Functional redundancy has always been a problematic buzz word in ecology. People (including myself) liked to use it and intuitively got it , though there was such a variety of techniques and approaches to calculate it that comparing across studies was impossible. I’ve previously used deBello et al’s 2007 functional redundancy measure, but a broader framework was lacking.
Carlo Ricotta and colleagues have started to fill that gap with a reasonably coherent in the latest issue of Methods in Ecology and Evolution (see link below). It is a ripper of a issue by the way – I could write several more posts if I had the time. One noticeable thing missing are appropriate nulls models testing infer there is more redundancy in a community than expected by chance. Unless I’ve missed something, anyone want to write a short paper?