The research focus of the section is on the early evolution and higher-level phylogeny of birds.

In the past years, more than 90 new species of fossil birds were described from Paleogene (65-25 million years ago) deposits. Among these are numerous avian groups new to science, whose description extended the known diversity of the Paleogene avifauna. Many of these fossils further contributed to a better understanding of the evolution and historical biogeography of extant groups of birds.

n order to assess the phylogenetic affinities of these birds, the higher level phylogeny of extant birds also constitutes a research focus. New and meanwhile widely accepted phylogenetic hypotheses concern the affinities of, for example, owlet-nightjars (Aegothelidae) (Mayr 2002) and flamingos (Phoenicopteriformes) (Mayr 2004).

The head of the section is Associate Editor of the journal The Auk.