Charismatic Orchids

With an estimated >27,000 species, the orchid family is one of the most speciose plant families within the Angiosperms. At the same time, it harbours a large number of threatened species, making it one of the most vulnerable plant families as well. Due to their spectacular floral diversity, orchids have long attracted wide attention from the general public. The commercial trade in specimens was already established in the nineteenth century after the first orchid from overseas had been sent to London in 1818. Eventually, this resulted in a flourishing industry that comprised collectors, merchant traders and orchid hunters who competed against each other, in often dreadful conditions, to find and extract the precious — and much-coveted — flora from their natural habitats. Specimens from all over the world were sent to orchid markets in London and elsewhere in Europe, where they were sold for considerable (and sometimes absurd) amounts of money, culminating in what has later been described as ‘orchidelirium’, the name given to the Victorian era of flower madness, when collecting and discovering orchids became extraordinarily popular. It was not until the 1920s when the French mycologist Noel Bernard discovered how to propagate orchids from seeds that the orchid mania subsided and the plants became plentiful (and affordable!) in Europe and the U.S.

Apart from their ornamental value, orchids have always attracted great scientific interest as well. Inspired by Christian Konrad Sprengel’s 1793 work Das entdeckte Geheimnis der Natur im Bau und in der Befruchtung der Blumen (The Secret of Nature in the Form and Fertilisation of Flowers Discovered), Charles Darwin was among the first to highlight the striking complexity of orchid pollination. In his book ‘On the various contrivances by which British and foreign orchids are fertilized by insects’, which was first published in 1862 and published again, in a revised version, in 1877, Darwin wrote in meticulous detail about the close functional relationships between the sexual structures of orchids and the insects that fertilize them. Although the book sold only about 6,000 copies before the turn of the century and was therefore – at least from a publisher’s point of view – not a success, it was much praised by botanists. Darwin had noted this himself when he wrote: ‘For since the appearance of my book, a surprising number of papers and separate works on the fertilization of all kinds of flowers have appeared; and these are far better done than I could possibly have effected.’ Judging by the large number of papers on orchid biology published in Journal of Ecology, from which the contents of  this Virtual Issue  were selected, orchids continue to be a rich source of inspiration and great model systems for answering important and timely questions in ecology and evolution.

Bee orchid (Ophrys apifera)

Bee orchid (Ophrys apifera)

The selected papers cover three major fields highlighting the complexity of the orchid life style: reproductive biology, demography and mycorrhizal associations. Additionally, twelve Biological Flora of the British Isles accounts have been included in this Virtual Issue. These Biological Flora accounts not only provide a thorough review of what is known about the distribution and natural history of each of the species they address, but also offer critical reflections about their ecology and conservation. Although Biological Flora accounts aim to be as complete as possible, reading between the lines often reveals important gaps in knowledge, or suggests hypotheses to be tested in future research. Therefore, these accounts may be most valuable in providing an important source of inspiration.

Orchids have a complex life-history and describing the demography of these species can be challenging, tedious and at times even frustrating. Every field biologist who has spent a couple of weeks of his/her life monitoring orchid populations knows that one of the most challenging parts of describing the orchid life cycle is getting a grip on what you can’t see, i.e. the developments that take place underground. Seed germination and protocorm development are notoriously difficult to estimate under natural field conditions. Moreover, more than in any other plant family, mature adult individuals are also able to stay underground for one or more years, a phenomenon better known as vegetative dormancy. Dormancy not only complicates field work, but also has a big impact on data analyses afterwards. At least four papers in this Virtual Issue deal with dormancy and how to integrate it into demographic models (Kéry and Gregg 2003, 2004, Shefferson and Tali 2007; Shefferson and Simms 2007). To make things even more complex, orchids do not only rely on pollinators for completion of their life cycle; they also depend on mycorrhizal fungi. The study of mycorrhizal fungi has now stepped out of its infancy, and it has become increasingly clear as a result of major recent advances that mycorrhizal fungi have a major impact on the distribution (Diez 2007; Jacquemyn et al. 2009, 2012) and demography of orchid populations.

Early spider orchid (Ophrys sphegodes)

Early spider orchid (Ophrys sphegodes)

Despite – and perhaps also because of – these difficulties, orchid demographic studies tend to be the longest demographic studies in ecology and they usually have considerable sample sizes. Mike Hutchings’ study on the demography of the early spider orchid (Ophrys sphegodes) is probably one of the longest plant demographic studies to have been carried out so far (Hutchings 2010). Datasets such as this one are rare, and give unprecedented insights into the demography of the species. With the climate changing at an ever faster rate, this and other long-term datasets will become invaluable sources of knowledge as they instantaneously record how plant populations respond to the changing environment (Robbirt et al. 2011). With the advancement of new data analysis techniques such as matrix models and integral projection models (Jacquemyn et al. 2010; Diez et al. 2014), and the inclusion of eco-evolutionary dynamics in population models (Williams et al. 2015), we are starting to get a better grip on understanding the complex demography of orchids and how it is affected by the environment. Williams et al. (2015), for example, used stochastic integral projection models to investigate whether and how climate change affected the life history of the lady orchid (Orchis purpurea). Their analysis shows that with the increasing frequency of droughts the species will inevitably decline. On the other hand, milder winters and wetter springs will have a positive impact on the long-term viability of populations of the species, so it is still difficult to predict how the species will behave in the future.

Almost 150 years after Darwin published the first edition of his book on orchids, orchids keep on fascinating ecologists and evolutionary biologists. This Virtual Issue of papers published in Journal of Ecology demonstrates the vivid interest of the scientific community in the complex ecological processes that affect the population dynamics of these fascinating species and illustrates how ecologists are advancing our understanding of the ecology and evolution of orchids. We very much hope you enjoy reading these papers brought together in this collection and that orchids continue to be a rich inspiration for future ecological and evolutionary researchers. We also hope that the results of these studies may be of interest to the wider public fascinated by orchids and especially to the practitioners and conservation managers so that they may be used to establish appropriate management regimes that will contribute to the long-term conservation of these species.

Hans Jacquemyn
Associate Editor, Journal of Ecology

Literature cited

Diez, J.M. (2007) Hierarchical patterns of symbiotic orchid germination linked to adult proximity and environmental gradients. Journal of Ecology, 95, 159-170.

Diez, J.M., Giladi, I., Warren, R. & Pulliam, H.R. (2014) Probabilistic and spatially variable niches inferred from demography. Journal of Ecology, 102, 544-554.

Hutchings, M.J. (2010) The population biology of the early spider orchid Ophrys sphegodes Mill. III. Demography over three decades. Journal of Ecology, 98, 867-878.

Jacquemyn, H., Wiegand, T., Vandepitte, K., Brys, R., Roldán-Ruiz, I. & Honnay, O. (2009) Multigenerational analysis of spatial structure in the terrestrial, food-deceptive orchid Orchis mascula. Journal of Ecology, 97, 206-216.

Jacquemyn, H., Brys, R. & Jongejans, E. (2010) Size-dependent flowering and costs of reproduction affect population dynamics in a tuberous perennial woodland orchid. Journal of Ecology, 98, 1204-1215.

Jacquemyn, H., Lievens, B., Brys, R. & Wiegand, T. (2012) Spatial variation in below-ground seed germination and divergent mycorrhizal associations correlate with spatial segregation of three co-occurring orchid species. Journal of Ecology, 100, 1328-1337.

Kéry, M. & Gregg, K.B. (2003) Effects of life-state on detectability in a demographic study of the terrestrial orchid Cleistes bifaria. Journal of Ecology, 91, 265-273.

Kéry, M. and Gregg, K.B. (2004) Demographic analysis of dormancy and survival in the terrestrial orchid Cypripedium reginae. Journal of Ecology, 92, 686-695.

Robbirt, K.M., Davy, A.J., Hutchings, M.J. & Roberts, D.L. (2011) Validation of biological collections as a source of phenological data for use in climate change studies: a case study with the orchid Ophrys sphegodes. Journal of Ecology, 99, 235-241.

Shefferson, R.P. & Tali, K. (2007) Dormancy is associated with decreased adult survival in the burnt orchid, Neotinea ustulata. Journal of Ecology, 95, 217-225.

Shefferson, R.P. & Simms, E.L. (2007) Costs and benefits of fruiting to future reproduction in two dormancy-prone orchids. Journal of Ecology, 95, 865-875.

Williams, J.L., Jacquemyn, H., Ochocki, B.M., Brys, R. & Miller, T.E.X. (2015) Life history evolution under climate change and its influence on the population dynamics of a long-lived plant. Journal of Ecology, 103, 798-808.

Editor’s Choice 103:5

Why aren’t cushion plants always the best facilitators? Consequences of eco-evo processes in alpine systems.

In recent decades facilitation in plant communities has moved from being largely neglected to a well-established phenomenon (Brooker et al. 2008). However, the simple picture of greater facilitation in stressful environments is gradually fading. Not only does abiotic stress change along environmental gradients, facilitators change too. It appears that foundation species such as cushion plants in alpine systems vary in their growth form along environmental stress gradients and exert different effects on subordinate species occupying the cushions (Michalet et al. 2011; Al Hayek et al. 2014). Do cushion plants respond plastically to environmental variation or do they locally adapt to different environments? What are the consequences of plastic and heritable growth form differences for the species attempting to establish inside these cushions? Al Hayek et al. designed a clever reciprocal transplant experiment to resolve these questions and focus on the interface between ecological and evolutionary processes.

The two experimental sites (convex site on the left, and concave site on the right).

The two experimental sites (convex site on the left, and concave site on the right).

They collected distinct individuals of Festuca gautieri from two microhabitats in a subalpine community – tight cushions from dry convex outcrops and loose cushions from wet concave slopes –propagated them in common conditions and reciprocally transplanted them back to convex and concave microhabitats in adjacent common gardens. They found that plants collected from different habitats were morphologically distinct after four years of propagation and grew best in their home environments, suggesting that tight and loose growth forms reflect local adaptation to high-stress and low-stress microenvironments, respectively. However, plants were also highly responsive to their environment and showed plastic changes in multiple traits, towards tight growth forms in high-stress and loose growth forms in low-stress common gardens. Thus, variation in cushion growth form along the stress gradient reflects both heritable differences and plastic responses.

The two phenotypes of Festuca gautieri in their natural habitats at La Pierre Saint Martin (Atlantic Pyrenees, France): tight cushion in rocky convex topography (upper cushion) and loose cushion in concave topography (lower cushion).

The two phenotypes of Festuca gautieri in their natural habitats at La Pierre Saint Martin (Atlantic Pyrenees, France): tight cushion in rocky convex topography (upper cushion) and loose cushion in concave topography (lower cushion).

The results also showed that a high-stress environment generally reduces plant growth and shifts interactions from competitive to facilitative, but it also selects for compact growth forms in facilitators. When seedling survival and richness of establishing subordinate species was examined, it was the loose cushions that showed a facilitative effect on seedlings, while the tight cushions, which are typical of high-stress microenvironments, generally suppressed seedling establishment. In other words, subordinate seedlings get the worst facilitators when they need them most! This raises a question regarding the driving force behind selection for tight growth forms in high-stress habitats. Is it merely due to selection for avoidance of drought stress? Could a tight growth form also be a result of selection for reduced facilitating characteristics and an enhanced ability to physically preclude the establishment of potential competitors?

These are not all of the thought-provoking results that Al Hayek et al. have uncovered. Read on to learn more.

Marina Semchenko
Associate Editor,  Journal of Ecology


Al Hayek, P., Touzard, B., Le Bagousse-Pinguet, Y. & Michalet, R. (2014) Phenotypic differentiation within a foundation grass species correlates with species richness in a subalpine community. Oecologia, 176, 533–544.

Brooker, R.W., Maestre, F.T., Callaway, R.M., Lortie, C.L., Cavieres, L.A., Kunstler, G. et al. (2008) Facilitation in plant communities: the past, the present, and the future. Journal of Ecology, 96, 18–34.

Michalet, R., Xiao, S., Touzard, B., Smith, D.S., Cavieres, L.A., Callaway, R.M. et al. (2011) Phenotypic variation in nurse traits and community feedbacks define an alpine community. Ecology Letters, 14, 433–443.

Some ESA 2015 afterthoughts on Population Ecology, Twitter and BronyCon

The annual meeting of the Ecological Society of America took place a bit over a week ago (Aug 8-14th 2015) in the city of Baltimore, MD. The centennial of largest national ecological society in the world was no joke, and I can’t imagine how much work must have gone behind the scenes for the impeccable conference ESA pulled off, as usual, but this time with over 4,000 delegates. Once again, I initially approached this conference with a “less is more” philosophy… which I rather quickly had to trash as I started browsing online in the ESA conference personal scheduler app, realizing I wish I could produce ramets and send them to different co-occurring talks. This is what my week ended up looking like… pretty sure I wasn’t the only one, based on how many people I saw running from one room to another along that long corridor.

Fig 1_Rob S-G

Fig. 1. A typical (?) ESA schedule: trying to be in four different places at the same time

Indeed, this ESA was packed with plenty of exciting stuff… and the readers of the blog of Journal of Ecology must forgive me for devoting this paragraph to the unexpected partial overlap with another conference: BronyCon. I had just landed in Baltimore, and my jetlag and I were faced with adults and teenagers alike dressed as “My Little Pony” and other fun-looking costumes checking into hotels and taking over the downtown. *I am but left with the question: what do bronies talk about in their meetings? Do they give talks like we do? Are the effects of “My Little Pony” herbivory on prairies a concern to them? Perhaps stamping and fertilization on grassland community composition and diversity? Or the efficiency behind the physiology of flying vs. trotting? Have they implemented a lightening talk format like ESA has (I gave one this year and it was fun)? The only thing I was able to discover (yep, I snuck into their side of the convention center for a coffee from that kilometric queue) was that some of them play Street Fighter-like “My Little Pony”videogames. Interesting, to say the least.

*You are encouraged to read the rest of this paragraph with the narrating voice of Sir David Attenborough in your mind.

Fig. 2. A BronyCon delegate… speechless!

Fig. 2. A BronyCon delegate… speechless!

The opening of the ESA was particularly motivating, as the invited speakers and accomplished awardees did an excellent job at narrating the history of 100 years of progress of American (and international) ecology. It is clear to anybody in ecology that we are finally moving from descriptive to predictive, and that part of that has been facilitated by classical theories, advanced stats, and the “R revolution” (below). A big surprise during the opening was Obama’s video congratulating the Society.

The annual meeting came with a large number of great symposia and organized oral sessions, and population ecology was every where. I particularly enjoyed the lightening talk symposium on “Advances, Frontiers, Applications, and Challenges within and Across Ecological Disciplines: A Celebration of ESA’s Centennial, and a Roadmap for the Next 100 Years”. Deborah Goldberg, recently honored as Eminent Ecologist virtual issue in Journal of Ecology, gave a killer talk on the past, present and some suggestions for future directions for community ecology… all of that in 5 minutes and on auto-advanced slides!

The conference was full of events I wasn’t able to attend, and I must highlight very especially the workshops put together by Naupaka Zimmerman and collaborators on R for intro-users, R for community ecology analyses, and R for scientific plotting. The reason I couldn’t attend those is that my colleagues and I were busy running two workshops on comparative demography with the recently launched new version of COMPADRE, and another on integral projection models. There seems to be quite a bit of interest in demography at large and population ecology in specific at ESA, as showcased by two organized oral sessions. One of them, co-organized by Norma Fowler, Tom Miller, Eelke Jongejans and myself, now offers the scripts used to develop the science behind the talks fully open access. Our hope is that the usage of this tool in novel ways to address a wide repertoire of ecological and evolutionary questions will trigger other potential users’ imagination to use it even in more creative ways.

Fig. 3. Orou Gaoue (Univ Hawai’i) explains his approach to model the demographic effects of on non-timber forest products at the individual level at our “Demography gone wild: applications of integral projection models in molecular ecology, functional ecology, community ecology and conservation biology”.

Fig. 3. Orou Gaoue (Univ Hawai’i) explains his approach to model the demographic effects of on non-timber forest products at the individual level at our “Demography gone wild: applications of integral projection models in molecular ecology, functional ecology, community ecology and conservation biology”.

The symposium on “A century of structured population models in ecology” organized by Hal Caswell and Andre de Roos was a must-attend and it was packed. This event contained some very interesting new ramifications of structured population models for microbes, dispersal, individual heterogeneity, sex-ratio evolution and infectious diseases, to mention a few, given mostly by early career researchers (e.g., Kristen Hunter-Cervera, Will Petry, Jess Metcalf, Allison Shaw).

Other events I highly enjoyed included an organized poster session on “Drones for Ecology: New Sampling Tools for Personal Remote Sensing of Ecosystems”, the symposium “Scaling in Ecology: Building a Synthetic and Predictive Science for the Next 100 Years” organized by Brian Enquist et al., and several presentations by other early career ecologists on “Modeling stochastic within-host pathogen growth to predict host growth and life history tradeoffs” by Arietta Fleming-Davies, “Linking nutritional condition to population performance in a shifting climate: Approaching the holy grail” by Thomas Stephenson, and “Low-assumption fitting of interaction kernels: Spline models for neighborhood competition” by Collin Edwards. The latter constitutes what I think is a breakthrough in the way we incorporate inter- and intra-specific relationships in population models; it seems a rather computational demanding approach, based on splines and IPMs, but I can’t wait to read the publication once it comes out (I hope that the authors send it to Journal of Ecology!).

Final thought: I am not sure if this is now an ESA conference official policy, but in a series of organized oral sessions and symposia, the presider reminded the attendees that we should assume that the presenters would prefer not to have their presentations photographed or tweeted –unless otherwise stated by the speaker– and to act consequently by not taking photos or using Twitter… in my humble opinion**, this is a (huge) step backwards, and a rather anachronistic one, if we consider the recent foundation of the Open Science Section of the ESA. Just as with the principle of presumption of innocent, I humbly suggest that open-access should be the default assumption, unless the author explicitly asks not to take photos/tweet about the presentation. An opt-out option could be made available in the online abstract submission, or perhaps a symbol could be created to append to the talks so it is visually obvious to the attendees when not to photograph/tweet about the talk. After all, in most cases, why else would one present one’s research at the largest national ecological conference like ESA, but to get the word out?

**This is my very own opinion, and in no way it represents necessarily the views of the BES or Journal of Ecology.

Fig. 4. Some tweets on the no-photo/no-tweet controversy at ESA.

Fig. 4. Some tweets on the no-photo/no-tweet controversy at ESA.

Next year, the ESA takes place in Fort Lauderdale. I’m already looking forward to the trip to Florida and to keep on engaging with such a vibrant community of ecologists around the world! Hopefully no announcements will be necessary on photos/twiter. Too bad that BronyCon will not take place there… will we at least get a One Direction concert too?!

Rob Salguero-Gómez

Associate Editor of Journal of Ecology

The Eco-evolutionary Dilemma

This is a guest post by Associate Editor Richard P. Shefferson, who recently also guest-edited a Special Feature for Journal of Ecology.

The most recent issue of Journal of Ecology (July 2015) includes a Special Feature on Eco-evolutionary Dynamics in Plants. The Special Feature consists of five research papers and an editorial, and the themes covered include genetic variation (Shaw et al., 2015, Lamit et al., 2015), adaptive plasticity (Metcalf et al., 2015), community structure (Lamit et al., 2015), herbivore evolution (Utsumi, 2015), inbreeding (Shaw et al., 2015), density dependence (Williams et al., 2015, Metcalf et al., 2015)and climate change (Williams et al., 2015), all from the eco-evo perspective. Although this is not the first special issue of a major ecological journal on this topic, it is nonetheless the first to highlight the role of and opportunities offered by plant ecological research in this rather new field.

The essential realization that has led to the development of this sub-discipline of evolutionary ecology is that evolution is not necessarily slow, as has often been supposed by both ecologists and evolutionary biologists alike, but that it may be – and actually often is – quite rapid. In fact, as many others have pointed out, it is rapid enough to occur at the same pace as many other ecological processes (Hairston Jr. et al., 2005). This overlapping timescale yields more questions than answers, and causes a fundamental reassessment of assumptions in ecological and evolutionary analyses (Shefferson and Salguero-Gómez, 2015). For example, phylogenetic analysis assumes that macroevolution is a fundamentally slow process that does not feed back onto ecological systems except at long timescales. But, as we now know, this may not be fair. How do overlapping timescales affect our understanding of macroevolution (Shefferson and Salguero-Gómez, 2015)?

The roots of eco-evolutionary dynamics are diverse, and rather than present a list of names and their contributions, I will direct the reader both to the editorial for this special feature (Shefferson and Salguero-Gómez, 2015), which includes a short history of the field, and a few other important papers with some of the history detailed (Reznick, 2013, Pelletier et al., 2009, Hairston Jr. et al., 2005). However, I do wish to use this opportunity to present the contributions to the field of an evolutionary biologist who has exerted a major influence without necessarily being recognized for his importance. That individual is John B. S. Haldane, who is quoted at the beginning of the editorial.

Haldane was most certainly an important evolutionary biologist, known most for his contributions to the Darwinian Synthesis. He is also rather well-known for his staunch support of socialism and communism, his naturalization to India, and his criticism of the influence of money in science. However, among his most interesting writings are those that relate to the speed of evolution. Haldane often thought about how quickly natural selection can act, and suggested that rapid evolution might be quite rare. There were several reasons for this statement, most famously those dealing with the since resolved “Haldane’s dilemma”, which suggested that multiple traits in the same organism were not likely to evolve quickly via natural or even artificial selection because of the requirement of strong, consistent genetic correlations among those traits, combined with potentially harsh selection that would dramatically reduce the overall population growth rate (Haldane, 1957). Theoretical writings such as this and others by Haldane inspired some great research on the speed of evolution, and influenced even conservation via the concept of evolutionary rescue (Haldane, 1939, Carlson et al., 2014). These ideas are very important today, particularly when considered in light of the potential for evolution to interact with ecological processes via eco-evolutionary feedback (Yoshida et al., 2003).

My hope in co-editing this Special Feature is that other evolutionary ecologists will develop new theoretical and empirical systems in order to re-develop the field of evolutionary ecology with the new understanding of the overlapping timescales of ecology and evolution. This is very necessary, particularly because the dilemma facing evolutionary ecologists is not whether or not natural selection can act quickly, as it was in Haldane’s day, but rather that we know that it can and often does act quickly, yet do not understand the resulting consequences.

Rich Shefferson
Special Feature Guest Editor
Associate Editor – Journal of Ecology


Carlson, S. M., Cunningham, C. J. & Westley, P. A. H. (2014) Evolutionary rescue in a changing world. Trends in Ecology & Evolution, 29, 521-530.

Hairston Jr., N. G., Ellner, S. P., Geber, M. A., Yoshida, T. & Fox, J. A. (2005) Rapid evolution and the convergence of ecological and evolutionary time. Ecology Letters, 8, 1114-1127.

Haldane, J. B. S. (1939) The effect of variation of fitness. The American Naturalist, 71, 337-349.

Haldane, J. B. S. (1957) The cost of natural selection. Journal of Genetics, 55, 511-524.

Lamit, L. J., Busby, P. E., Lau, M. K., Compson, Z. G., Wojtowicz, T., Keith, A. R., Zinkgraf, M. S., Schweitzer, J. A., Shuster, S. M., Gehring, C. A. & Whitham, T. G. (2015) Tree genotype mediates covariance among diverse communities from microbes to arthropods. Journal of Ecology, 103, 840-850.

Metcalf, C. J. E., Burqhardt, L. & Koons, D. N. (2015) Avoiding the crowds: the evolution of plastic responses to seasonal cues in a density dependent world. Journal of Ecology, 103, 819-828.

Pelletier, F., Garant, D. & Hendry, A. P. (2009) Eco-evolutionary dynamics. Philosophical Transactions of the Royal Society B: Biological Sciences, 364, 1483-1489.

Reznick, D. N. (2013) A critical look at reciprocity in ecology and evolution: introduction to the symposium. The American Naturalist, 181, S1-S8.

Shaw, R. G., Wagenius, S. & Geyer, C. j. (2015) The susceptibility of Echinacea angustifolia to a specialist aphid: eco-evolutionary perspective on genotypic variation and demographic consequences. Journal of Ecology, 103, 809-818.

Shefferson, R. P. & Salguero-Gómez, R. (2015) Eco-evolutionary dynamics in plants: interactive processes at overlapping timescales and their implications. Journal of Ecology, 103, 789-797.

Utsumi, S. (2015) Feeding evolution of a herbivore influences an arthropod community through plants: implications for plant-mediated eco-evolutionary feedback loop. Journal of Ecology, 103, 829-839.

Williams, J. L., Jacquemyn, H., Ochocki, B. M., Brys, R. & Miller, T. E. X. (2015) Life history evolution under climate change and its influence on the population dynamics of a long-lived plant. Journal of Ecology, 103, 798-808.

Yoshida, T., Jones, L. E., Ellner, S. E., Fussmann, G. F. & Hairston Jr., N. G. (2003) Rapid evolution drives ecological dynamics in a predator-prey system. Nature, 424, 303-306.

ESA’s Centennial: A Swarm of Ecologists

I don’t know what the collective term is for a lot of ecologists gathered together at one time, but given my past experience with ESA Annual Meetings, a swarm seems to be an appropriate word. I’ll be attending this year’s Centennial Meeting of the Ecological Society of America in Baltimore and fully expect to be amidst a frenetic crowd of like-minded ecologists for a week. With all of the talks, symposia, posters, and other events, it should be an invigorating experience.

I know that I’ll be spoilt for choice in trying to decide which talk or session to attend – someone tweeted recently that there are 4,000 talks over the course of the meeting. This cornucopia usually results in coffee-fueled indecision leaving me twisting in the wind as I dash around looking for a room buried in the recesses of the convention center. Nevertheless, looking through the program, the following have caught my eye: 1) All three Centennial lectures are must-see events as they collectively touch on some of the most important ecological issues of the day; climate change, land fragmentation, and emerging diseases. 2) The Opening Plenary ‘Ecology’s Relevance to Earth’s Future’ will discuss the role of ecologists as planetary stewards. I expect that listening to these talks will cause me to reflect on what can I do to help planet Earth beyond research and teaching (I volunteer for a local non-profit land preservation group called Green Earth, Inc.). 3) Symposia: a couple of these are particularly relevant to research in my lab, i.e., Tuesday afternoon Symposium 7 ‘Beyond Invasional Meltdown: Implications and Impacts of Co-Occurring Invasive Species and Assessing Future Research Needs’, and Thursday morning Symposium 16 ‘100 Years of Agroecology: Pushing the Frontiers of Ecology’. 4) Organized Oral Sessions (OOS), Contributed Talks (COS) and Posters are the meat and potatoes of the meeting, and honestly, I tend to make last minute decisions on these and cruise the posters. One OOS that did catch my eye is OOS 8 Functional, Phylogenetic and Genetic Dimensions of Forest Diversity and Change’ on Tuesday afternoon. Of course, my own Tuesday morning 8:30 am talk in COS 25-2 Competition, ‘Detecting Early Onset of Intraspecific Competition through Root Visualization’ is not to be missed for those of you able to get up in time!

The British Ecological Society and the Journal of Ecology will be well represented at the ESA meeting with 15-20 Associate Editor board members in attendance, along with Bill Sutherland BES President (@Bill_Sutherland), Catherine Hill BES Head of Publishing (@CathJHill), and Hazel Norman BES Executive Director (@HazelNorman). Please feel free to track us down on the BES stand in the convention hall, or elsewhere, and ask us questions about publications, journals, or the Society. Ask me about the Associate Editor Blog Editor vacancy that we have (see previous blog post). If you can’t find me in the convention center, then I’m probably in a local coffee shop or one of Baltimore’s fine seafood restaurants. I’ll be live-tweeting on @DavidJohnGibson using #ESA100.

Associate Editor Vacancy – Journal of Ecology Blog (UPDATED)

Journal of Ecology is looking for an Associate Editor to join the Editorial team in order to run the Journal of Ecology blog. The blog was launched in 2012 and is intended to showcase Journal content in a more accessible format. It also serves as a platform for discussing topics that are of more general interest to the Journal’s readership and ecologists in general. The Blog Editor will be responsible for commissioning content for the Journal of Ecology blog and work closely with the Journal’s editorial team and editorial office to determine content. The Blog Editor will be expected to record, edit, and publish one podcast and approximately 2-3 blog posts per month. This content can be associated with content published in the Journal or it could be about more general topics of interest to the Journal’s readership. Please be aware that all final Editorial decisions will rest with the Journal’s Senior Editors. We are searching for an early career researcher is passionate about communicating plant ecology online, especially via social mediaDemonstrable previous experience would be of advantage. The role is for a(n) (initial) term of 1 year/ 2 years and unpaid, although benefits for the Journal’s Associate Editors will also be extended to this role. For more information and to express your interest please contact the Journal’s Assistant Editor, Lauren Sandhu, In your email, please include a CV with two academic references and detail briefly why you are interested, relevant experience you may have to date and your ideas for developing the blog.

UPDATE:  Closing date is Monday 14 September 2015

Editor’s Choice 103:4

Plant invaders: same difference?

To paraphrase Tolstoy, is each plant invader alike, or is each invasive in its own way? Among the hundreds of papers on this subject that have been published in the last two decades, a paper by Bezeng and colleagues stands out as an unusually thorough investigation in a flora of great interest to invasive species biologists and plant ecologists in particular: southern Africa. The paper, Revisiting Darwin’s naturalization conundrum: explaining invasion success of non-native trees and shrubs in southern Africa, by Bezeng, Davies, Yessoufou, Maurin, and Van der Bank, is the Editor’s Choice for the next issue of Journal of Ecology.

Predicting which introduced species become invasive, and which don’t, is one of the prime objectives of invasion biologists, but successes have been few. Some might point out that invasive species risk assessments often have high predictive ability—a model for U.S. Great Lakes fish introductions was especially good (Kolar & Lodge 2002)—but, particularly for plant introductions, the models overly rely on the trait of ‘is the species invasive elsewhere?’, which tells us little about the ‘how’ of invasions. Although use of plant traits to statistically separate invaders from non-invaders remains a cottage industry, there exist only a handful of traits available for most species, so ecologists are increasingly looking to other types of data for inferences about what, if anything, makes invaders special. Chief among these are genetic data that allow an examination of relatedness between native species and potential invaders.

Even before the invention of modern genetics, the relatedness of invasive and non-invasive species to natives was suggested as ‘risk assessment’ tool of sorts, and by none other than Charles Darwin. Darwin made the original argument for the association of niches and common descent that we now call phylogenetic signal (Losos 2008): all else equal, 1) more closely related species should be more ecologically similar, and 2) consequently, compete more intensely than less related species. Both of these claims are today hotly contested, and as data have accumulated Darwin’s Naturalization Hypothesis has given way to ‘Darwin’s conundrum’ (Diez et al. 2008), with no emergence of general patterns of native-invader relatedness or consensus about what exactly such patterns mean with respect to competition.

Bezeng et al. don’t solve the issue of whether genetic similarity maps neatly on to ecological similarity, but they do conduct one of the largest phylogenetic analyses of native-invader contrasts to date, using a complete two-locus phylogeny across 1400 woody southern African species. Results were clear: introduced woody species that have become invasive are, on average, less related to native woodies than those that haven’t. And in an interesting twist, simple traits like maximum height, seed mass, and flowering and dispersal characteristics that have shown to be invasiveness predictors in other studies did not separate invaders from non-invaders, although some traits were significantly different for non-natives compared to natives. This supports the idea that traits promoting initial establishment are different than those that promote competitive superiority and rapid spread (Richardson & Pyšek 2012), and further suggests that successful ecological strategies of invaders needn’t be reflected in simple traits, but rather be multidimensional—and, unfortunately, difficult to quantify.

Is there hope for a general theory of species invasiveness? Studies like Bezeng et al.’s suggest there is much to be gained from large floristic contrasts of native and introduced species. But ultimately, costly, multi-faceted studies of phenotype are required to make real progress on invasion mechanisms. In the context of invasions between populations of Homo sapiens, Tolstoy wrote that we can only know that we know nothing. In the case of biological invasions, we at least know that tools like phylogenetics tell us something—but what?

Jason Fridley
Associate Editor, Journal of Ecology


Diez, J. M., Sullivan, J. J., Hulme, P. E., Edwards, G., & Duncan, R. P. 2008. Darwin’s naturalization conundrum: dissecting taxonomic patterns of species invasions. Ecology Letters, 11: 674-681.

Kolar, C. S., & Lodge, D. M. 2002. Ecological predictions and risk assessment for alien fishes in North America. Science 298: 1233-1236.

Losos, J. B. 2008. Phylogenetic niche conservatism, phylogenetic signal and the relationship between phylogenetic relatedness and ecological similarity among species. Ecology Letters 11: 995-1003.

Richardson, D. M. & Pyšek, P. 2012. Naturalization of introduced plants: ecological drivers of biogeographical patterns. New Phytologist 196: 383-396.

We love plants! Happy International Fascination of Plants Day

Happy International Fascination of Plants Day from Journal of Ecology! In celebration Executive Editor, David Gibson, has interviewed Anthony Davy about the Journal’s Biological Flora of the British Isles series.

Editor’s Choice 103:3

Issue 103:3 is online now. The latest Editor’s Choice paper is “A spatially explicit model for flowering time in bamboos: long rhizomes drive the evolution of delayed flowering” by Tachiki et al. Associate Editor – Richard Shefferson – has written a commentary on the paper below.

Bamboos, sex, and the ultimate sacrifice

Nature is a randy thing. The Tree of Life has managed to produce life histories and reproductive modes so diverse that biologists studying reproductive evolution keep finding new surprises all the time. Human reproduction, with its long delay until reproductive maturity, and economic and emotional considerations determining timing, is remarkably boring in relation to the diversity of sex in nature. The commonness of homosexual behavior (Sommer and Vassey 2006), group sex, sexual cannibalism, and even the mass dumping of gametes into the environment as occurs in many marine organisms and wind-dispersed trees, boggles even the most prurient mind.

Enter the monocarpic perennial. These are plants that commonly live more than one year, and so are perennial, but only reproduce once. Following reproduction, they die, and indeed they typically use up all available resources in reproducing, which results in death. Certainly, this mode of reproduction makes these plants sound as though they belong to a cult, long since gone extinct through its misguided puritanism. However, these plants include a diversity of forms and species throughout the plant kingdom, from the famed century plant and other agaves, which can live for many decades before reproducing and dying, to some legumes and many species of bamboo, which typically live for a number of years before reproducing and dying en masse.

Typical pachymorph (left) and leptomorph (right) type bamboos (photo credit: (left) Akifumi Makita, (right) Yoshihisa Suyama)

Typical pachymorph (left) and leptomorph (right) type bamboos (photo credit: (left) Akifumi Makita, (right) Yoshihisa Suyama)

But why should any organism have such a bizarre life history strategy? Much of what we know about the evolution of reproductive timing comes from work inspired by Lamont Cole’s citation classic on life history evolution (Cole, 1954). That monograph attempted to explain the evolution of “annual” and “perennial” reproductive modes via a simple evolutionary model, and instead led to the realization that the increased fitness from a perennial strategy was so slight as to be negligible. Since that time, we have come to understand that all sorts of factors can influence reproductive timing, the optimal number of reproductive events, and all aspects of life history. However, models that could account for the observed reproductive timings of long-lived monocarpic perennials such as the century plant remained elusive until the marriage of game theory and demographic modeling, and in particular the development of integral project models (Childs 2003, Rees et al 1999, Rees & Rose 2002)

An inflorescence of dwarf bamboo, Sasa veitchii var. hirsuta (photo credit: Ayumi Matsuo)

An inflorescence of dwarf bamboo, Sasa veitchii var. hirsuta (photo credit: Ayumi Matsuo)

And this is where this issue’s highlighted paper comes in. Bamboos are truly bizarre species, and include a good number of plant species that reproduce both clonally and sexually. In some species, the combination of reproductive modes yields stands of tall, tree-like bamboos that form veritable forests of genetically different individuals. These individuals are actually all the same age, but cover different areas due to the combination of where their seeds germinated and the growth and spread of their rhizomes. And then, at some point, the entire stand produces flowers, reproduces sexually, and dies. As if this mode of synchronous sexual reproduction wasn’t interesting enough, bamboos actually exhibit a latitudinal cline in flowering intervals, with short intervals in tropical areas and increasingly large intervals moving northward into temperate areas.

Simultaneous withering after flowring of Sasa veitchii var. hirsuta (photo credit: Yoshihisa Suyama)

Simultaneous withering after flowring of Sasa veitchii var. hirsuta (photo credit: Yoshihisa Suyama)

Previous ideas about why bamboo reproduction is so odd include herbivore satiation (Janzen 1976), which is a hypothesis used explain masting behavior (synchronous reproduction over large areas), and well as evolution in response to fire intervals (Keeley and Bond 1999). However, models that explain observed flowering intervals have remained elusive. To tackle this problem, Tachiki et al. (2015) created a spatially explicit model to explore the evolution of flowering interval as a function of rhizome growth and seed dispersal distance. They found, among other interesting results, that increasing rhizome growth leads to delayed flowering time, while increasing seed dispersal distance does the opposite. These particular strategies seem to work evolutionarily because of their impacts on patterns of competition. For example, when seeds disperse near the mother plant, kin competition is intensified and sexual reproduction becomes less successful. This yields an advantage to plants that reproduce more clonally, and so favors a longer reproductive interval. Fascinatingly, their model actually seems to account for the noted geographic pattern in flowering interval. This work suggests that the population dynamics of the plant may actually strongly drive these patterns, in contrast to previous hypotheses involving herbivory and environmental stressors.

As someone who studies the life histories of long-lived plants fairly regularly, I must say that it was a pleasure to be a part of the process bringing this paper to the readership of Journal of Ecology. Hopefully it might inspire more interesting work on the subject, and perhaps even inspire more of our young BES members to work in East Asia, a geographic region with a great deal of unexplained biodiversity, and untapped research talent.

Richard Shefferson

Associate Editor, Journal of Ecology


Childs D.Z., Rees M., Rose K.E., Grubb P.J. & Ellner S.P. (2003). Evolution of complex flowering strategies: an age- and size- structured integral projection model. Proceedings of the Royal Society of London Series B-Biological Sciences, 270, 1829-1838.Cole, L. C. (1954) The population consequences of life history phenomena. Quarterly Review of Biology, 29, 103-137.
Janzen, D. H. (1976) Why Bamboos Wait So Long to Flower. Annual Review of Ecology and Systematics, 7, 347-391.
Keeley, J. E. & Bond, W. J. (1999) Mast flowering and semelparity in bamboos: the bamboo fire cycle hypothesis. American Naturalist, 154, 383-391.
Metcalf, C. J. E., Rose, K. E., Childs, D. Z., Sheppard, A. W., Grubb, P. J. & Rees, M. (2008) Evolution of flowering decisions in a stochastic, density-dependent environment. Proceedings of the National Academy of Sciences, 105, 10466-10470.
Metcalf, J. C., Rose, K. E. & Rees, M. (2003) Evolutionary demography of monocarpic perennials. Trends in Ecology and Evolution, 18, 471-480.
Rees M., Childs D.Z., Metcalf J.C., Rose K.E., Sheppard A.W. & Grubb P.J. (2006). Seed dormancy and delayed flowering in monocarpic plants: Selective interactions in a stochastic environment. Am Nat, 168, E53-E71.
Sommer, V. & Vasey, P. L. (2006) Homosexual behaviour in animals: an evolutionary perspective. Cambridge University Press, Cambridge, United Kingdom.
Tachiki, Y., Makita, A., Suyama, Y. & Satake, A. (2015) A spatially explicit model for flowering time in bamboos: long rhizomes drive the evolution of delayed flowering. Journal of Ecology, 103, 585–593.

Demography to infinity and beyond!

One of my favourite manuscripts provides a detailed account as to why evolutionary biologists should be demographers (Metcalf & Pavard 2007). The authors argue that, because the propagation of genes into future generations depends on the st/age-specific vital rates of survival, fecundity and migration of individuals within and between populations, and such rates are precisely at the core business of demography, a formal link exists between both disciplines… but that this link has not been explored to its full potential. Based on the strong belief that the ramifications of demography are indeed much broader than “just” the population, and that they reach out to evolutionary biology, and also to genetics, physiology, conservation biology, and community and landscape ecology, we (below) organised the symposium “Demography beyond the Population”, which took place two weeks ago (March 24-26 2015) in Sheffield, UK. This symposium was supported by the British Ecological Society, and brought together ca. 100 delegates from all four corners of the world (e.g. UK, USA, Russia, French Guiana, Brazil, Australia, Mexico).

BES merchandise

In case you were not able come to Sheffield or follow us on Twitter (Alden Griffith (@alden_griffith) and myself (@DRobcito) tweeted frequently using #BeyondDemog), allow me to virtually walk you through some of the highlights of the symposium. This demographic extravaganza actually started on Monday March 23rd with five workshops on integral projection models (Metcalf et al. 2013, Merow et al. 2014), age-by-stage matrix population model decompositions (Caswell 2012; Caswell & Salguero-Gomez 2013), continuous physiological models (de Roos 2008) and Bayesian survival analyses (Colchero et al. 2012). These four workshops showcased the vast richness of analytical approaches to analyze individual-level demographic records, even in the presence of uncertainty (BaSTA). To me, however, the greatest highlight of that day was a mini-workshop ran over lunch by Marco Visser on the importance of programming efficiently for demographic analyses. Marco and his colleagues recently published a manuscript with great tips for ecologists and evolutionary biologists (Visser et al. 2015), resulting from a working group organized at the Max Planck Institute for Demographic Research in 2012. Marco’s presentation, based on this publication, emphasized the need to think very carefully how to expedite calculations: when should you get a more powerful computer?, when to bother with parallel core processing?, or simply how does one track which lines of code are taking most RAM (and how to make them faster)? I have learned a lot from the useful advice from Marco, and I have already started to apply it to my own programming. Certainly Marco is an early career ecologist to keep in the radar due to his already important scientific and computational contributions to the field (

The official start day of the symposium, Tuesday, and the rest of it, took place at Cutler’s Hall. To say that I’ve never been to a conference venue like would be quite an understatement… I’ve never been to a wedding venue like this one either! Great corridors, a broad, red-carpeted stair with a large painting of the queen welcoming us at the end, and then the English grandeur of the conference room.

Cutlers Hall

The symposium covered a wide range of topics at the forefront of demography and its application. The invited speakers included Yvonne Buckley, Johan Ehrlén, Hal Caswell, Steve Ellner, Elizabeth Crone, Jordan Golubov, Dave Hodgson, Eelke Jongejans, Frank Schurr, Maria del Carmen Mandujano, Shripad Tuljapurkar, Mark Rees and María Uriarte. Collectively, they highlighted the importance of including major axes of variation in demography (variation through space, through ecological time, through evolutionary time, and through disciplines) to better understand the context in which demographic processes operate and how far one can project in time before projections become too uncertain. I was particularly excited to see Elizabeth Crone’s presentation about how to model the variation in vital rates as a function of time, space and plant’s “personalities”. The latter, personalities, is a term commonly used in human demography (Chen et al. 2006) whose analyses are finally making their way into non-human ecology and evolution. Maria del Carmen Mandujano & Jordan Golubov gave a combo-presentation drawing from phylogenetic analyses and demographic field data in the Cactaceae to evaluate the role of seedbanks (one of the big unknowns in plant demography), and a novel approach to incorporate genetic structure into matrix population models in an Opuntia species.

One of the main premises in demography is that individuals contribute to the population differently as a function of their age, stage or size. Honouring this fundament of demography, and having admittedly only briefly covered above some contributions by more senior scientist contributed to the symposium, I have the full intent to focus what follows in early career folks exclusively. Demography has in the last years experienced a rather prominent recruitment event (yep, pun intended!), whereby a sizable number of early career ecologists and evolutionary biologists are making very important, dynamic contributions. As a result of their oral presentations and accompanied posters, three students were recognized with awards sponsored by Journal of Ecology and the British Ecological Society. The two runner-ups were Julia Barthold and Maria Paniw. Julia and Maria presented respective state-of-the-art research lines on the estimation of unobserved demographic processes such as mortality rates in migrant male lions (Barthold), and seedbank rates of another carnivorous (plant) creature: Drosophylum lusitanicum (Paniw). The winner of the student award was Edgar Gonzalez, based on his work on the “inverse demographic problem”. This challenge consists on the determination of individual-level vital rates based on the observation of population structures, and it is one of the long-standing unresolved questions in our field. Interestingly, and perhaps not by coincidence, Edgar, Julia and Maria’s approaches were based on Bayesian statistics, further supporting my thought that we will all soon be talking priors and posteriors. If you haven’t taking at least an intro course in Bayesian statistics… you might soon become rusty in population studies!

Other very interesting presentations included the decomposition of individual heterogeneity effects onto whole-population dynamics by Merel Jansen, based on a publication in Journal of Ecology (Jansen et al. 2012), bee demography using integral projection models (IPMs) by Natalie Kerr, the examination of which climate variables affect most the demography of a rare orchid also using IPMs by Sascha van der Meer, or the decomposition of plant-animal interactions on a plant population using (you guessed it!) IPMs by Zdenek Janovsky. Matrix Population Models (MPMs; Caswell 2001) and IPMs (Easterling et al. 2000, Metcalf et al. 2013, Merow et al. 2014) were indeed a recurrent tool throughout the symposium, as it was the recently launched COMPADRE Plant Matrix Database , published this year in Journal of Ecology (Salguero-Gómez et al. 2015), and used by Dave Hodgson, Shaun Coutts, Anna Csergo, Yvonne Buckley and myself on separate talks to explore questions as broad as the structuring factors of transient dynamics, the role of phylogenies and geographic proximity on population dynamics, or the connection between traits and life history strategies.

An important advancement in the field of plant population ecology is underway. I already commented in an earlier blog on the need to replicate plots through space more extensively to really encompass the range of demographic responses and underlying mechanisms that (plant) species may display. Suzzane Lommen has been conducting a European-wide project in the last years coordinating data collection of the invasive ragweed by researchers. Maria Begoña García shared with us her valuable experiences in organizing and engaging with the general public to collect demographic information on various endangered plant species in NE Spain. Last by not least, Yvonne Buckley ran a break-out group discussion on the recently launched PlantPopNet, a globally replicated demographic census of the cosmopolitan Plantago lanceolata with the ultimate goals of trying to understand the local, regional and global determinants of population dynamics in the wild (

But of course most science developed not in the main hall, but away from oral presentations. We, the organizers, made sure to have ample and frequent coffee breaks and to work with our local co-organizer, Dylan Childs, to give the symposium participants a true Sheffield experience. Furthermore, some social events were planned throughout the symposium, which included an informal networking event at a local pub sponsored by the BES journals and a brewery tour on the Wednesday night. I have since heard great things about the tour of the brewery!

The Fat Cat

Ultimately, I hope that this symposium will have been thought-provoking to all its participants and that we will all go back to our home institutions with a better understanding of what the big questions are, and what directions we should push next to take “demography beyond the population”. And now that we have almost recovered from this symposium, all co-organizers are working with five BES journals (Journal of Ecology, Journal of Animal Ecology, Journal of Functional Ecology, Journal of Applied Ecology and Methods in Ecology & Evolution) to put together the first-ever cross-BES-journals special feature… stay tuned!

I must also express my greatest gratitude to Lauren Sandhu, Andrea Baier, Amelia Simpson, Amy Everard, Richard English and the rest of the fantastic BES staff team for the excellent support prior to and during the symposium. It has been a pleasure working with the BES. I can’t wait for the 13-16 December BES annual meeting!

Rob Salguero-Gómez

Associate Editor, Journal of Ecology

Information about the symposium organizers:

Here is a picture that Amelia took of all the symposium organizers at the end of the symposium.

Organisers 2

Rob Salguero-Gómez (Associate Editor Journal of Ecology)
The University of Queensland (Australia)
Max Planck Institute for Demographic Research (Germany)
Cory Merow
Fish & Wildlife Service (USA)
University of Connecticut (USA)
Alden Griffith
Wellesley College (USA)
Dylan Childs (AE Journal of Animal Ecology)
Sheffield University (UK)
Jess Metcalf (AE Methods in Ecology & Evolution)
Princeton University (USA)
Sean McMahon (AE Methods in Ecology & Evolution)
Smithsonian Environmental Research Center (USA)


H Caswell (2012) Matrix models and sensitivity analysis of populations classified by age and stage: a vec-permutation matrix approach. Theoretical Ecology
5: 403–417.

H Caswell & R Salguero-Gómez (2013) Age, stage and senescence in plants. Journal of Ecology 101: 585-595.

Y-F Chen, C-M Wang & H-J Lin (2006) Explore the relationships among demography, personality traits and self-directed learning. The Journal of Human Resource and Adult Learning Nov: 141-150

F Colchero, OR Jones & M Rebke (2012) BaSTA: an R package for Bayesian estimation of age-specific survival from incomplete mark-recapture/recovery data with covariates. Methods in Ecology and Evolution 3: 466–470.

MR Easterling, SP Ellner & PM Dixon (2000) Size-specific sensitivity: applying a new structured population model. Ecology 81: 694-708.

M Jansen, PA Zuidema, NPR Anten & M Martinez-Ramos (2012) Strong persistent growth differences govern individual performance and population dynamcis in a tropical forest understory palm. Journal of Ecology 100: 1224-1232

C. Merow, JP Dahlgren, CJE Metcalf, DZ Childs, MEK Evans, E Jongejans, S Record, M Rees, R Salguero-Gómez, SM McMahon (2014) Advancing population ecology with integral projection models: a practical guide. Methods in Ecology and Evolution 5: 99-110.

CJE Metcalf & S Pavard (2007) Why evolutionary biologists should be demographers. TRENDS in Ecology and Evolution

CJE Metcalf, SM McMahon, R Salguero-Gómez & E Jongejans (2013) IPMpack: an R package for integral projection models. Methods in Ecology and Evolution 4: 195-200.

AM de Roos (2008) Demographic analysis of continuous-time life-history models. Ecology Letters 11: 1-15.

R Salguero-Gómez, OR Jones, CR Archer, YM Buckley YM, J Che-Castaldo, H Caswell, A Scheuerlein, DA Conde, A Baudisch, E Brinks, H de Buhr, C Farack, F Gottschalk, A Hartmann, A Henning, G Hoppe, G Römer, J Runge, T Ruoff, J Wille, S Zeh, D Vieregg, R Altwegg, F Colchero, M Dong, D Hodgson, H de Kroon, J-D Lebreton, CJE Metcalf, M Neel, I Parker, T Takad, T Valverde, LA Vélez-Espino, GM Wardle, M Franco & JW Vaupel (2015) The COMPADRE Plant Matrix Database: an online repository for plant population dynamics. Journal of Ecology 103: 202-218.

MD Visser, SM McMahon, C Merow, PM Dixon, S Record & E Jongejans (2015) Speeding up ecological and evolutionary computations in R; Essentials of high performance computing for biologists. PLOS Computational Biology DOI:10.1371/journal.pcbi.1004140