An unexpected herbivore

Columbines are toxic! Like larkspurs, columbines are supposedly toxic to most livestock and humans. So say the books. This rabbit doesn’t listen to the books. (The internet, in its infinite wisdom, says that the eastern species has edible – to human – flowers, so maybe the rabbit is just rather tech-savvy)

I actually suspect that the roots and leaves may be somewhat toxic but the reproductive parts, including the flowers and pedicels (which the same rabbit eats in the next video!), are not. Deer also eat them, especially in one particular population, which I’ve mostly stopped using for experiments because of it. Wild speculation aside, just thought I’d share the video as I got a kick out of it.

Also, a question – is this a brush rabbit (Sylvilagus bachmani), a European rabbit (Oryctolagus cuniculus) or a black-tailed jackrabbit (Lepus californicus)? . A terrible still of the tail from the video is below. I feel a bit silly that I can’t even conclusively get it to genus. I’d be kicking myself pretty seriously if I couldn’t get a dragonfly, bird, wildflowers, or butterfly to genus and really this should be far easier!


UC Davis at ESA 2016

UC Davis will make a strong showing for the 101st meeting of the Ecological Society of America in Ft. Lauderdale, FL this year! We have 30 students, postdocs, faculty, and recent graduates giving 1st author oral or poster presentations. Come see your talented colleagues showcase the variety of fascinating ecology research they’ve been up to recently. Click on any talk title below to go to the full abstract, time and location in the ESA program. The full program can be found here.

If you’re on twitter, be sure to follow the #ESA2016 hashtag (and the @davis_egsa account!) for a whole new way to experience conferences. We’ll also be sending out tweet reminders about these UC Davis affiliated talks and posters about an hour or two before they start.

Don’t forget to join us for the annual UC Davis Ecology mixer on Wednesday starting at 6:30 PM EDT. The venue is Grille 66 & Bar, which is about a half mile walk from the ESA conference venue. Details can be found on the Facebook event page. Hope to see you there!

Monday, August 8th

Name Title/Link
Meredith Cenzer Natural selection and maladaptive plasticity counteract each other on a native and invasive host plant in soapberry bugs
Toby Maxwell Soil properties drive carbon-water relations across a climate gradient in Sierra Nevada forests
Ash Zemenick A picture of nectar: Do pollinators and nectar robbers vector unique microbe communities to columbine (Aquilegia formosa) nectar?
Nick Rasmussen Determining the consequences of phenological shifts for plant-herbivore interactions: An experimental approach

Tuesday, August 9th

Name Title/Link
Noam Ross Joint circulation of viral diseases in a bat population
Lucas Silva The strength of weak ties: The influence of soil-plant interactions on ecosystem restoration trajectories
Daniel Karp Co-managing fresh produce for nature conservation and food safety in California’s Central Coast
Rebecca Hernandez Organic and inorganic soil carbon in global aridlands
Jordan Hollarsmith Short-term estuarine acidification: Spatially complex impacts of upwelling and run-off on oyster growth and water chemistry in a Northern California estuary
Meghan Skaer Thomason Hydrologic variation drives dynamics of invasive aquatic plant spread at three spatial scales in a managed river
Kara Moore Experimental ecology and evolution in the field: A unique course for upper-level undergraduates and instructors
Kate Tiedeman Experimental ecology and evolution in the field: A unique course for upper-level undergraduates and instructors

Wednesday, August 10th

Name Title/Link
Alan Hastings Challenges in applying tipping point concepts to social-ecological systems
Julea Shaw Patch size effect on a native plant community within a grassland restoration setting
David Spiller Predators suppress herbivore outbreaks and enhance plant recovery following hurricanes
Swati Patel The stabilizing and destabilizing effects of eco-evolutionary feedbacks
Grace Charles Impacts of different large herbivores on ecosystem function: Cattle increase mean productivity, and wild herbivores reduce variability around the mean

Thursday, August 11th

Name Title/Link
Keely Roth Exploring drivers of spectral variation at landscape scale: Structure, composition and function
Susan Ustin Mapping vegetation of the Sacramento Delta with AVIRIS-ng
Jay Stachowicz Genetic diversity, relatedness, and trait variation as determinants of plant coexistence and ecosystem functioning
Juan Ruiz Guajardo Host quality impacts colony-level aggression, survival, and the effectiveness of the defensive mutualism between Crematogaster mimosae (Santschi) and its host tree Acacia drepanolobium
Allison Dedrick Quantifying the interactions between management practices and the portfolio effect in salmon
Moria Robinson From soils to webs: Effects of environmental heterogeneity on specialization of plant-herbivore-parasitoid ecological networks
Andrew Siefert Testing the roles of niche differences and rhizobial mutualists in stabilizing coexistence of congeneric legumes
Jason Sadowski The influence of biological invasions and climate change on non-consumptive effects

Friday, August 12th

Name Title/Link
Val Eviner New mechanisms governing plant-soil feedbacks of native vs. exotic grassland species: Soil carbon depth distribution alters rooting distribution and seed production in a moisture-limited grassland
Jens Stevens The biogeography of fire regimes: A trait-based approach
Allison Simler Seedling regeneration dynamics following compounded disturbances: Wildfire and sudden oak death alter recruitment, mortality, and growth
Evan Batzer Perennial grasses in annual-dominated communities: Tradeoffs between invasive species suppression and fecundity
Chuanwu Chen The effects of seasonal changes and migratory versus resident status on the spatial structure of bird communities

useR! talk on teaching R

Here is a video recording of my talk from useR! 2016 on teaching R. It’s nominally about teaching a lot of students in an intensive format, but I think almost everything translates to traditional classes. If for whatever reason this video isn’t working out for you, here is the source.

This talk was just one in a great session. I’d highly recommend:

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A natural history idea for ecologists: the natural history supplement

At risk of rehashing what is in this very short paper (open access pdf here), a few colleagues and I have a simple idea for how to encourage natural history in current ecology and evolution. A whole bunch of notable folks, including Harry Greene, Josh Tewksbury, Paul Dayton and more have noted the decline in traditional natural history – the taking of observations, collecting specimens, and classes in zoology and botany – among academics over the last half decade or so. Their papers all deserve a read as they point out very real problems and quantify these declines.

Though these papers draw attention to the issue and make a very convincing case that it is an issue, they don’t offer realistic solutions. I’ll not overstate our case; our small idea won’t bring back botany classes where they once were taught or inspire people to create an insect collection at a college without one. However, we have an idea that may incentivize natural history study, at least a small bit. We propose that ecologists and evolutionary biologists create a natural history supplement with their paper to highlight potentially interesting observations and important natural history data.

An example of character displacement? A somewhat disjunct population of Abronia pogonantha in the coast range (left) is deep pink-purple, where populations I’ve looked at in the Mojave which grow near Abronia villosa (a deep pink purple species) are whitish or very light pink (right). I’m not going to investigate it, but I’ll include it in a natural history supplement so someone else might and I took specimens of these plants and sent them to an herbarium.

Anything of potential interest could go into this supplement (though it should not be used as support for the main assertions of a paper – any natural history of that sort still belongs IN the paper). This needn’t only apply to field studies, either – researchers working in greenhouses or in laboratories with colonies of microorganisms make important natural history observations, too – they are just as intimately familiar with their study systems as a field biologist.

We think that there are a few reasons why this small addition would be particularly important and useful. First and most obviously, these observations WILL be useful to someone down the line, somewhere, sometime. Even if it takes 50 years for someone to investigate a particular plant or insect, these observations of behavior, population size, flowering time, etc. in 2016 are an invaluable snapshot of what you saw when. Richard Primack and co.’s wonderful reanalysis of flowering time data which Thoreau gathered in the 1800’s are a perfect example of this type of use. Secondly, meta-analyses and comparative studies are commonplace and particularly informative and could use those life history data included in these supplement that wouldn’t make it into a paper on another aspect, but are likely data that many folks take instinctively.

Since we have the internet, archiving these sorts of things has never been easier. Many papers have a great deal of supplementary information (especially in short-form journals) and publishers have ways to archive it. While it doesn’t need to be done immediately, if this practice is adopted, a database of these natural history supplements could be compiled at any time.

This caterpillar, Sympisits [Lepipolysperscripta, is having a good year on both Antirrhinum vexillo-calyculatum (pictured) and A. cornutum. However, it is far more abundant on v-c. even when cornutum is the more abundant food. I’ll likely never write a paper on snapdragons, but if I did, this would be a perfect type of observation for the natural history supplement. 

Lastly, it incentivizes natural history observations and data. The “currency”, if you will, of academia is papers and citations. While including a natural history appendix doesn’t boost the first aspect, if the additional information in that supplement is of use to others, it can only boost your citation count and make your work more widely read.

If those sound like good or bad arguments, read the full paper (again, here), there is a good bit more in it. I’ll conclude by saying that I’ve written two of these, both for papers in Ecology (here and here) and they have been easy and enjoyable to write. Has anyone actually read them? I’m not sure (do tell if you have!). Maybe not, but that doesn’t seem particularly troubling to me – even if one person reads them and gets inspiration for a study or uses some data in an analysis decades after I’m gone, I’ll be happy. Plus, they were more fun to write than the main text of these papers. I focused both of these by describing briefly a great deal of natural history, hoping that someone studying one of these systems (especially the well-known ones, like Mimulus or Petunia or Nicotiana) would think about insect- or sand-entrapment.

On another level completely, I’m sure Ecology wouldn’t have let me use the fantastic quote “[Pholisma feels like] a squishy gummy bear covered in fuzzy sand covered hairs” in the main article 🙂 .

This stilt bug, Jalysus wickhami, moves easily on the sticky surfaces of many plants, including this weird, sticky fire-following monkeyflower, Mimulus bolanderi, by grabbing the glandular trichomes below their sticky heads. However, when I perturbed it for this photo, it got a bit of the sticky stuff on its front legs (visible in photo) and was visibly disoriented and had to groom it off with its other legs. Some cool papers have focused on movement on sticky plants, so the trichome grabbing behavior is well-known, but I might still include this in a supplement (with proper citations to those papers, of course).

A Shiny app to help interpret GW-Degree estimates in ERGMs

Most researchers are misinterpreting geometrically weighted degree (GWD) estimates in exponential random graph models (ERGMs) of networks. By a 3:1 ratio papers cite positive estimates of GWD as indicative of a popularity or centralization force; in fact, positive estimates indicate dispersion of edges.

Shiny app

Here is a Shiny app that allows you to examine the effects of GWD parameter and decay-parameter values on network degree distributions. On the app’s other tabs, it provides some intuition on how the GWD statistic works and how GWD and GWESP – which is used to model triadic closure – are confounded.


I presented this research at the 2016 Political Networks conference. Check out the poster, which includes a literature review showing how prevalent this mistake is, by clicking on the image.

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