Synthetic Research

Ecology, like most sciences, produces a lot of empirical data and theory. On the empirical side, researchers focus on species or ecosystems and the result is a tremendous amount of data that has accumulated over the years but has often not been collated into a larger across species or across ecosystem perspective. Similarly theory can emerge that attacks specific aspects of a problem while one can look across theoretical research papers to ask if there are general rules behind some broad phenomena (e.g., population cycling where all mechanisms tend to operate around energy flux). These broader problems or perspecitves are synthetic and are as important as new studies to the development of a science. Ecology has been very good in the last decade or two at this “synthesis” and the McCann lab tends to enjoy working in this space. Below are some recent developing examples.

Food Production, Instability and Biodiversity Loss

Recently, through our ongoing interaction with the Centre for Ecosystem Management, Dr. Marie Gutgesell led a paper looking at how global food production impacts the food web structure and stability of ecosystem on and around the food production area. Herre, food production was both agricultural and fisheries. Towards this, we developed a review of relevant empirical data on how food webs were altered and examined all field results around this question (Fig. 1). You can read this paper here.

Fig. 1. Generic changes in food webs and properties due to food production.

2. Global Change Asymmetric Rewiring

Recent work in the lab by Dr. Timothy Bartley looked at climate change rewiring food webs (see paper here). Here, Dr. Bartley argued that climate tended to have spatial signature (was not uniform) and this was reflected in how food webs were impacted. As we have done more and more work on food webs under global change, PhD charlotte Ware noted this result re-appeared even more broadly. That is, global change, not just climate change, tends to have spatial signature (Fig. 2) that is reflected in the data. Here, Charlotte and collaborators are in the process of summarizing both theory and empirical results from isotopes, and energy flux estimates (via mass balance approaches) that have identified how food webs change in response to global changes broadly (e.g., land modification, climate change, nutrient pollution, invasives etc.). Paper due out soon.

Fig. 2. Schematic of global change impacts and the rewiring that follows tese changes.

3. The Population Dynamical Implications of a Fast-slow Life History Continuum

This work is underway but is interested in tying the pace of life, or fast-slow life history to population dynamics. Here, single species to interaction theory have broadly argued that high growth rates (e.g. discrete population models) or strong growth potential in consumers on resources (e.g., high growth rates relative to metabolic loss) tends to drive more boom and bust population dynamics. If this is true, and a fast life history increases its growth rate potential (i.e., rmax) then all else equal we would expect greater variation in population dynamics. There are possible exceptions to this hypothesis/prediction and beyond the scope of discussion here.

Towards this we (led by PhD student Reilly O’Connor) are summarizing theory and garnering a large quantity of time series and trait data to ask whether fast species are more variable or less stable. As smaller species tend to be faster, body size nay be expected to be a major axis for interpreting population dynamic variability. One intriguing aspect of this work is that one can also ask this question independent of body size following traits that produce faster species (e.g., higher relative metabolism yields high turnover and so may be expected to be a fast species for its body size).