The Lecturer
Kevin Omland and his students use molecular phylogenies and population
genetic studies of closely related bird species to study character
evolution, speciation, and systematics. Recent research has focused on
the New World orioles (Icterus), as well as Holarctic ducks (Anas),
and ravens (Corvus corax). We are interested in plumage color
evolution, and a variety of topics related to recent speciation,
including lineage sorting, hybridization and building phylogenetic
trees of recently diverged species.
Abstract:
Phylogenetic ancestral state reconstruction can provide crucial
information for understanding the history of character evolution,
especially for helping us understand the gain AND LOSS of
characteristics. However, such approaches generally assume that the
phylogenies we use are correct, and most phylogenies of animal genera
are based on a single locus -- mitochondrial DNA. Our lab is
evaluating new "species tree" approaches based on multiple nuclear
loci to test mitochondrial trees. Although most nodes agree between
nuclear and mitochondrial DNA, we found one case of striking
incongruence due to cryptic hybridization. Our continued goal is to
use these phylogenies to study the history of behavioral evolution.
In New World orioles, we have strong evidence that the ancestral
oriole was a tropical species with females that sang and had elaborate
coloration. Our work illustrates that biases in how we think about
bird evolution and sexual selection in general may result from
research on migratory birds that happen to nest near traditional hubs
of behavioral research in places like the Northeast US, England and
Scandinavia.