness but not identity. Fractional change of species biomass could be explained by species identity in the mesocosm, and by both identity and richness in the field. The authors are making an important point by showing that mechanisms for diversity effects are not exclusive but occur together and become stronger over time. They conclude that the absence or the detection of only weak diversity effects in short-termed experiments does not necessarily mean that there is no effect because such approaches detect only a limited number of potential mechanisms.


John J. Stachowicz, Rebecca J. Best, Matthew E. S. Bracken, Michael H. Graham (2008). Complementarity in marine biodiversity manipulations: Reconciling divergent evidence from field and mesocosm experiments. Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.0806425105

Local extinctions reveal metacommunity dynamics.

Metacommunity dynamics (i.e., that dispersal limitation among locales creates spatially-contingent community processes) have been in vogue over the past half-decade. Many of the advances in this field have come from theoretical models, computer simulations, artificial laboratory assemblages of micro-organisms (with yours truly being a major offender) and field experiments using small-bodied, short-lived organisms. An oft-repeated criticism has been that the necessary conditions for metacommunity processes are what are manipulated in simulations or lab tests and that simple extinction-colonization dynamics are rarely observed for larger, longer-lived organisms. In a recent paper by Kevin Burns and Christopher Neufeld, high levels of extinction and colonization are shown in patchy communities of woody plants. They sampled 18 islands off the west coast of Canada in 1997 then again in 2007 and found that substantial numbers of local extinctions were observed. These results reveal that what we often think of as relatively stable communities (woody plant species) are actually quite dynamic, creating the conditions were metacommunity processes are an important mechanisms driving patterns of diversity. They further show that communities with greater exposure to ocean storms had higher extinction risk and species with hardier leaves were less prone to local extinctions.

Kevin C. Burns, Christopher J. Neufeld (2009). Plant extinction dynamics in an insular metacommunity Oikos, 118 (2), 191-198 DOI: 10.1111/j.1600-0706.2008.16816.x

I have one of the worst jobs in science!

According to Popular Science's annual ranking of the worst jobs in science, I (no really me!) have one of the worst jobs. They list scientists doing triage -that is having to evaluate which species to save given that we can't save all, as being particularly crummy. They specifically cite my study of phylogenetic uniqueness and ecosystem function as an example. Well I guess it is a little depressing to try to evaluate which species should be saved over others, but I don't think it is as bad as a medical waste burner...

Small experimental plots predict entire ecosystem responses! (if you work in peatlands…)

The possibility of extrapolating results from experimental plots to larger (or “real”) scales is a major issue in ecology. For several reasons ecologists conduct manipulative experiments in relatively small experimental units. This that has been suggested to be a big problem since the effect of the studied factor could change with spatial scale. An example of this can be found in biological invasions where there is some evidence that the more species you have at a small scale (e.g. a plot), the less likely an exotic can invade; but, at the regional level, the more species there are, the more likely that exotics can invade, so invasion has a scale-dependent response to species richness. However, if you work on peatlands you are very lucky! A recent paper by Magdalena Wiedermann and collaborators found that in peatlands, experiments in 2 x 2 meter plots represented really well what was happening at the entire ecosystem level. They compared a manipulative experiment where they added nitrogen at different concentrations, with an observational study in a region with gradient of nitrogen concentrations similar to the ones used in the experiment. They found that cover of Sphagnum and vascular plants could be explained by the levels of nitrogen equally well at plot and regional scales

Magdalena M. Wiedermann, Urban Gunnarsson, Mats B. Nilsson, Annika Nordin, Lars Ericson (2009). Can small-scale experiments predict ecosystem responses? An example from peatlands Oikos DOI: 10.1111/j.1600-0706.2008.17129.x

Best job site, ever

For those ecologists and evolutionary biologists actively on the academic job market, there are a number of sources to get job ads (such as Science careers). But growing in popularity and by far the best job resource is the ecology job wiki. This site is a user modified site (as wikis are) where people list current job postings. But more than this people can actively discuss specific jobs, frustrations, updates, strategies, etc. For example, once a position starts interviewing, often an update will appear on the wiki informing all that interviewees have been selected Thus alleviating the feeling of limbo that we have when information is scarce. While it may not be entirely comprehensive in that not every single advertised job will appear, it does offer more information and the opportunity to share with others.

Good luck job hunters! Hopefully the job wiki is useful.

Researcher spotlight: Tadashi Fukami

Increasingly, ecological explanations for extant community patterns are relying on dynamics operating across multiple spatial and temporal scales, linking small and large scales, and the here and now with evolutionary history. The traditional boundaries of sub-disciplines are blurring. I think that few other young scientists straddle these boundaries as successfully as Tad Fukami, and new assistant professor in the Department of Biology at Stanford University. Tad uses a broad array of theoretical and experimental approaches to understand how ecological communities are put together. From laboratory microcosms to rat-infested islands, and from the computer to remote locations, he is able to pull together disparate pieces of information into a central narrative about the assembly of communities.

I asked him why the question of community assembly interested him so much, and he gives much credit to his advisors, Jim Drake (also my PhD advisor) and Dan Simberloff both in the Department of Ecology and Evolutionary Biology at the University of Tennessee. But more than this, he says that:

“you need to look into the historical background of species interactions to understand the apparently inexplicable variation in the way species interact and the way communities are structured by the interactions.”

and certain aspects of this research obviously excite him. He goes on to say:

“One particularly intriguing thing is the great effect that small chance events that cause variation in early immigration history can have on long-term community development.”

Most ecologists gain their expertise by coming to understand and appreciate the details and intricacy of particular organisms or ecosystems. But Tad is especially noted for his use of an amazingly broad assemblage of systems and methods. I asked him why he used so many different systems, and how he chose those to test his ideas. He said that his work has benefitted from many exciting collaborations and that he has:

“been very lucky to meet many great people who have expertise on specific organisms and systems that a person with diffuse interests like me doesn't have.”

But I think that there may be something deeper and more reassuring. That is, the fact that one could study a multitude of systems, testing the basic dynamics of community assembly, means that there are regularities in how communities are assembled. That you can study stochastic historical events in bacterial microcosms and inform your understanding of plant succession means that while we individually take on these, at times, daunting research projects, our collective understanding of ecological processes are threaded together in a great fabric. And no one is a microcosm of this more than Tad Fukami.

Key recent papers

Fukami, T., Beaumont, H. J. E., Zhang, X.-X. & Rainey, P. B. (2007) Immigration history controls diversification in experimental adaptive radiation. Nature 446: 436-439.

Fukami, T., Wardle, D. A., Bellingham, P. J., Mulder, C. P. H., Towns, D. R., Yeates, G. W., Bonner, K. I., Durrett, M. S., Grant-Hoffman, M. N. & Williamson, W. M. (2006) Above- and below-ground impacts of introduced predators in seabird-dominated island ecosystems. Ecology Letters 9: 1299-1307.

Fukami, T., Bezemer, T. M., Mortimer, S. R. & Van der Putten, W. H. (2005) Species divergence and trait convergence in experimental plant community assembly. Ecology Letters 8: 1283-1290.

Mutualistic networks for beginners

Research on the role of positive interactions in ecology has been increasing rapidly in the last 15 years or so. An example of this is the study of mutualistic networks, which are among the most exciting and fast-moving areas of ecology. In the last few years a number of really amazing papers have shown that studying these networks can really increase our understanding of natural systems. In a recent review papers in Frontiers in Ecology and the Environment Jordi Bascompte describes briefly but thoroughly the history and current state of this field of research. Starting with observations by Charles Darwin, he describes the importance of positive interaction and how during many decades research had been focused on single plants or pollinator, or highly coevolved interactions which has produced fundamental information. However, now with this network approach a lot can be learn about their stability and effects of species extinctions, among many other aspects. A very interesting comparison that is made is with the Internet. Apparently, a lot has been learn from this human made network, where studies have shown that networks are more stable and resistant to random attacks if they are heterogeneous (some part of the network being much more connected than most) that if they are homogeneous (all nodes being equally important / connected). The internet is actually a heterogeneous network, and so are the mutualistic networks. Bascompte also mentions the role of non-reductionist approach to science in the study of this highly complex networks since studying the parts of the network doesn’t allow researches to fully understand its behavior (e.g. you can know a lot about pairs of interactive species, but it has been proven that it will not tell you about the stability of the network to say, the extinction of same of its members). Also, he highlights the role of multidisciplinary approaches to complex problems, since the study of mutualistic networks has relayed heavily on research from other areas of science.

Jordi Bascompte (2009). Mutualistic networks Frontiers in Ecology and the Environment DOI: 10.1890/080026

However you skin them, cats have important ecosystem consequences

For disclosure’s sake, I was the editor who handled this paper, and much of this post comes from an editorial I wrote for this paper.

Islands experience the greatest impacts from the invasion of non-indigenous species and are also at the forefront of efforts to eradicate problematic species and mitigate negative impacts. Bergstrom et al. elegantly studied the habitat and ecosystem consequences from the eradication of feral cats from Macquarie Island, a subantarctic island and a world heritage site administered by the state of Tasmania, Australia. This island has undergone a series of invasions and both cats and rabbits were introduced in the 19th century. Cat predation resulted in drastic declines in seabird populations, likely causing two extinctions, and thus a cat eradication programme began in 1985 with the last cat killed in 2000. The authors recognized that the feral cats had become fully ingrained in the island food web, and they show that despite the introduction of the Myxoma virus prior to the cat eradication, rabbit populations exploded after the cat removal. These large rabbit populations caused pervasive vegetation changes. The authors sampled plots before and after the eradication and found that vegetation in these plots shifted from large, long-lived plants to smaller, faster growing species, some of which are themselves non-indigenous to the island. Further, satellite imagery revealed that more than one-third of island has since undergone vegetation change, likely resulting in large-scale habitat alterations.

What these results show us is that the consequences of species eradication may be complex with unintended results. Non-indigenous predators and meso-predators can become important components of island food webs –so important that their subsequent removal can have repercussions felt throughout the entire food web. While trying to protect seabird populations is undoubtedly worthy of management action (including eradication programmes), adequately predicting ecosystem-level consequences should be the basis directing such activities. Planning for such management activities must include information gained through experimentation, modeling and natural history. By using all available tools and knowledge, management activities can have a better chance of succeeding and harmful unintended consequences minimized.

Dana M. Bergstrom, Arko Lucieer, Kate Kiefer, Jane Wasley, Lee Belbin, Tore K. Pedersen, Steven L. Chown (2009). Indirect effects of invasive species removal devastate World Heritage Island Journal of Applied Ecology, 46 (1), 73-81 DOI: 10.1111/j.1365-2664.2008.01601.x

Who is Naïve, the invaders or the natives?

Why some species can invade natural ecosystems and many others cannot, is a question that doesn’t have an answer. Many ideas have been proposed to explain this, with relative success, but very low predictability. Most of the ideas have been focused on the factors that promote invasion (i.e. why successful invaders are successful). In a recent ideas paper Koen Verhoeven and collaborators propose a different approach. They ask the question, how ecological mismatches between natives and exotics can explain invasion? They propose a series of predictions based on plant defenses and plant enemies (herbivores, pathogens). They propose that the mismatches between exotic plants and their new enemies could explain their success or failure. For example, if a plant presents a new type of toxic chemical compound that the local herbivores have never encounter and cannot deal with, it would be a clear advantage for the plant (this is related to the novel weapons idea). On the other hand, if the plant has defenses that need to be trigger by a particular enemy (for example an induced defense triggered by a specific chewing insect) that could be a disadvantage for it. They propose that biotic resistance (when the native community resist the invasion) and enemy release (when an exotic invades due to experiencing less pressure by enemies than in its native range) are not oppose ideas but could be the different outcome of these mismatches.

This paper propose a very interesting approach to study some cases of successful and failed invasions, and I look forward for empirical tests of this idea.

Koen J. F. Verhoeven, Arjen Biere, Jeffrey A. Harvey, Wim H. van der Putten (2009). Plant invaders and their novel natural enemies: who is naïve? Ecology Letters, 12 (2), 107-117 DOI: 10.1111/j.1461-0248.2008.01248.x

Grazers chew, cereal gets sick

Managing plant disease is a major part modern agricultural practice, so it is important to understand the basic ecological dynamics of plant diseases. Some theoretical studies have found that the prevalence of plant diseases can be affected by the amount of herbivory in a system. Given that human land-use and the removal of top predators from many ecosystems has fundamentally changed the abundance and distribution of many herbivores, the repercussions of herbivory can have important cascading consequences throughout foodwebs –including disease dynamics. In the first experimental study of the interaction between herbivory and plant disease, the forthcoming paper in PNAS by Elizabeth Borer and colleagues, shows that increased exposure to large herbivores (e.g., mule deer) resulted in higher disease prevalence in the plant community. The disease they studied, barley and cereal yellow dwarf virus (shown in the photo), is transmitted by aphids, so herbivory does not cause increased transfer. Rather, herbivores changed community composition resulting in higher abundances of very susceptible species, creating a feedback where higher abundances resulted in higher infection rates due to a larger pool of potential hosts near by. These results are important for two reasons. First, this particular virus is an important agricultural disease. Secondly, we need to take a whole-community approach to understanding disease dynamics because these dynamics are not only a property of host-vector-pathogen interactions, but are subject to direct and indirect effects from interactions with other community members.

E. T. Borer, C. E. Mitchell, A. G. Power, E. W. Seabloom (2009). Consumers indirectly increase infection risk in grassland food webs Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.0808778106

Fisheries and food webs: a whole system approach to cod recovery

The collapse of cod fisheries around the world is a breathtaking example of over exploitation and poor planning. But with reduced fishing pressure why have cod populations shown such slow or stagnant population recovery? This has been an extremely active area of research for fisheries scientists. In a recent paper by Casini and colleagues in the Proceedings of the National Academy of Sciences, they found that over-fishing of cod in the Baltic Sea has led to a regime shift, where a small planktivorous fish called sprat now dominate the system. But its not just that there is a new dominant, sprat seem to really change how the ecosystem operates, to the detriment of cod recovery. When the ecosystem was cod dominated, zooplankton abundance was unrelated to sprat abundance but did appear to be dependent on hydrological environmental variables. In the new sprat-dominated system zooplankton numbers are negatively related to sprat abundance and the environmental controls of zooplankton abundance do not appear to be important. So why is this bad for cod recovery? Adult sprat compete with larval and juvenile cod for zooplankton and sprat consume cod eggs. The authors suggest that a good cod recovery plan will involve managing key aspects of the food web. This paper reveals how a whole food web or ecosystem approach is necessary for understanding population controls of important fisheries species.

M. Casini, J. Hjelm, J.-C. Molinero, J. Lovgren, M. Cardinale, V. Bartolino, A. Belgrano, G. Kornilovs (2009). Trophic cascades promote threshold-like shifts in pelagic marine ecosystems Proceedings of the National Academy of Sciences, 106 (1), 197-202 DOI: 10.1073/pnas.0806649105

Review or publish; the curse of the commons

Need we be concerned about the volume and quality of manuscript reviews for journal submissions? In a recent editorial published in Ecology Letters by Michael Hochberg and colleagues, they answer yes, we should be concerned. They argue that manuscript reviewing is suffering from a tragedy of the commons, where growing submission rates to top journals is overburdening potential reviewers. This overburdening has two causes. First, that researchers tend to send their manuscripts to journals based on impact factors, regardless of the appropriateness of the manuscript for the receiving journal. Second is that authors view negative reviews as stochastic happenstance and in the rush to resubmit do little to improve their manuscript.

While the concerns are real, and the authors do suggest common sense approaches to publishing (i.e., choose appropriate journals and get colleagues to review drafts -something most of my colleagues do), there is little discussion of what incentives could be offered. The curse of the commons is when individual motives do not benefit the greater good, thus incentives could be used to alter motives potentially benefiting the larger community.

A number of journals now offer free access or free color figures in future publications for reviewing or even offering payment. Perhaps the move towards reduced length rapid turn around publications is part of the problem and that we should be valuing longer, more detailed papers (the classic quantity vs. quality problem). Whatever the potential solutions, it is promising to see journals, especially top-ranked ones like Ecology Letters, discussing these issues.

Michael E. Hochberg, Jonathan M. Chase, Nicholas J. Gotelli, Alan Hastings, Shahid Naeem (2009). The tragedy of the reviewer commons* Ecology Letters, 12 (1), 2-4 DOI: 10.1111/j.1461-0248.2008.01276.x

How to plan an experiment that could last 99 years

For a number of reasons, including the fact that most grants only allow for research over a time span of 1-3 years, ecologists and evolutionary biologists usually plan experiments that last few years (with notable exceptions, such as the LTER). A usual approach to study long term phenomena is to take advantage of “natural” experiments. This allows us to understand about processes over long time periods, but usually with limited control on the initial conditions.

In a recent paper by Thomas Bruns and collaborators I learned about another way. They study spores viability of an important genus of ectomycorrhizal fungi, symbiont of Pinaceae: Rhizopogon. Pinaceae (the family of pines and other conifers) need ectomycorrhizal fungi to survive and usually spores and seeds are dispersed independently. It was not known how long their spores can last, which has very important implications, for example for colonization of areas not previously colonized by Pinaceae, or colonization after large scale disturbances, since if seeds cannot find mycorrhizae they have really few chances of survival. Now we know, based on this research that spore banks can be build and last probably decades.

What they did is really interesting, and was inspired on a previous study on seeds. They planted known number of spores of several species of Rhizopogon in terracotta pots, that were later planted into the ground (to mimic natural conditions). They planted 16 replicates, and they plan to open and analyze them later in the century based on the spore viability (for example, if in a few years most spores seem to be not viable that may reduce the expected length of the experiment to increase resolution). This paper found that after 4 years the inoculum potential of these spores seems to be increasing with time. I found the approach used in this experiment really fascinating and I look forward to see what happens in the next years!

Thomas D. Bruns, Kabir G. Peay, Primrose J. Boynton, Lisa C. Grubisha, Nicole A. Hynson, Nhu H. Nguyen, Nicholas P. Rosenstock (2009). Inoculum potential of
spores increases with time over the first 4 yr of a 99-yr spore burial experiment
New Phytologist, 181 (2), 463-470 DOI: 10.1111/j.1469-8137.2008.02652.x

Podcasts

Keeping up with scientific literature is a challenge. Even though is it possible to do a descent job in your super specific area of expertise, it is almost impossible to keep up with literature in general areas of science, such as ecology or evolution, given the hundreds of papers that are published each week. There are many tools that can be used to stay (kind of) updated. One of those are podcasts. If you are reading this blog (and if you frequently read blogs) it is likely that you know a lot about podcasts, but I found remarkable the few people that profits from this awesome resource in academia. There are many nice podcast on science, but few on ecology. The new podcast of Frontiers in Ecology and the Environment is an awesome one, and I hope that other journals start doing the same thing (let me know if they are more!). This ESA podcast, with music by Nick Gotelli (excellent choice by the way, click here for more of his music), is surely one that you want to have in your mp3 player when you go for walk.

Other nice ones (but not specific on ecology or evolution) are the Nature podcast and the Science podcast, and my preferred one, the Scientific American podcast.

Ecology's romantic period

As an ecologist of the 21st century, I often think about the early ecologists from the period between 1900 and 1920 (Clements, Forbes, Warming, Spalding, Grinnell, etc.) and wonder what it was like for them to do their science. Being a scientist today usually means being a technophile. Amazing advances are made through technology, from new and larger genomes to running mind-bogglingly complex computer simulations with a scale and scope that would have been simply incomprehensible a generation ago. We also have a vast foundation of ideas, theories, hypotheses and observations that drive our current quest for knowledge.

Ecologists of 1900 did not have access to our level of technology, they did not have this huge foundation of knowledge informing their science. In fact the totality of human knowledge of the ecological world, from Aristotle to Darwin to Haeckel to Warming, could fit on a single bookcase. And for this I envy them. Every observation was something new and exciting. Hypotheses created to explain observations were novel and creative. I may be romantic, but the idea of a wide open frontier of ideas seems so exciting to me.

Being an ecologist today means competing in a crowded market of ideas. Much of our creative work involves revising and fine-tuning existing hypotheses or finding new technological and computation methods to better test existing hypotheses. Sometimes it feels like the scientist who yells the loudest in this crowded market will be heard. And so I wonder, would it be worth giving up the technological advances to simply stick your head in a hole and describe a brave new world.

P.S. I love both the photos of Frederic Clements shown here. The first is of him near Santa Barbara, CA were he would spend his winter months researching plant communities. The second is of him (head in hole) and his wife Edith, also an ecologist, apparently studying below ground interactions among plants.

Why this blog?

I decided to start The EEB and flow because I think this blog is needed. While there are some great science blogs dedicated to evolution (Dechronization and Evolutionary Novelties, for example) there is conspicuously little blogging of recent advances in ecology and evolutionary ecology. My short term plan is to highlight recent important papers, discuss ecology and conservation news and post thoughts on life in academic ecology and evolution. My long term goal will be to host a community generated blog where new papers and findings are discussed. Given that the only real community generated discussion of recent papers is a paid subscription (Faculty of 1000) the time may be right for a community blog. But stay tuned.

Whence diversity?

It is a truism to say that ecological communities are diverse. They often contain dozens or hundreds or thousands of species that represent many of the deep origins in the tree of life. A recent paper by Prinzing and colleagues published in Ecology Letters tested the hypothesis that communities of plants that include more of the ancient divergences from the evolutionary tree of plants should also contain a greater diversity of physical traits. They examined over 9000 plant communities and found that those that contain fewer evolutionary lineages actually had greater trait diversity than those randomly assembled from more lineages. This result reveals that when communities are assembled from a few lineages (likely due to strong environmental selection -e.g., drought tolerance) those members tended to have evolved large differences. That is, while species may be constrained to certain habitat types due to their evolutionary heritage, successful coexistence depends on maximizing differences.
Andreas Prinzing, Reineke Reiffers, Wim G. Braakhekke, Stephan M. Hennekens, Oliver Tackenberg, Wim A. Ozinga, Joop H. J. Schamine, Jan M. van Groenendael (2008). Less lineages more trait variation: phylogenetically clustered plant communities are functionally more diverse Ecology Letters, 11 (8), 809-819 DOI: 10.1111/j.1461-0248.2008.01189.x