Abstract
Conservation requires the accurate targeting of resources together with information on population processes. Molecular phylogenies can potentially contribute in both areas. Interspecific molecular phylogenies can identify clades undergoing rapid diversification or extinction and can assess the contribution of individual lineages to overall genetic diversity. Whether and how this should translate to conservation priorities is open to debate. Within species, molecular phylogenies along with information on allele frequencies can be used to identify evolutionarily significant population units or areas. In relation to population processes, molecular phylogenies may provide a perspective on population growth and connectivity over evolutionary time. As threatened species typically have undergone rapid changes in population size and/or migration rate, phylogeny-based estimates may be misleading about contemporary population processes. However, the comparison between historical and current estimates may identify significant changes to long-term trends, thus identifying population in need of urgent management. This information can potentially suggest strategies for managing declining or fragmented species, but this requires further theoretical and experimental study.