How can evolution inform conservation decisions?

First of all, let me apologize for the lack of blog posts over the past 2 weeks, I've been busy visiting the Olympics and reading a couple of hundred blogs, judging them for the Research Blogging awards.

The conservation of biological diversity is a major imperative for biologists. International agreements such as the Convention on Biological Diversity and intergovernmental exercises, such as the Millennium Ecosystem Assessment, call upon scientists to provide evidence on the current state of biological diversity and to evaluate solutions for reducing diversity and ecosystem function loss. Critical to these efforts have been the work of ecologists, conservation biologists and ecological economists. However, seemingly missing from the conversation about the state of biodiversity knowledge has been evolutionary biologists. Are they primarily concerned with describing historical processes and mechanisms of biological change, or do they have substantive knowledge and ideas that should be viewed as a critical component of any scheme to conserve biological diversity?

In a recent paper in Evolution, Hendry and a number of coauthors convincingly make the case that evolutionary biology is a necessary component for conservation. Evolution offer four key insights that should inform conservation and policy decisions. First, they point out that evolutionary biologists are in the business of discovering and documenting biodiversity. They are the primary drivers behind long-term, sustained biological collections, because they need to know what exists in order to better understand evolutionary history. With millions of species awaiting scientific discovery, their efforts are critical to measuring biodiversity. But not only are they discovering new species and enumerating them, they are uncovering their evolutionary relationships, which gives conservationists better information about which species to prioritize. What Vane-Wright famously called 'the agony of choice', with limited resources, we need to prioritize some species over others, and their evolutionary uniqueness ought to be a factor. More than this, evolutionary biologists have developed pragmatic tools for inventorying and sharing data on biodiversity at all levels, from genes to species, which is available for prioritization.

The second key insight is that by understanding the causes of diversification, we can better understand and predict diversity responses to environmental and climatic change. By understanding how key functional traits evolve, we can develop predictions about which species or groups of species can tolerate certain perturbations. Further, research into how and why certain evolutionary groups faced extinction can help us respond to the current extinction crisis. For example, the evolutionary correspondence between coevolved mutualists, such as plants and pollinators, can be used to assess the potential for cascading extinctions. These types of analyses can help identify those groups of related species, or those possessing some trait, which make species more susceptible to extinction.

Thirdly, evolution allows for an understanding of the potential responses to human disturbance. Evolutionary change is a critical part of ecological dynamics, and as environment change can result in reduced fitness, smaller population sizes and extinction, evolution offers an adaptive response to these negative impacts. Knowing when and how populations can evolve is crucial. Evolutionary change is a product of genetic variation, immigration, population size and stochasticity, and if the ability to evolve to environmental change is key for persistence, then these evolutionary processes are also key.

Finally, evolutionary patterns and processes have important implications for ecosystem services and economic and human well-being. Both genetic and evolutionary diversity of plant communities has been shown to affect arthropod diversity, primary productivity (including work by me) and nutrient dynamics. Thus understanding how changes in diversity affect ecosystem processes should consider evolutionary processes. Further, exotic species are often cited as one of the major threats to biodiversity, and evolutionary change in exotics has been shown to increase exotic impacts on native species.

All together, these key reasons why evolution matters for conservation, mean that developing sound management plans requires considering evolution patterns and processes. We can use evolution to our benefit only if we understand how evolution shapes current dynamics. The challenge to evolutionary biologists is the same as it was for ecologists perhaps 15 to 20 years ago, to present their understanding and conservation ideas to a broader audience and to engage policy makers. To this end, the authors highlight some recent advances in incorporating evolutionary views into existing biodiversity and conservation programmes –most notably into DIVERSITAS.

Just like ecological processes and dynamics cannot be fully understood without appreciating evolution ancestry or dynamics, developing an extensive, expansive conservation strategies must take into account evolution. I hope that this paper signals a new era of a synthesis between ecology and evolution, which produces precise, viable conservation strategies.

Hendry, A., Lohmann, L., Conti, E., Cracraft, J., Crandall, K., Faith, D., Häuser, C., Joly, C., Kogure, K., Larigauderie, A., Magallón, S., Moritz, C., Tillier, S., Zardoya, R., Prieur-Richard, A., Walther, B., Yahara, T., & Donoghue, M. (2010). EVOLUTIONARY BIOLOGY IN BIODIVERSITY SCIENCE, CONSERVATION, AND POLICY: A CALL TO ACTION Evolution DOI: 10.1111/j.1558-5646.2010.00947.x

Research blogging awards; and thanks

Hi all, nominations for Research Blogging's annual awards will close Feb. 11, so be sure to nominate any research blogs you think deserve consideration. The top prize is $1000, and there are several smaller, field-specific awards as well. A panel of judges (with me being a member) will create a short list of blogs for each category and registered users on Research Blogging will be able to vote for the winners.

And a thank you to whoever nominated the EEB and Flow.

Predator-human conflict: the emergence of a primordial fear?

There is something terrifying and at the same time captivating about the idea of a large, wild, mysterious predator. The very idea that a large predator is near by makes us feel vulnerable. Every year, news stories about wild animal attacks appear in numerous publications and on many television shows. Human death at the fangs or claws of a wild beast is at the heart of many legendary stories and probably sown into the fabric of our being by millennia of ever present risk from large predators. This characteristic of our human experience, I think, dictates our response to animal attacks. Stories of animal attacks are usually concluded with statements about having or attempting to track down and destroy the guilty animal.

Such is the case for three recent animal attacks in Canada. In late October, 2009 in Nova Scotia, a raising 19-year old folk singer was killed by a couple of coyotes while hiking. It is difficult to find meaning in such a horrendous death, but the narrative, told by reporters, was essentially to rest assured that one of the coyotes had been killed and the other was being tracked and would be destroyed. There were two cougar attacks in early January, 2010 in British Columbia, that basically ended with the same reassurance. In the first, a boy was attacked and his pet golden retriever courageously saved his life. A police officer arrived a shot the cougar which was mauling the dog -an obviously legitimate response, and the news story again reassures us that the animal was destroyed. And don't worry the hero dog survived. In the second cougar attack, another boy was attacked, and this time his mother saved his life. But again the story narrative ended by reassuring us that the guilty cougar, and another cat for good measure, were destroyed the next day.

After reading these stories, I asked myself two things. Why is our response to destroy predators that attack? And why do we need to be reassured that this has happened? In defence of the predators, they are just doing what their instincts tell them to do, and most often their only mistake is that they selected their prey poorly. But the reality is that there are only 2-4 cougar attacks per year and only 18 fatalities over the past 100 years. Why do we fear such a low probability event? In contrast, automobile accidents are the leading cause of death in children under 12 in North America. Thousands of people die, and millions injured in car accidents every year in North America. Recently, in Toronto, were I live, 10 pedestrians were killed in 10 days, yet my heart doesn't race when I cross a street. If our fears and responses to human injury and death reflected the actual major risks, we would invoke restrictive rules regarding automobile use.

We believe that we can live with nature in our backyard. But when that close contact results in an animal attack, human fear seems to dictate an irrational response. Do we really expect predators to obey our rules? Can we punish them enough to effectively tame them? We cannot, and I hope that our approaches to dealing with human-animal conflict can better deal with animal attacks, in a way that does not subjugate large predators to whims of our fears.

The evolution of a symbiont

The evolution of negative interactions seems like a logical consequence of natural selection. Organisms compete for resources or view one another as a resource, thus finding ways to more efficiently find and consume prey. However, to me, the natural selection of symbiotic or mutualistic interactions has never seemed as straight forward (expect maybe the case where one species provides protection for the other, such as in ant-plant mutualisms). A specific example is the rise of nitrogen-fixing plants, who supply nutrients to bacteria called rhizobia capable of converting atmospheric nitrogen into forms, such as ammonia, usable to the plant host. Not only has this symbiosis evolved, but has seemed to evolve in very evolutionarily distinct lineages. The question is, what are the mechanisms allowing for this?

In a recent paper, Marchetti and colleagues answer part of the question. They experimentally manipulate a pathogenic bacteria and observe it turning into a symbiont. They transferred a plasmid from the symbiotic nitrogen fixing Cupriavidus taiwanensis into Ralstonia solanacearum and infected Mimosa roots with it. Plasmid transfer among distinct bacteria species is common and referred to horizontal genetic transfer (as opposed to vertical, which is the transfer to daughter cells). The presence of the plasmid caused R. solanacearum to quickly evolve into a root-nodulating symbiont. Two regulatory genes lost function, and this caused R. solanacearum to form nodules and to impregnate Mimosa root cells.

This extremely novel experiment reveals how horizontal gene transfer can supply the impetus for rapid evolution from being a pathogen to a symbiont. More importantly it reveals that sometimes just a few steps are required for this transition and how distantly-related bacterial species can acquire symbiotic behaviors.

Marchetti, M., Capela, D., Glew, M., Cruveiller, S., Chane-Woon-Ming, B., Gris, C., Timmers, T., Poinsot, V., Gilbert, L., Heeb, P., Médigue, C., Batut, J., & Masson-Boivin, C. (2010). Experimental Evolution of a Plant Pathogen into a Legume Symbiont PLoS Biology, 8 (1) DOI: 10.1371/journal.pbio.1000280

To intervene or not to intervene: this is a real question

Should land managers actively manipulate the structure and function of ecosystems within protected areas? Is intervention appropriate to protect or maintain native biodiversity and natural processes in areas such as national parks and wilderness areas? These are the questions that stem from a new paper by Richard Hobbs and others in Frontiers in Ecology and the Environment. US national parks and wilderness areas have legislative mandates to maintain ‘naturalness’, but what does this mean in the context of dynamic ecosystems with current and future changes including invasions by nonnative organisms and climate change?

Hobbs and his colleagues challenge concepts of naturalness and propose several ‘guiding principles’ for stewards of national parks and wilderness. They suggest that more useful concepts for managing protected areas relate to ecological integrity and resilience. Concepts of ecological integrity have been adopted by Parks Canada and relate to maintaining ecosystem components. Resilience concepts focus on the ability of a system to “absorb change and persist” without undergoing a “fundamental loss of character”. While maintaining ecological integrity in the face of global changes may - by definition - require protection of species, maintaining ecological resilience tends to focus more attention on ecosystem function “over preserving specific species in situ”.

Rather than protecting an area to maintain naturalness, focusing on ecological integrity and resilience acknowledges that a diversity of approaches - from non-intervention to actively managing systems - may be required. The flexibility in this view, demands that conservation planning span gradients of land uses across landscapes. Management objectives and success need to be re-evaluated in an adaptive and experimental framework, which requires careful and robust monitoring.

At The Wilderness Society and specifically here in Montana, these very questions are being wrestled with in terms of forest restoration, fire management, and climate change. Current forest conditions have been shaped by historic logging practices and fire suppression leading to altered structure and function – including increasing the severity of fires. Through active management, including removing small diameter trees and lighting prescribed fires, managers hope to restore forests and fire intensities to conditions more closely resembling those that historically occurred. Much of the research on restoration was conducted in dry forests in the American Southwest where low-severity fires occurred across large areas. However, in the Northern Rockies, many forests were shaped by a ‘mixed severity’ fire regime, where fires crept along the forest floor in some areas and torched trees in others. In many cases, these forests have not been fundamentally altered and need only the return of fire to restore their resilience. In other cases, forests are recovering from past logging practices and may benefit from thinning to restore a fire-resilient structure.

To return to the paper at hand: what is the appropriate level of intervention to maintain ecological integrity and resilience given past forest management and future climate change? If the current forest lacks integrity (novel stand structure) and resilience under a predicted climate of warmer, drier conditions, what is the appropriate level of management? While The Wilderness Society continues to work with diverse partners to answer these questions, one thing is clear: whatever actions take place, they need to be conducted with humility in an experimental framework that includes sufficient ecological monitoring. For the ‘experiment’ to be most helpful, we should maintain adequate hands-off “controls” along with the “treatments” to allow us to gauge the effects of intervention.

Richard J Hobbs, David N Cole, Laurie Yung, Erika S Zavaleta, Gregory H Aplet, F Stuart Chapin III, Peter B Landres, David J Parsons, Nathan L Stephenson, Peter S White, David M Graber, Eric S Higgs, Constance I Millar, John M Randall, Kathy A Tonnessen, Stephen Woodley (2009) Guiding concepts for park and wilderness stewardship in an era of global environmental change. Frontiers in Ecology and the Environment e-View.
doi: 10.1890/090089
http://www.esajournals.org/doi/abs/10.1890/090089

Timing is everything: global warming and the timing of species interactions

While an obvious affect of climate change will be changes in the distributions or range sizes of species, more insidious and likely more consequential will be how species interactions are affected by changes in the timing of growth and reproduction. These changes in an organism's life cycle, or phenology, can create mismatches between an organism's need and resource availability or the readiness of coevolved partners -such as plants and pollinators.

In an 'Idea and Perspective' paper in Ecology Letters, Louie Yang and Volker Rudolf set out a new framework to examine the effects of phenological shifts on species interactions. They argue that one cannot understand or predict the fitness consequences of a phenology shift without knowing how interacting species' phenologies are also influenced by environmental changes. The consequences of phenological shifts are changes in fitness, and the question is: how would one go about assessing the fitness effects of phenological changes on interactions? This is where this paper really hits its stride. Yang and Rudolf set out a new conceptual framework for studying the fitness consequences of phenological shifts. They make the case that an experimental approach is required to test the three likely scenarios. The first is that there are no changes in phenology -that is, measuring the fitness levels of the two interacting species under stable conditions. Second, you induce an experimental shift in the timing of one of the species. For example, in a plant-herbivore interaction, germinate the plant earlier and when the herbivore normally has access to the plant, the plant will be older. What are the fitness changes associated with this shift? Finally, you can shift the timing of the other species relative to the first. In our example, the herbivore has access to younger plants and again are there fitness consequences?

Yang and Rudolf call the full combination of possible fitness effects, across a number of timing mismatches, 'the ontogeny-phenology landscape'. By mapping fitness changes across this ontogeny-phenology landscape, researchers can offer better predictions, on top of just changes in range size or habitat use, about the possible affects of climate change. The obvious question, and Yang and Rudolf acknowledge this, is how to extend two-species ontogeny-phenology to multi-species communities. Of course, extending two-species interactions to communities is a question that plagues most of community ecology, but I think the solution is that researchers who know their systems often have intuition about the major players, and thus those species where phenology shifts should have disproportionate effects on other species. Such species could be the place to start. Another strategy would be a food web type approach, where species are lumped into broader trophic groups and we ask how shifts in certain trophic groups affect other groups.

Regardless of how to extend this framework to multispecies assemblages, I see this paper as likely to be very influential. It gives researches a new focus and framework, where specific predictions about climate change can be made.

Yang, L., & Rudolf, V. (2010). Phenology, ontogeny and the effects of climate change on the timing of species interactions Ecology Letters, 13 (1), 1-10 DOI: 10.1111/j.1461-0248.2009.01402.x

Plant genotypic diversity supports pollinator diversity

Research over the past 20 years has shown that plant communities with greater diversity maintain higher productivity, greater stability and support more diverse arthropod assemblages. More recently, several experiments have shown that interspecific diversity (namely genotypic differences) also affects community functioning. Pollination is often considered an essential function, and does plant genotypic diversity affect pollinator diversity and frequency?

In a recent paper in PLoS ONE, Genung and colleagues test whether plant genotypic diversity affects pollinator visits. They use an experimental system set-up by Greg Crutsinger that combines multiple genotypes of the goldenrod, Solidago altissima, and record pollinator visits over two years. Experimental plots contained 1, 3, 6, or 12 genotypes of S. altissima. After accounting for differences in abundance, Genung et al. show that as genotypic diversity increases, both pollinator richness and number of visits to the plot significantly increase. This increase is greater than expectations of randomly simulated assemblages combining proportional pollinator visits from monocultures.

The previous research at the species-level has made a persuasive rationale to protect species diversity in order to maintain ecosystem functioning. Now, research like this is making a case that there are consequences for not explicitly considering genetic diversity in conservation planning and habitat restoration.

Genung, M., Lessard, J., Brown, C., Bunn, W., Cregger, M., Reynolds, W., Felker-Quinn, E., Stevenson, M., Hartley, A., Crutsinger, G., Schweitzer, J., & Bailey, J. (2010). Non-Additive Effects of Genotypic Diversity Increase Floral Abundance and Abundance of Floral Visitors PLoS ONE, 5 (1) DOI: 10.1371/journal.pone.0008711

Double or nothing

As I finished my undergrad career and started thinking about graduate school, I was totally infatuated with the chromosomal speciation of treefrogs in the genus Hyla. Hyla versicolor and H. chrysoscelis, the 'gray treefrogs', have similar geographic distributions and look almost identical - except that one is a tetraploid version of the other. The increase in genome size is associated with a slight increase in cell size, which has trickle-down effects into physiology, the sound of their call, and other ecological factors, and of course they are reproductively isolated. As it turns out, Margaret Ptacek and colleagues were unraveling this mystery at the genetic level just as I was learning of it, and while I was disappointed not to be able to explore this for my graduate work, Margaret made up for it by paying for all the drinks when I visited Clemson a few years back.

So it was with considerable interest that I stumbled across one of the first tables of contents of the new year, in BMC Evolutionary Biology. Two co-occurring populations of the diatom Ditylum brightwellii, it turns out, differ in genome size. In this case, the belief is that there is a single taxonomic species harboring a very recent genome duplication polymorphism (which are likely cryptic species). Of course, a species by any other name... well, that's the problem isn't it? In the world of diatoms, according to Koester and colleagues, the 'barcode' standard is to use the 18S rDNA gene sequences and silica cell wall morphology in diagnosing species. However, already armed with evidence that two substantially distinct populations could be identified with the more rapidly-evolving ITS gene region, these researchers explored how differences in reproductive rates and size distributions might be associated with genome size.

See, diatoms are the petri dishes of the natural world. In order to reproduce, each side of the interlocking silica case separates and generates a new nested case. One of the offspring of this fission will be the same size as the parental individual, the other will be slightly smaller - the smaller of the two original cell walls, with an even smaller one nested within. At least that is how I understand it. Over time, these clonal lineages reduce substantially in size, and cell size is eventually limited by genome size; sexual reproduction then allows them to regain a larger cell size and the process repeats. So, the life history of this species requires an interesting interaction among the genome (which places a lower bound on cell size, and a lower bound on reproductive rate) and the population.

In Ditylum, Koester et al. were able to show that there are not only two very distinct genetic lineages, but that the one that is regionally localized to Puget Sound appears to have been generated through genome duplication. That is, there is a cosmopolitan species, and an offshoot lineage that was formed through some form of genome duplication, with concomitant changes in cell size, rates of population growth, and reproductive isolation. Koester et al. conclude that these lineages are cryptic species, and that this form of isolation may be common in marine diatoms.

More generally, this shows another way in which our understanding of biodiversity is changing rapidly thanks to molecular diversity analysis. The latest term to be coined by John Avise, biodiversity genetics, reflects the fact that we must now consider all of the new ways in which this technology can accelerate the rate of discovery in our natural world. Taxonomists trained in the morphology and phenotypic diversity of life are few; certainly too few to keep up with growing scientific collections, and the bottleneck in describing species can be a difficult one for management and conservation. The '18S or bust' approach in diatoms may be one standard that will change as more studies like this one, out of Armbrust's lab at Washington, illuminate how dynamic biological diversity can be.

Predicting invader success requires integrating ecological and land use patterns.

Disclaimer, this was modified from an editorial I wrote for the Journal of Applied Ecology.

In the quest to understand species invasions, we often try to link the abundance and distribution of invaders to underlying ecological processes. For example, oft-studied are the links between exotic diversity and native richness or environmental heterogeneity. Seemingly independently, research into how specific land use or management activities affect invasion dynamics is also fairly common. While both research strategies are of fundamental importance, not often recognized, or at least explicitly studied, is that both ecological patterns and management activities simultaneously affect invasion success. Thus a truly integrative approach to understanding invader success must take into account variation in ecological communities and abiotic resource avalibility as well as land use patterns at multiple spatial scales. Such an approach is necessary if ecologists wish to predict potential invader abundance, spread and impact.

Diez et al. Examine how environmental and management heterogeneity interact to influence patterns of Hieracium pilosella (Asteraceae) inasions in the South Island of New Zealand. The spread of H. Pilosella in New Zealand is threatening native habitats (tussock fields) and the livestock grazing industry. Diez et al. Asked how environmental and management regimes affect H. Pilosella abundance and distribution across six large farms on the South Island. This is an interesting and important question, not just because they are examining how human-caused and ecological variation interact to affect H. Pilosella dynamics, but also because these sources are heterogeneity are realized at different spatial scales.

Diez et al. show that the abundance and distribution of H. Pilosella was significantly affected by the interaction of habitat type (i.e., short vs. tall tussocks) and farm management strategies (i.e., fertilization and grazing rates). At larger scales, H. Pilosella was more abundant in tall tussock habitats and was unaffected by fertilization, while in short tussocks, it was less abundant in fertilized patches. At small scales, H. Pilosella was less likely to be found in short tussocks with high exotic grass cover and high productivity (measured as site soil moisture and solar radiation). Conversely, in tall tussocks, H. Pilosella was more likely to be found on sites with high natural productivity. Diez et al. were able to tease these complex causal mechanism apart by using Bayesian multilevel linear models, for which they included example R code in an online appendix.

While it is a truism in ecology to say that heterogeneity affects ecological patterns, this paper deserves mention because they convincingly show that the spread of noxious exotic plants in a complex landscape, can potentially predicted by understanding the invader success in different habitat types and land management strategies. In their case they show how human activities, which were not designed to affect H. Pilosella, can strongly affect abundance in different habitat types. This type of approach to understanding invader dynamics can potentially arm managers with the ability to use existing land use strategies to predict how and where further invader targeting would be most useful.


Diez, J., Buckley, H., Case, B., Harsch, M., Sciligo, A., Wangen, S., & Duncan, R. (2009). Interacting effects of management and environmental variability at multiple scales on invasive species distributions Journal of Applied Ecology DOI: 10.1111/j.1365-2664.2009.01725.x

1st anniversary!

The Eeb and Flow is now a year old. Thanks to all our contributors and we hope readers will continue to find our posts interesting, informative and timely. Hopefully, with sustained effort on our part, we can surpass the 20,000 reads from this year and make 2010 a great year for readers and contributors.

Thanks!

Parasite competition enhances host survival

Contracting a parasite is bad. But is getting colonized by multiple parasitic species worse? This is an interesting and important question. The host is a resource, which can support a limited number of parasitic individuals, and so how does competition affect parasitic species and host mortality?
This was the premise of a recent paper by Oliver Balmer and colleagues, studying trypanosome infection of mice hosts. They engineered two transgeneic strains of the protozoan parasite, Trypanosoma brucei (African sleeping sickness), to fluoresce different colors in order to assess infections. They infected mice with each strain separately and together and measured host survival and parasite density.

They found that when both strains were present, they competitively suppressed each other and that the level of suppression depended on the initial density of each strain. One of the strains was more virulent than the other, and infection by both strains reduced mortality by 15% compared to infection by the virulent strain only. This is due to the suppression of the virulent strain by the low virulent strain.

The authors argue that strain source and intraspecific genetic diversity can have an important effect on host mortality. I would also argue that understanding interspecific interactions and within-host niche differences, would also be critical.

What a cool use of molecular technology to test basic hypotheses about disease ecology.

Balmer, O., Stearns, S., Schötzau, A., & Brun, R. (2009). Intraspecific competition between co-infecting parasite strains enhances host survival in African trypanosomes Ecology, 90 (12), 3367-3378 DOI: 10.1890/08-2291.1

Understanding wildlife-friendly ecolabels

These days, it seems like nearly everything in the supermarket is good for the environment in one way or another. Over the past decade, more and more companies have started using ecolabels to collect a premium on products that claim to contribute to environmental protection.

But not all ecolabels are created equal. The credibility of their claims varies widely, ranging from environmentally meaningful to downright exploitative.

A recent study by Adrian Treves and Stephanie Jones provides a model for policy-makers and consumers to discriminate between claims.

“In a nutshell, [we] were looking for a way to analyze this cloud of ecolabels out there, all of them claiming to be the best thing for a given species or the best thing for a given ecosystem,” said Treves in an interview.

In the early stages of their research, Treves and Jones realized that wildlife friendly ecolabels can be split along the same lines that have divided debating groups of conservationists. They drew upon these divergent perspectives to partition wildlife friendly ecolabels into three categories.

“Supportive” ecolabels such as Endangered Species Chocolate donate some percentage of revenues to conservation organizations. Verifying the claims for this category is compromised by the transfer of funds to a third-party recipient who is usually not accountable to consumers.

“Persuasive” ecolabels claim to improve production methods in a way that eliminates threats to wildlife, but do not assess actual conservation of wildlife. Although the persuasive category is more transparent and environmentally effective than the supportive one, this type of ecolabel bases its certification requirements on assumptions about threats to wildlife without testing how reduction of perceived threats impacts wildlife. Tuna labeled as Dolphin Safe is an example of a persuasive ecolabel.

“Protective” ecolabels certify wildlife conservation by assessing whether reduction of threats enhances wildlife populations. The Marine Stewardship Council certifies fisheries under a protective ecolabel. This category is the most meaningful to wildlife because it matches the recommendations of the latest conservation science. By following the scientific method, protective ecolabels can verify that they actually help humans and wildlife coexist.

Just as conservation is often pitted against economic interests like agriculture or development, ecolabels must balance a trade-off between consumer confidence and producer incentive.

Protective ecolabels gain the most consumer credibility but also require the greatest verification effort. Proving that producers conserved wildlife is costly, time-consuming, and logistically challenging. Wild animals habitually ignore property boundaries and can die or disperse for reasons unrelated to producer activities. Often, the costs associated with these challenges outweigh the economic incentive of being labeled as “green.”

Treves, A. and S. M. Jones. 2009. Strategic trade-offs for wildlife-friendly eco-labels. Frontiers in Ecology and the Environment. DOI:10.1890/080173

(Image courtesy of kateboydell at flickr under a Creative Commons license)

Taking below-ground processes seriously: plant coexistence and soil depth

Some of the earliest ecologists, like Eugen Warming and Christen Raunkiaer, were enthralled with the minutia of the differences in plant life forms and how these differences determined where plants lived. They realized that differences in plant growth forms corresponded to how different plants made their way in the world. Since this early era, understanding the mechanisms of plant competition is one of the most widely-studied aspects of ecology. This is such an important aspect of ecology because understanding plant coexistence allows us to understand what controls productivity in the basal trophic level for most terrestrial food webs. There are a plethora of plausible mechanisms for how plants are able to coexist, and most involve above-ground partitioning strategies (such as different leaf shapes) or phenological differences (such as germination or bolting timing). Yet, below-ground interactions among plants as a way to understand competition and coexistence have been making a strong resurgence in the literature lately. This resurgence has been driven by new hypotheses and technologies.In what is probably the best hypothesis test of the role for below-ground niche partitioning, Mathew Dornbush and Brian Wilsey reveal how soil depth can affect coexistence. They seeded 36 tallgrass prairie species into plot that were either shallow, medium or deep soiled, and asked if species richness and diversity were affected after 3 years. They found that species richness significantly increased with increased soil depth, revealing that deeper soils likely had greater niche opportunities for species. Not only did deeper soils harbor greater richness, but compositions were non-random subsets. The species inhabiting shallow soils were a subset of medium soils, and medium a subset of deep. This means that increasing depth opened new niche opportunities, unique from the ones for shallow soils.

This study is the first field-based experiment of soil depth and coexistence, that I know of and the results are compelling. Plant species are segregating below-ground niches, and perhaps we look for other partitioning strategies for species that inhabit the same soil depth.

Dornbush, M., & Wilsey, B. (2009). Experimental manipulation of soil depth alters species richness and co-occurrence in restored tallgrass prairie Journal of Ecology DOI: 10.1111/j.1365-2745.2009.01605.x

Other notable recent papers on below-ground processes:

Bartelheimer, M., Gowing, D., & Silvertown, J. (2009). Explaining hydrological niches: the decisive role of below-ground competition in two closely related species Journal of Ecology DOI: 10.1111/j.1365-2745.2009.01598.x

Cramer, M., van Cauter, A., & Bond, W. (2009). Growth of N-fixing African savanna species is constrained by below-ground competition with grass Journal of Ecology DOI: 10.1111/j.1365-2745.2009.01594.x

Meier, C., Keyserling, K., & Bowman, W. (2009). Fine root inputs to soil reduce growth of a neighbouring plant via distinct mechanisms dependent on root carbon chemistry Journal of Ecology, 97 (5), 941-949 DOI: 10.1111/j.1365-2745.2009.01537.x

Beware of the fake conference

I don't know about other researchers, but I get inundated with e-mails about upcoming conferences from organizations I've never heard of, on topics that, at best, only tangentially relate to my work. I think that most of these are put on by for-profit groups that try to cash in on hot topics. But now there are truly fake conferences that are fronts designed to get your financial information. In a new post by Bob Grant on The Scientist news blog, he relays a detailed example of such a scam conference. He went so far as to contact the venues and speakers listed by the scammers, and of course none of those listed had ever heard of the conference. The ultimate enticement was the offer to pay for travel expenses, and the presumption is that they would offer to reimburse you, but need your bank account information. The evolvability of internet scammers is truly impressive.

Something fishy

Of the many victories wrought by DNA barcoding - the ability to place an unknown sample in a phylogenetic, and often taxonomic, context using short fragments of DNA sequence data - some of the most useful applications for management have come from the sea. One of the best citation-to-data ratios in this regard belongs to a 2004 study by Peter Marko. This project extended naturally from Marko's molecular ecology course: students purchased samples of "red snapper" from various fish markets, and sequence data from the mitochondrial cytochrome b gene region showed that most of these specimens were not, in fact, Lutjanus campechinus - they were often understudied and probably rare relatives, or in some cases not snapper at all. The conservation implications from this study were huge, and a number of papers have followed suit, looking at a variety of similar systems. If you aren't interested in adding to your list of papers to read, check out the short film based on work done in Steve Palumbi's lab that documents their work to identify shark fins.

In a paper by Lowenstein et al., published last week in PLoS ONE, the focus was on sushi, specifically tuna. The common labeling errors were caught again: there were mismatches between what restaurants called the fish, and what was actually being offered. In some cases, very phylo-distant species are being sold as "tuna", and these species can actually make consumers ill. The story is an interesting one of how fraud develops in samples of organisms that can no longer be visually tied to the species they came from, and the difficulties in protecting consumers from fraud under current regulations. Obviously, the perils of overfishing are becoming quite clear and interested readers should carry their Monterey Bay Aquarium seafood guides or similar (there's even an iPhone app for that!) with them before ordering at restaurants.

A particularly interesting advance in this study was taking the barcoding approach beyond the visual appeal of tree-building and similarity with databased sequence data. One concern about barcoding has been that even when a new clade appears in a phylogeny, taxonomy cannot be updated without some sort of diagnostic characters. It is uncommon for new species (especially of animals) to be described based on DNA sequence data alone, but it is nevertheless the norm to define the character states that uniquely define a species from its relatives. In Lowenstein et al.'s paper, they identified 14 diagnostic DNA substitutions that could be used to uniquely identify all species of Thunnus and suggested that focusing on particular characters within the "barcode gene" (mitochondrial cytochrome oxidase I) will also be necessary for new technologies to accelerate in-the-field identification.

This latter step is of interest for anybody interested in cryptic species, or identifications when other reference material is not available. I hassled one of my former Ph.D. students endlessly as she revised her dissertation because we had been comfortably using a phylogenetic tree to assign unknown individuals to one of three cryptic taxa (in the isopod genus Idotea), but prior to publication we knew that diagnostic characters would be necessary for subsequent work to be readily comparable. And, since the undergraduate evolution lab at the University of Georgia repeats Marko's work on red snapper every few years (the local Kroger now knows not to advertise their special on "red snapper from Indonesia"), perhaps the lab can be extended by having the students generate these characters for the genus Lutjanus as well. I don't seem to have any problem convincing students to do their homework when it involves going out for sushi.

Ross Crozier, evolutionary biologist and conservation biologist

Sadly, one of Australia's leading evolutionary biologists, Ross Crozier passed away suddenly last week (Nov. 12th, 2009). As a Professor at James Cook University, he worked on a plethora of evolutionary issues, from understanding the evolution of sociality in insects to population genetics and molecular phylogenetics. To my mind, his most influential papers were on how we can use patterns of evolutionary history in guiding conservation decisions -the agony of choice. While he promoted the conservation of phylogenetic diversity, per se, his great insight was that even comparing species that are relatively divergent does not mean that they are equally valuable, and we should consider information content as well. That is, a species with 80,000 genes is more valuable than a species with 20,000 genes, since the 80K-gene species has greater information content.

"Differences in the information content of genomes led to the realization that, other things being equal, some organisms have intrinsically higher conservation worth than others." -Ross Crozier

Ross also recently was the handling editor, at Ecology Letters, on a paper of mine and his insights and support were greatly appreciated and helped to improve our manuscript in numerous ways.

Here are my two favorite papers of his.

Crozier, R. H. 1992. GENETIC DIVERSITY AND THE AGONY OF CHOICE. Biological Conservation 61:11-15.

Crozier, R. H. 1997. Preserving the information content of species: Genetic diversity, phylogeny, and conservation worth. Annual Review of Ecology and Systematics 28:243-268.

Eutrophication and fish depletion add up

The Baltic Sea is the world’s biggest brackish water body. The main threats for this unique ecosystem are eutrophication and overfishing. In coastal ecosystems eutrophication is considered to be the main factor causing the observed regime shift from long living canopy forming macroalgae towards systems dominated by ephemeral filamentous algae. Canopy forming macroalgae build nursery habitat, store nutrients, decline turbidity, and enrich water with oxygen whereas ephemeral algae can build large scale floating mats causing hypoxia and increase turbidity. Loss of top predators is known to cause trophic cascades. In the simplest scenario top predator loss means an increase in mesopredators, a decrease in grazers and thus an increase in algae growth. There is growing evidence that nutrient related algae blooms are not independent of top-down regulation. However, both threats, eutrophication and overfishing, are so far managed independently of each other by focusing either on reducing nutrient loads or defining fishing quotas for threatened species.

In a combined study using field data and evidence of two experimental studies Eriksson et al. show that decline of top-predators and nutrient load have similar and additive effects on the abundance of ephemeral algae. Both factors together increased abundance of ephemeral algae many times! The field data revealed a strong negative correlation between the abundance of fish and ephemeral algae. When fish was depleted high abundances of their prey and at the same time high cover of ephemeral algae was observed. The experiments very nicely proofed these observations. By excluding predatory fish Eriksson et al. show that (i) the abundance of small mesopredators increased, (ii) the smaller gastropod grazers became smaller, and (iii) the net production of ephemeral algae increased. Moreover, the predator effect depended on grazers and habitat complexity. In the absence of grazers predator removal had no effect on algae growth. In the absence of canopy cover, i.e. a proxy for habitat complexity ephemeral algae growth doubled.

This paper makes a strong point that to successfully combat eutrophication the so far unidirectional view on either bottom-up or top-down forces should change towards an integrated approach taking into account both factors.


Britas Klemens Eriksson, Lars Ljunggren, Alfred Sandström, Gustav Johansson, Johanna Mattila, Anja Rubach, Sonja Råberg, Martin Snickars (2009) Declines in predatory fish promote bloom-forming macroalgae. Ecological Applications: Vol. 19, No. 8, pp. 1975-1988. doi: 10.1890/08-0964.1

Podcasts from the Center

Looking for interviews with scientists and managers working on important ecology and conservation issues? Luckily, a new project, called the Voyage of the Beagle has recently started archiving interview podcasts. Jai Ranganathan, a postdoctoral associate at the National Center for Ecological Analysis and Synthesis started this site to promote current research and researchers and to make lively conversations about research accessible to everyone. Check it often, three new interviews will be posted every week!

The latest podcasts are fed into our blog roll on the right sidebar.

Emergent linkages in seemingly unconnected food chains

Food webs are notoriously complex, and a difficult aspect of ecology is to offer a priori model-derived predictions of food web processes. There are some ecologists, such Neo Martinez and Jordi Bascompte, who have advanced our understanding of the general mechanisms of food web properties and dynamics through tools such as network theory. Such advanced approaches rely on direct interactions among species, or at least indirect interactions that are mediated through changes in abundance of different network players. However, what is missing from our general understanding of food web interactions is the role that behavioral responses can affect patterns of consumption and network connectivity.

Washington State University ecologists, Renée Prasad and William Snyder convincingly show how behavioral responses to predation can fundamentally alter food web interactions and link previously independent predator-prey interactions. They used two spatially independent insect predator-prey links in a novel, factorially-designed experiment. The two food chains consisted of a ground-based one, where ground beetles consume fly eggs and a plant-based one, where green peach aphids feed on the plants and are consumed by lady beetles. Under the ground-based chain only, the ground-based chain plus aphids, or ground-based chain plus lady beetles, the ground beetles consume a high proportion of the fly eggs. However, when both aphids and lady beetles are present, aphids respond to lady beetles by dropping off the plants and the ground beetles switch from consuming fly eggs to aphids. Under this last treatment, very few fly eggs are consumed, fundamentally altering the strength of the linkages in the two food chains and connecting them together.

This research highlights the inherent complexity in trying to understand multispecies systems, where the actors potentially have behavioral responses to other species, changing the nature of interactions. These types of responses may also generally increase the connectedness of such networks, which may result in more stable food webs, but this would need to be empirically tested. Regardless, this type of experiment offers food-for-thought to scientists trying to work general processes into a broad understanding of food web dynamics.

Prasad, R., & Snyder, W. (2009). A non-trophic interaction chain links predators in different spatial niches Oecologia DOI: 10.1007/s00442-009-1486-7

Eco-label Promotes Biodiversity on Farms

At first glance, potato farms might seem like an unlikely candidate for conservation efforts.

But Wisconsin researchers are demonstrating that biodiversity can be restored even in the midst of large-scale farming.

Paul Zedler, professor of Environmental Studies at the University of Wisconsin (UW)-Madison, and his colleagues are working with potato farmers to restore pre-settlement habitats on growers’ lands.

In central Wisconsin, 42,600 acres are devoted to potatoes. Since the landscape is dominated by agriculture, some proportion of farmland must be set aside for conservation to preserve biodiversity in this part of the state.

Restoration is a requirement of the Wisconsin Healthy Grown potato program, a partnership between UW–Madison, the Wisconsin Potato and Vegetable Growers’ Association, and NGOs such as the International Crane Foundation, Defenders of Wildlife, and the World Wildlife Fund.

The groundwork for the Healthy Grown program was laid out in the 1980s, when a group of potato growers voluntarily discontinued use of the high-risk pesticide aldicarb. The farmers turned to UW-Madison researchers for pest-management advice. This grassroots movement eventually drew attention from conservation agencies.

To be certified under the Healthy Grown eco-label, potatoes must be grown under a set of standards that restrict pesticide and fertilizer use. The program was able to draw from an extensive body of UW-Madison research to guide the formulation of these in-field standards. But farmers and environmentalists were interested in doing more.

Since the program's conception, growers had expressed interest in managing their farms as whole ecosystems rather than just focusing on crop production on a field by field basis. At the same time, the NGOs saw the program as an opportunity to bring farmland into regional-scale conservation plans.

Satisfying this interest in developing a conservation standard for the eco-label was challenging for researchers because fewer precedents existed. Even the largest and most well-known eco-label, USDA Organic, does not include a conservation requirement in its certification standards.

Zedler and his colleagues looked to the Nature Conservancy, which had established a system for making strategic conservation decisions and measuring conservation success at sites where the objective is to improve biodiversity on whatever land can be spared from intensive human use.

Potato farms in central Wisconsin are unusual in their tendency to contain significant patches of marginal land without crops because these patches cannot be irrigated – a necessary factor in growing potatoes. The result is a complex mosaic of land in which remnant patches of disturbed natural habitat are isolated within an agricultural matrix. Zedler and his colleagues focused their research efforts on these patches of non-crop land.

Their research suggests that prescribed burns and control of invasive plant species can help restore disturbed non-crop land to the habitats that characterized central Wisconsin before European settlement: prairie, oak-pine savannah, and sedge meadow.

Thus far, the Healthy Grown program has restored more than 400 acres of privately owned farmland. According to Zedler and his colleagues, farmers’ strong ties to their land motivate their commitment to the conservation standard of the Healthy Grown eco-label.

Zedler, P. H., T. Anchor, D. Knuteson, C. Gratton, and J. Barzen. 2009. Using an ecolabel to promote on-farm conservation: the Wisconsin Healthy Grown experience. International Journal of Agricultural Sustainability 7(1): 61-74. DOI:10.3763/ijas.2009.0394

(Image courtesy of FotoosVanRobin at flickr under a Creative Commons license)

Time management for grad students and researchers

As researchers, we all have incredible demands on our time. These demands can quickly snowball, leaving us feeling like things are out of control. This lack of control over your priorities and responsibilities can lead to anxiety and depression and perhaps to dropping out of graduate school. Getting control and developing good time management skills can go a long way towards preserving your sanity and making grad school and a career in academic research enjoyable. All it really takes is planning, and knowing the things to plan for. The critical priorities that every student and/or researcher must plan, includes:

• Writing/outlining research questions
• Taking courses
  
• Teaching
• Appointments with supervisor and committee
• Design/set-up experiments/studies
• Data collection
  
• Analyzing data
  
• Writing papers/chapters/articles
  
• Rewriting papers/chapters/articles
  
• Meetings/presentations
  
• Finding a publisher/lay out/submitting manuscripts
  
• Administrative duties
• Holidays
  
• The unexpected!

All these things tugging at you all at once can make it difficult to start any single thing -because you feel the anxiety about not starting other things. Here are seven strategies for controlling your time and priorities, and helping you to cope with time stress.

1 - Live by the calendar, die by the calendar. Basically, schedule everything. With freely available calendars like Google's or Sunbird there is no reason to not adopt a calendar. Web-based calendars, mean you can be anywhere, on any computer and still have access. Be sure to share the calendar with lab mates and professors, so they know when you are booked. Schedule everything from meetings, to large slots of time dedicated to time-intensive things like reviewing a manuscript or data analyses.

2- Gimme a break! Working for four straight hours without a break will cause you to be less productive, than four hours with a 5 minute break every 40-60 minutes. Don't be afraid to get up from your desk in between tasks to reset your brain. You could also call or chat with someone, make a coffee, watch a Daily Show clip, update your Facebook status, etc. Don't feel guilty about the 5 minute solitaire game (only about the 2 hour ones).

3- Leave. Have a secret work spot. It could the back corner of a library, a coffee shop, home, or some special place. The point is to have a productive site where you are not tempted to do nonproductive things when you need to be focusing on a task. Leave your e-mail behind if possible and do not let colleagues know where you are. Make it your time.

4- Delegate. You do not need to do everything yourself. If you are collaborating, don't be afraid to ask collaborators to do something. If you are at a big university, search for undergrad volunteers to help out. If you are really swamped, ask a friend to help out with an experiment.

5- Write it down or lose it. I write down everything, and I do it for two reasons. First, I will forget it if it is not written down in front of me (which saves me anxiety about forgetting things). Secondly, these notes become defacto to-do lists which saves me time from having to think about what to do next. If I have ten minutes before a meeting and my list has me e-mailing someone, then I get the reward of ticking something off the list.

6- Enough is enough. Remember, it will never be perfect. Likely, the 13th draft of paper is not appreciably better than the 12th. Plus, reviewers will ALWAYS recommend revisions and you will never win a literary award for it. So if you pour your soul into a manuscript and take 2 years to write it, likely you'll be devastated when you are asked for major revisions. The important thing is getting it submitted and learning when enough is enough can go a long way toward freeing up valuable time.

7- Have fun. Likely, you got into research because you love science. If your work is tedious and boring, find some fun research to offset it. If you have to choose between two projects, and one seems like it will be personally more enjoyable, go for that one. Don't be afraid to shelve a unrewarding project for one that is fun and exciting. Most importantly, reward your self! When you submit a paper, take the rest of the afternoon off. When you finish an intense summer of field work, go to the beach for four days. Tell your close colleagues when you get a paper accepted or an award -you are not bragging, and they will always say 'congrats' or 'awesome', which feels nice. Whatever works as a reward, use it.

Remember, at the end of the day what matters is getting papers out and being a good collaborator/student/mentor/human being. Control of priorities and successful time management will make it a lot easier to get those papers out and be a relaxed, good person to be around.

Conscientious conservation?

A colleague once said at a bar that she didn't believe in "conservation genetics". I'm not quite sure which aspect she was disputing, but one certain conflict is between gearing research toward conservation, while watching chemicals and consumables go into the waste stream. Most of the reactions in my lab are done using pipet tips and tubes made of virgin polypropylene. Nobody wants to recycle this stuff - even though 99% of the chemicals we use are fairly meek reagents like ethanol, water, nucleotides, and barnacle DNA, there's just no way to guarantee the waste stream coming from a building that does molecular research (e.g. you'd probably balk if that plastic got melted down and used for toys). Researchers have enough problems with reactions going wrong to also worry about whether their supplies are contaminated with the products of reactions past. Still, we have to constantly consider how we can minimize waste in the lab.

Lab Waste from Eva Amsen on Vimeo.

As a marine biologist, I'm also very conscious where all this plastic eventually ends up. I'm entertaining ideas for tip and tube recycling, though it is barely worth the effort for a single lab to do so: my lab probably consumes about 10kg of virgin polypropylene a year, into the trash. Super bummer. But that recycling effort could be balanced out if I just got my entire lab (including me) to stop drinking so much soda! Better would be to find institutional solutions, and we're a long way off on that.

Of course a lab is more than plastic. There are chemicals - which we've chosen to avoid some of the nastier ones, like ethidium bromide (using Ames-tested GelRed instead), isotopes (fluorescent-labeled primers), but still must use a little bit of polyacrylamide and a few other things in very small quantities that you wouldn't want to put in a smoothie. There are heating and cooling costs, which we can't do a lot about in our grumpy 1980's-era building at the University of Georgia (we'll assume that under budget constraints physical plant is doing what they can in that regard, though we did install some motion sensors on lights in the auxiliary rooms).

And then, there are all the gizmos. For the holidays I got a fun gift: a Kill-A-Watt. As procrastination during grant writing, I decided not only to check the energy consumption of things at home, but things in the lab. I don't know whether I believe paying to balance carbon emissions works (though at $3/month, I do it anyway), but it is interesting to know what the footprint of a lab like mine is. To make a long story short, it's mostly about the computers. Each computer in my lab used around 5kWh/day - up to $150 in annual energy bills, and actually the only things that compete with computers are my big chromatography fridge and my ultracold freezers (the -80° will use around 6000kWh/year!). Anyway, by unplugging some things that weren't being effectively used - one of the refrigerators, some water baths, an incubator, 2 of the computers - and ensuring that the rest were using the most appropriate power-saving settings - I cut the kWh consumption of my lab (only counting plug-in stuff) by over 10%.

The question is, how does this energy usage affect the science? One could argue that my research program hasn't expanded to fill the resources I had available, or that I can only cut back to the detriment of productivity. Only time will tell! We may have to devise a metric for productivity per kWh - but right now if I calculate my Hirsch index per kWh, it is not the thrilling kind of number I want to run to the administration with. I better get back to work.

Fall colors redux

For those of us in temperate deciduous regions, now is the time of landscapes splashed in red, orange and gold. Here is a link to a post I wrote back in March about the evolutionary meaning of autumn colors. It seemed appropriate to dig it up.

Adaptation and dispersal = (mal)adapted

Ever since Darwin, we often think of organisms as being in a constant battle against other organisms and local environments. Thus natural selection and the resulting arms race results in organisms highly adapted to local conditions and against local antagonists. At the same time, and especially driven by theoretical advances in the 1990's, researchers began to ask how dispersal -that is, the flow of genetic material from elsewhere, can disrupt local adaptation. On the one hand it may provide genetic variation allowing for novel solutions to new difficulties. On the other hand, dispersal may reduce the prevalence of fitness-increasing genes within local populations.

In a simple but elegant experiment, Jill Anderson and Monica Geber performed a reciprocal transplant experiment, moving Elliott's Blueberry plants between two habitats. One population was from highland, dryer habitats and the other from moist lowlands. They further evaluated performance in greenhouse conditions. Their results, published in Evolution, show that these two populations have not specialized to local conditions. Rather, due to asymmetric gene transfer, lowland individuals actually performed better when planted in highlands than compared to their home habitat. Further, in the greenhouse trials, lowland species did not perform better under higher moisture conditions. While genetic or physiological constraints may also limit adaptation, Anderson and Geber present a fairly convincing case that gene flow is the culprit.

These results reveal that populations may actually be relatively mal-adapted to local conditions, which has numerous consequences. For example, we need to be cognizant of adaptations to particular conditions when selecting populations for use in habitat restoration and when trying to predict response to altered climatic or land-use conditions. Importantly what does this mean for multi-species coexistence? Dispersal seems to limit the ability to adapt, and thus, better use local resources or maximize fitness, making for a better competitor. At the same time, dispersal can offset high death rates, allowing for the persistence of a population that would otherwise go extinct. Understanding how these two consequences of dispersal shape populations and communities is an interesting question, and work like Anderson and Geber's provides a foundation for future studies.

Anderson, J., & Geber, M. (2009). DEMOGRAPHIC SOURCE-SINK DYNAMICS RESTRICT LOCAL ADAPTATION IN ELLIOTT'S BLUEBERRY (

)
Evolution DOI: 10.1111/j.1558-5646.2009.00825.x

Mycorrhizal Networks: Socialists, capitalists or superorganisms?

Mycorrhizal networks – fungal mycelium that colonize and connect roots of one or more plant species – are a very intriguing type of fungal-plant association. There is evidence of substantial facilitation between plant individuals via these fungal networks. This can have drastic implications for our understanding of nature, given that the common perception is that other mechanisms, like competition, herbivory or dispersal, are the main drivers of plant community associations. This may be far from reality if the existence of “socialist” networks is widespread (e.g. the ability to connect and profit from a network may be more important than competitive abilities). In the last issue of the Journal of Ecology ( that has a very interesting special feature on facilitation in plant communities), Marcel Van der Heijden and Tom Horton conducted a review of the topic. They found a general positive effect of mycorrhizal networks on seedlings and large plants (i.e. plants tend to grow better if they are associated with a network). However, the reviewers also found some networks can have a neutral or even a negative effect on plants. The plant responses were highly variable depending on other variables including fungal species, nutrients availability, and plant identity. The positive effect of some fungal networks on seedlings growing nearby adult trees of its same species is somehow opposite to the predictions of the Janzen-Connell hypothesis. We need further studies to understand the overall importance of mycorrhizal networks in relation to other better understood mechanisms.

van der Heijden, M., & Horton, T. (2009). Socialism in soil? The importance of mycorrhizal fungal networks for facilitation in natural ecosystems Journal of Ecology, 97 (6), 1139-1150 DOI: 10.1111/j.1365-2745.2009.01570.x

The making of an open era

With the availability of open access (OA) journals, academics now have a choice to make when deciding where to send their manuscripts. The idealistic version of OA journals represents a 'win-win' for researchers. The researchers publishing their work ensure the widest possible audience and research has shown a citation advantage for OA papers. The other side of the 'win-win' scenario is that researchers, no matter where they are, or how rich their institution, get immediate access to high-caliber research papers.

However, not all researchers have completely embraced OA journals. There are two commonly articulated concerns. The first is that many OA journals are not indexed, in most notably Thomson Reuters Web of Knowledge, meaning that a paper will not show up in topic searches, nor will citations be tracked. I for one do not like the idea of a company determining which journals deserve inclusion, thus affecting our choice of journals to submit to.

The second concern is that some OA journals are expensive to publish in. This is especially true for the more prestigious OA journals. Even though such OA journals often provide cash-strapped authors the ability to request a cost deferment, the perception is that you generally need to allocate significant funds for publishing in OA journals. While this cost may be justifiable to an author for inclusion in a journal like PLoS Biology, because of the level of readership and visibility. However, there are other, new, profit-driven journals, which see the OA model as a good business model, with little overhead and the opportunity to charge $1000-2000 per article.

I think that, with the rise of Google Scholar, and tools to assess impact factors (e.g., Publish or Perish), assessing difference sources for articles is available. The second concern is a little more serious, and a broad-scale solution is not readily apparent.

Number of Open Access journals

Regardless, OA journals have proliferated in the past decade. Using the directory of biology OA journals, I show above that the majority of OA journals have appeared after 2000. Some of these have not been successful having faltered after a few volumes, such as the World Wide Web Journal of Biology which published nine volumes with the last in 2004. I am fairly confident that not all these journals could possibly be successful, but I hope that enough are. By having real OA options, especially higher-profile journals, research and academia benefit as a whole.

Which journals become higher profile and viewed as an attractive place to submit a paper is a complex process depending on a strong and dedicated editorial staff and emergent property of the articles submitted. I hope that researchers out there really consider OA journals as a venue for some of their papers and become part of the 'win-win' equation.