I’ve updated our dataset on fruit colors that we used in the Journal of Evolutionary Biology paper. The full metadata is here, in the Dryad open-source repository. You can find this and other datasets also in the web page.
pedroj (Pedro Jordano) · GitHub. I’m using github to keep collections of my code as a repository. Instead of using their repo service, I’m using the gists, uploading chunks of R (also MATLAB/Octave) code I’m working with. A gist is just a chunk of code you are working with and might be useful to someone else…
Yes, we sent the book manuscript to Princeton University Press last week. It has been an intensive work during the last four years but I’ve really enjoyed this adventure. I’ve been delighted with the creative work with the figures (around 60), and the challenges of seeting all them in grayscale, which I think is very elegant. We are still waiting for the reviewers’ comments; I hope we succeeded in presenting a simple, yet reasonably complete overview of mutualistic interactions. I’ll keep posting news about how the production stages advance!
The University of Sevilla has awarded Francisco Rodríguez with the PhD Excellence Award, 2012. Paco carried out his PhD project in the lab, working on dispersal ecology of Laurus nobilis. Big congratulations Paco!!!
I’m about to complete the moving of my blog (started by early 2003…) to WordPress. There are several reasons for this- the most important being the ability to edit from the tablet and phone, and better versatility with the editing and composition of entries. I keep using iWeb and Dreamweaver for the web page, however, at least until iWeb is discontinued by Apple. The older version of the blog is here. The new blog in WP is called “The Red Notebook“.
I’m just arrived from the field course in Brazil. Everything run very well and we really enjoyed this edition. Here is a photo of Aburria jacutinga in a Cecropia glazouvi tree. I’ve uploaded more photos in my FB portal.
I’m in the process of moving photo repositories to iCloud and have my previous photos of megafauna fruits and seeds moved to this gallery. You can access the photos here.
These photos were taken in the herbarium of Museu Goeldi (Belém, Pará, Brazil) in 2002. They include many of the species we discuss in our paper in PLoS One on megafauna fruits.
Editor’s Choice section of Science (vol. 333: 1201) this week includes a comment by Andrew Sudgen on our recent paper just published in Ecology Letters. The comment highlights the innovative aspects of studying multispecific coevolution and developing the first model to address the consequences of diversified interactions within complex mutualistic networks.
Just appeared in the Sept issue of Ecol. Lett. A major current challenge in evolutionary biology is to understand how networks of interacting species shape the coevolutionary process. We combined a model for trait evolution with data for twenty plant-animal assemblages to explore coevolution in mutualistic networks. The results revealed three fundamental aspects of coevolution in species-rich mutualisms. First, coevolution shapes species traits throughout mutualistic networks by speeding up the overall rate of evolution. Second, coevolution results in higher trait complementarity in interacting partners and trait convergence in species in the same trophic level. Third, convergence is higher in the presence of super-generalists, which are species that interact with multiple groups of species. We predict that worldwide shifts in the occurrence of super-generalists will alter how coevolution shapes webs of interacting species. Introduced species such as honeybees will favour trait convergence in invaded communities, whereas the loss of large frugivores will lead to increased trait dissimilarity in tropical ecosystems.
This is a first attempt to get to models of how coevolved changes might drive the evolution of highly diversified networks of ecological interactions. Each of the interactions that we can map in these networks really represents a set of reciprocal selection forces deriving from the interaction itself. Up to know we were lacking a general theory of how coevolution can proceed in these diversified assemblages, given that these natural selection forces remain diversified, asymmetric and, generally, weak. We show that strictly coevolved changes might in fact be scarce in this scenario, but they trigger cascades of changes that significantly contribute to the evolving network. The work stems on my ongoing collaboration with Paulo R. Guimarães and John N. Thompson, and the excellent work Paulo developed during his postdoc stay in Sta Cruz at John’s lab.
Seed dispersal by lizards is an insular phenomenon. In the Canary Islands, many fleshy-fruited plants depend on lizards for their successful dispersal and recruitment. We are now working in a project directed by Alfredo Valido to analyze the movement ecology of Canarian endemic Gallotia lizards and its consequences for plant dispersal and recruitment. We study the reproductive ecology of orijama plants Neochamaelea pulverulenta, an endemic Cneoraceae in the islands, whose seeds are exclusively dispersed by the lizards. We combine studies of fine- and medium-scale genetic structure with data and models of foraging movements of the lizards, monitoring with radio-tracking methods. So far the results are superb, and we now have detailed data on movement patterns of Gallotia galloti in Teno Bajo (Tenerife)- our main study site- and G. stehlini (in the photo) in Barranco de Veneguera (Gran Canaria). We have also seeds samples from two 1.2 ha plots in the two sites as well as leaf samples from >2000 plants to assess seed dispersal patterns with genetic methods, similar to those that we’ve been using with Prunus mahaleb and Frangula alnus. We are interested in assessing the potential effects of previous extinctions of other giant lizard species (e.g., G. goliath) that were very good dispersers of orijama. These were up to 1.3 m long and able to disperse even the largest fruits and seeds of orijama, which now remain undispersed on the plants; only the smaller fruits and seeds remain dispersed by the extant smaller lizards.
Our study on the evolution of visual displays in plants appeared in the last issue of JEB. We are still working on this subject, now exploring how effective are visual displays (fruit colors) in attracting avian frugivores that might use color cues to build up complex and diverse fruit diets. We have evidence that strongly frugivorous birds might use color cues to guide foraging for fruit combinations that maximize the yield of important nutrients. Rather than consuming fruits at random, frugivorous warblers are quite selective not only on the fruit species they take, but in which combinations they consume the different fruit species.
This is my note #1. Created 01/01/2011 @ 00:35. Really a few minutes after the Biodiversity year has ended. What do we have? Probably a few thousands more extinct species, many of them we yet don’t know. But we have also more knowledge to fight this fast-paced trend of biodiversity loss. Let’s hope the best…
I have imported my previous posts of my blog.
Fruits show an immense diversity of colors and displays. However, we are still far from a general theory for the evolution of fruit displays. The main elements of those displays do not only include color itself, but also characteristics of the fruit “design” (ow the fruit is built) like number of seeds, amount of pulp, size, etc., and the nutrients in the pulp (both macro- and micro-nutrients, as well as secondary compounds). All this adds an extraordinary complexity and diversity to the fruit displays. Together with Alfredo Valido and Martin Schaefer I’ve been exploring the evolutionary patterns of fruit traits for the Iberian Peninsula fleshy-fruited flora (ca. 120 species). We studied whether correlated trends between these elements of the display (design, nutrients, color) have been maintained through the phylogenetic diversification of the flora. We found some interesting patterns of covariation between sugar content, lipid content, and color that suggest predictable patterns of fruit evolution in relation to the main types of frugivores feeding on the fruits. Our results suggest that the evolution of fruit displays has been quite constrained by history, yet selection by frugivores might have contributed to marked and predictable covariation among color and nutrient contents. This is an interesting finding to understand the evolution of visual signals in plants, acting to attract diverse suites of animal frugivores that can act as legitimate dispersers of the seeds. Our work is now in press in Journal of Evolutionary Biology.
PhD thesis defense by Débora Rother: “ Débora defended her thesis at UNESP (Rio Claro, Brazil) the 30th Nov. The thesis is entitled: ‘Dispersão de sementes e processos de limitação demográfica de plantas em ambientes com e sem bambus na floresta pluvial Atlântica’. She addressed the patterns of regeneration in the Atlantic rainforest of SE Brazil by combining observational studies of seed rain and seedling emergence and experimental seed addition. She studied Euterpe edulis, Sloanea guianensis, and Virola bicuhyba. The dispersal patterns of these species and their regeneration are deeply influenced in this forest by the presence of bamboo (Guadua tagoara) stands. This heterogeneity causes variation in the composition of the frugivorous avifauna and the density of seeds and established seedlings. She addressed the specific demographic transitions from dispersed seed to established saplings that can limit the natural regeneration of these forests. Bamboo stands influenced seed rain patterns in the complex mosaics of Atlantic rainforest areas, with a variable importance across seasons on the abundance of recruits and species richness of the seed rain. Besides, the hotspots of recruitment were shown as extremely dynamic and related to the spread and decline of G. tagoara stands. Bamboos promote the forest heterogeneity, but the characteristics of rapid colonization of G. tagoara and its invasive behavior can be one additional factor for limiting the growth of plant community and thus its management is important.
The defense went very well and she has already in press or submitted manuscripts of several chapters. Congratulations Dé for an excellent work!”
(Via Weblog de Pedro.)
The long and short of it
Back from the very interesting workshop organized in Madrid by Juanjo Robledo-Arnuncio. We focussed on long-distance dispersal events (LDD) and their importance to understand the potential responses to climate change. Changes in the environment will force adaptations or long-distance migration and range expansion in plants. Thus a key question is, are the LDD services provided by animal frugivores potentially allowing this environmental tracking.
We have been advancing a lot in understanding the local, stand-level patterns of dispersal and their consequences. Yet there are numerous conceptual and methodological challenges to understand migration among patches or fragments. LDD events > 500 km will be extremely difficult to assess in a robust way with current techniques, given the tremendous logistic challenge of sampling all the potential available pollen and seed sources. However, LDD events @100 km scale are probably affordable to estimate with a combination of mechanistic models (i.e., relying on high-precision satellite tracking of animal movement combined with physiological models) and genetic tools. Large scale sequencing and cheaper DNA analysis will help to genotype massive amounts of samples and allow the identification of rare immigrants, even when migration rates are low. Some lasting conceptual challenges include the estimation of 2D dispersal kernels that accommodate the complex reality of natural landscapes and the complexities of animal movement, which is quite often markedly directional and anisotropous.
The program of this interesting and thought-provoking workshop is here:
Long distance dispersal (LDD): perspectives and new directions
December 2nd, 2010
Sala Javier Palacios
Centro de Investigación Forestal (CIFOR)
Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA)
Ctra. de la Coruña km 7,5
8h45 – 9h00. Introduction (Juanjo Robledo-Arnuncio)
9h00 – 10h00 Keynote Speaker: Prof. Ran Nathan (Univ. Jerusalem)
A movement ecology approach to study LDD of plants
10h00 – 10h50. Prof. Pedro Jordano (EBD-CSIC)
Frugivores, seeds and genes: tracking the LDD events and their consequences
10h50 – 11h20. Coffee break
11h20 – 12h10Dr. Frederic Bartumeus (CEAB-CSIC)
LDD: Seed curves, Skewness and Anomalous Diffusion
12h10 – 13h00. Prof. Miguel Ángel de Zavala (Univ. Alcalá)
Species distribution models and long-range dispersal
13h00 – 14h30. Lunch at INIA
14h30 – 15h20. Dr. Juanjo Robledo-Arnuncio (CIFOR-INIA)
Genetic estimation of LDD among plant populations
15h20 – 17h00. Open Discussion (+ coffee)
17h00. End of mini-symposium