Phylogeny and biogeography in the evolution of migration: shorebirds of the Charadrius complex

Summary Aim We explore whether molecular phylogeny and biogeography can complement evolutionary ecology in developing a method to address a long‐standing issue in the evolution of migration: have migrations between breeding and non‐breeding grounds, which may be on different continents, evolved through origins in the breeding grounds with successive shifts of the non‐breeding distribution or vice versa ? Methods To accommodate the biology of migration, we treated breeding and non‐breeding distributions as characters to be mapped onto a phylogeny derived from mitochondrial DNA sequence data and so examined the ancestral home issue as a study in the direction of character evolution. Results Our main findings from applying this approach to a subset of the Charadrius complex of shorebirds (Aves: Charadriinae) are that a case can be made for shifts of breeding distributions having occurred in the ancestries of C. alexandrinus and C. veredus as those species evolved their present migration patterns. Our results also argue for a southern hemisphere origin (specifically South America) for the Charadrius complex as a whole. A South American origin implies other shifts in breeding distributions having occurred in the evolution of the species C. semipalmatus and C. vociferus. On applying the methods we developed for dealing with phylogenetic uncertainty, these results are reinforced and the merit of testing them further is suggested. Conclusions By way of a new approach to the evolution of migration, our study adds to a consensus emerging from the evolutionary ecology of migrant birds, arguing that shifts of breeding distributions are commonly, though not necessarily exclusively, involved in the evolution of migration.