Incorporating fossils into hypotheses of insect phylogeny.

Fossils represent stem and crown lineages, and their inclusion in phylogenetic reconstruction influences branch lengths, topology, and divergence time estimation. In addition, paleontological data may inform trends in morphological evolution as well as biogeographic history. Here we review the incorporation of fossils in studies of insect evolution, from morphological analyses to combined 'total evidence' node dating analyses. We discuss challenges associated with fossil based phylogenetics, and suggest best practices for use in tree reconstruction.