Invited Seminar at CES on 13 March 2020 at 11:00 am titled "Movement, frugivory, and seed dispersal" by Dr. Juan Morales from National University of Comahue

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Movement, frugivory, and seed dispersal
Dr. Juan Morales, National University of Comahue
Date & Time: 
13 Mar 2020 - 11:00am to 12:00pm
Event Type: 
Invited Seminar
CES Seminar Hall, 3rd Floor, Biological Sciences Building
Before the talk

Here I review the connections between animal movement and seed dispersal. Modelling seed dispersal by animals seems straightforward, we need a way to keep track of the position on the animal trough time and a clock for how long seeds travel with the animal. Simple models show how changing parameter combinations can result in very different seed dispersal kernels, including fat-tailed ones. When movement is more realistic, in the sense that is tied to the spatial distribution of resources, both seed consumption and dispersal kernels vary according to the neighborhoods of focal plants. Plants with many fruiting neighbors have high fruit removal rates but shorter dispersal distances. We empirically tested these theoretical predictions with a mistletoe species exclusively dispersed by an arboreal marsupial in Northern Patagonia. However, this is an unusual system because in general, plant communities interact with many species of frugivores. Recent empirical work shows that some frugivores may favor the consumption of rare fruits with important consequences for plant diversity maintenance. The mechanisms behind such patterns are still speculative but they could be related to frugivore physiology. Progress in hierarchical data analysis tools allows us to fit joint species frugivory models where species-level movement and foraging parameters are modeled as a function of species traits and their phylogenetic relationships. We have parameterized such models with bird movement and foraging data from tropical and temperate communities. In our model, plant-frugivore interactions emerge from frugivores’ behavior in a spatially explicit setting. This allows predicting how interactions rearrange after extinctions, and hence, to better quantify the vulnerability of plant species to partner loss. We can also have good estimates of frugivores’ role in seed dispersal. Overall, there has been great progress in data collection and modelling but we still need a better understanding of seed retention times, and of how bird physiology influences fruit choice. Further improvements in our ability to understand and predict seed dispersal by animals would probably also require considering within and among species agnostic behaviors