(guest post from authors Kate Weiss and Courtenay Ray) – congratulations to them for a 100% student-authored paper!
Our new paper in Ecography seeks to provide functional ecologists with guidance when working across taxa. Functional traits are aspects of phenotypes at the individual scale that respond to or interact with the environment, and have the potential to help us identify which characteristics may correspond with species invasion or climate change. Functional traits can also be used to understand ecological patterns across a variety of taxa. However, different disciplines have created their own unique approaches, definitions, and techniques when conducting functional ecological research. This can create discord when identifying broad trends across the tree of life. We developed a guide to synthesize definitions and approaches to best support functional ecological research on community assembly across taxa.
We unify definitions by including behavior, physiology, and morphology as phenotypic components worthy of investigation. We then discuss how functional traits exist along a continuum. One end of the continuum reflects traits that influence organismal fitness and performance (response traits), while the other end includes traits that influence ecosystem processes or species interactions (effect traits). When researching community assembly, we recommend focusing on response traits.
To understand community assembly across taxa, some argue for using the same traits across species. However, the difficulty with this is that similar traits may have different functions in different taxa. We argue for comparing traits that capture similar functions, even if the structures themselves diverge. This allows for comparisons of broad trends in functional traits across taxa.
To identify which functions to compare, we recommend linking traits to community assembly processes (i.e., speciation, selection, dispersal, and drift). This is because communities often form in effect of how environmental conditions filter traits. By incorporating community assembly explicitly in trait selection, and at similar scales (i.e., by comparing data across the same taxonomic rankings), researchers may be better situated to determine broad trends in community assembly. When data is lacking for certain taxa, we suggest using either data reduction and interpolation techniques or incorporating demographic, life history, or other data that captures fitness and organismal performance.
Our paper introduces a diversity of researchers to the complex literature surrounding multi-taxa functional ecology and guides functional ecologists in drawing comparisons across taxa. We hope our article will support scientists in the identification of broad trends in community assembly to better approach generality in community ecology.