Ongoing work

I have four main themes of ongoing and future work that explore novel applications of phylogenetic data and methods in the fields of ecology, evolution, and conservation. This work is still on-going, and so please take a look at my past work for more papers, and email me if anything catches your eye.

Trait evolution

Analysing leaf shape using stalkless: detecting shape in a noisy background
Analysing leaf shape using stalkless: detecting shape in a noisy background

The rate at which species adapt to new environmental conditions is limited by the rate of functional trait evolution. We have a good understanding of broad patterns of evolution in macro-fauna, and strong quantitative frameworks to measure trait evolution. Yet there has been no global synthesis of plant trait evolution, despite some studies of many species with only a handful of traits and vice-versa. I am describing broad patterns of trait evolution in more than 150 global plant traits in the TRY database. By quantifying the evolutionary correlations and trade-offs among traits, I hope to understand the evolutionary potential for adaptation to global change. I plan to use new non-linear models of trait evolution to test whether past mass extinctions affected rates of trait evolution, and thus help predict how ecosystems will respond to the ongoing mass extinction. I am also developing collaborations with the Natural History Museum in London to examine changes in butterfly wing morphology over the past century using my stalkless program.
Outputs so far: sTEP working group (with Jeannine Cavender-Bares) at sDIV, stalkless image analysis pipeline

Eco-phylogenetics

My R package 'pez' contains a number of new eco-phylogenetic methods and tools
My R package ‘pez’ contains a number of new eco-phylogenetic methods and tools

Eco-phylogenetics represents an attempt to link the macro-evolutionary processes that act on clades to their present-day ecological structure. In my own work, I have linked diversification rates to the ecological structure of clades, permitting ecological prediction from evolutionary pattern. Yet most of the progress in the field has used phylogeny as proxy for functional traits. I am challenging this paradigm by using phylogeny to identify clades with different ecological structures, and then test whether they have a different tempo or mode of evolution 19 using independent functional trait data. To do this, I have developed an extension of existing approaches that partitions β-diversity (variation in assemblage composition) among clades within a phylogeny, and am testing it with tropical plant and global mammal systems. I am beginning to work with an Arctic plant system, exploring how phylogeny can provide predictions about the dynamics of species brought into contact by rapid environmental change.
Outputs so far: pez R package

Integrated diversification and ecological modelling

Conceptual overview of SISEPhyS model
Conceptual overview of SISEPhyS model

It is difficult to understand past evolutionary processes because they are finished, yet if ecology is the outcome and determinant of evolution we can parameterise evolutionary process with ecological data. Using Approximate Bayesian Computation, I am developing an integrative model to measure environmental filtering processes that structure communities on the basis of species’ traits. I call this model ‘SISEPhyS’, and it predicts the eco-phylogenetic structure of assemblages’ compositions and trait distributions. While it is similar to other biodiversity models, by not requiring an explicit likelihood framework the model estimates parameters from empirical data. I believe it is the first to quantify evolutionary diversification as a function of environmental filtering, an inherently ecological trait-based process that current models do not incorporate. By incorporating trait evolution and dispersal, and modelling extinction and speciation as an emergent property of environmental filtering, I’m hoping to predict species’ future responses to climate change and other environmental drivers.
Outputs so far: prototype SISEPhyS code (full code available on request)

Conservation and restoration

Map of Britain highlighting areas with potentially dangerous species. Part of my EDAM conservation prioritisation scheme
Areas of Britain with potentially dangerous species. Part of my EDAM conservation prioritisation scheme

It is time that makes historical sites like castles so intuitively priceless to humans, and phylogeny can reveal the millions of years of time that make species intuitively valuable. Many of the empirical and methodological advances I have described above have implications for predictions of future change, but I strongly believe phylogeny itself can directly inform conservation decision-making. I have already prioritised the British flora using my EDAM approach, which incorporates phylogeny, threat, and uncertainty in both. While I have briefly described in print how eco-phylogenetic approaches can help assess ecosystem health and plan restoration programmes, I am developing a more thorough framework for application in conservation. Applying my EDAM and eco-phylogenetic methods to other ecosystems is a relatively simple yet important task, and one I would like to tackle with undergraduate students. Contact me if you’re interested!
Outputs so far: EDAM prioritisation list and approach, restoration eco-phylogenetic framework (in press, no pre-print yet!)