Musings, Explorations, and Announcements

Jordi Bascompte gave a Storer Lecture at UC Davis on November 15, 2012. Here are my rough notes: Biodiversity as the set of interactions between species, rather than accounting of species Most research in mutualism in evolution focus on bilateral interactions (e.g., Darwin’s orchids and moths) Jordi’s goal is to use network theory to represent mutualism in ecological communities and generalize about them. Three Using data sets on man mutualistic communities (pollinators, frugivores),

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Lauren Yamane talked about Andersen et al. (2004) in our Ecological Stoichiometry course today. Here are her slides, and below, my rough notes on the paper: Notes on the Paper Stoichiometry is a way of representing food quality - there is evidence that consumers have preference for high quality (e.g., low C:N) food. There is often a mismatch between composition of prey (autotrophs) and needs of consumers. Autotrophs have variable C:N ratios, consumers are more constrained.

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Today at Davis R Users’ Group, Rosemary Hartman took us through her work in progress fitting general additive models to organism presence/absence data. Below is her presentation and script. You can get the original script and data here Also, check the comments below for some discussion of other options for this type of analysis, such as boosted regression trees. ## GAMs using mgcv and amphibian presence/absence dataset ## code and data by Rosemary Hartman (rosehartman at gmail dot com) ## First, load the mgcv package (Simon Wood) library(mgcv) ## Now, attach your data set (or my data set) fishlakes <-read.

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Tomorrow in my stoichiometry seminar I’ll be talking about the dynamics of growth under multiple nutrient limitation and acclimation. Here are my notes: Rastetter and Shaver (1992) In this paper, Rastetter and Shaver introduce a model of plant growth on multiple nutrients, with the goal of understanding the conditions under which single- and multiple-nutrient limitation arise, the difference between short- and long-term behavior, and the role of organism-environment feedbacks. It’s not entirely clear whether this is on the scale of a single or a population.

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Ryan Peek showed us how to use an .Rprofile file to customize your R setup. Here are his instructions and script: For Windows To change profile for R, go here: C:\Program Files\R\R-2.15.1\etc (or whatever version you are using) Edit the “Rprofile.site” file Restart R For Macs Create your Rprofile file. -use TextEdit or another editor to create a file called Rprofile.txt In a terminal window, type:

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