Musings, Explorations, and Announcements

At DRUG today, Chris Hamm (email) showed us an easier way to combine multiple figures into one plot using plot.new, rather than par(mfrow=...) Here’s his script: .knitr.inline { background-color: #f7f7f7; border:solid 1px #B0B0B0; } .error { font-weight: bold; color: #FF0000; }, .warning { font-weight: bold; } .message { font-style: italic; } .source, .output, .warning, .error, .message { padding: 0em 1em; border:solid 1px #F7F7F7; } .source { background-color: #f7f7f7; } .

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Pretty raw notes this week from a discussion about how food webs respond to nutrient starvation and excess. Whalen on consumption in Food Webs Boersma and Elser (2006) - fitness cost of excessive P. Implications for models - but what about competition as a more likely limiting factor? Not sure about the “food left on the table” argument. What about the metabolic costs? Not mentioned in the paper. Nonlinearity in P-growth relationship could be coexistence mechanism Raubenheimer and Simpson (2004) - Fitness and body composition can be affected by food quality.

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In D-RUG today, Stella Copeland gave a quick introduction to mixed models in R. Here’s the script that she presented:

Get the data file for this script here

Stella also recommends this paper by Ben Bolker as a quick introduction to the topic.

The Davis Chapter of the Society for Conservation Biology sent along this great voter guide for upcoming California propositions: SCB voter’s guide Nov 2012 ballot measures relevant to conservation Prop 37 Mandates labeling of genetically modified food. Prohibits such food from being labelled as “natural”. However, this law would exempt foods that are certified organic, foods unintentionally produced with genetically modified material, meat of animals fed genetically modified food but that are not genetically modified themselves, alcoholic beverages, and food sold in restaurants.

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Our ecological stoichiometry course kicked off today. My initial training is in this area, which I called “ecosystem biogeochemistry”, but it was very much a geologically focused, big systems approach. It’s interesting to approach this material from a more organism- and population-centric perspective that most Davis ecologists have. Today, Alison started us off with some first principles of nutrient constraints on ecology. Drawing a lot from Sterner and Elser (2002), but noting that a lot of these principles go all the way back to Lotka (1925).

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