Phylogenetic Diversity
The Background
Phylogenetic diversity (PD) measures the evolutionary history captured by a set of species and therefore describes a fundamental aspect of biodiversity. As recognised by the Intergovernmental Science Policy Platform on Biodiversity and Ecosystem Services , the planet’s evolutionary heritage is a form of biodiversity that ensures options for future generations. The tree of life is a storehouse of potential benefits for humanity and by conserving PD, we conserve feature diversity (broadly, the full range of different evolutionary features of a set of species) and future options for humanity.
The Science
Phylogenetic diversity was designed as not only a simple measure of the degree of representation of evolutionary history by a given set of taxa, but also to enable associated calculations for decision-making (e.g. gains and losses or complementarity). PD is calculated by summing the length of all the branches connecting a given set of taxa, and therefore provides a measure to infer diversity, where the units of variation are features or traits of taxa. This link to “features” reflects the attempt, through PD calculations, to put value on variation where its value or functionality is not actually known. PD calculations therefore address a fundamental concern of biodiversity conservation.
The Need
At current extinction rates, we are facing unprecedented losses of PD across numerous taxonomic groups. There is a real need to incorporate PD in both species -focused and spatial conservation strategies if we are to avoid the impending loss of billions of years of evolutionary history.
Although there has been growing interest in using information on PD to inform conservation, widespread understanding of PD by practitioners and how to effectively incorporate it into conservation is still lacking. Metrics that capture evolutionary history have tended to be restricted to academic discussion and research, resulting in little guidance for stakeholders & managers on how to achieve phylogenetically-informed conservation approaches.
The Aim
The Phylogenetic Diversity Task Force provides leadership and guidance on the inclusion of phylogenetic diversity in conservation strategies. By providing the necessary scientific and technical expertise, we will promote wider adoption and greater understanding of this approach by conservation practitioners, decision-makers, and the public.
What we do
Develop and support knowledge-exchange and consultation between academics, practitioners, business and policy-makers interested in conserving evolutionary history.
Produce guidance documents that will address current challenges to the use of PD-based metrics (e.g. the EDGE metric).
Compile information on the applied use of PD in conservation around the world to assess the current extent of application of PD-based metrics.
Identify gaps in knowledge or application of PD-based metrics and encourage the scientific and conservation community to undertake scientific research and conservation applications to address these.