Current studies of meadowlarks:
Eastern meadowlarks (Sturnella magna ) are one of the species of
Icterinae with little plumage dimorphism .
Both males and females have the bright ventral coloration illustrated
here; female coloration is almost as bright as that of males. A
phylogenetic analysis suggests that ancestors to eastern meadowlarks were
dimorphic, with females much duller in plumage color than males, so
brightly colored females apparently evolved relatively recently, in the
ancestor to the eastern meadowlark and the closely related western
meadowlark (S. neglecta .) In an effort to understand plumage
coloration, especially the evolution of bright coloration in females, I am
conducting a study of a population of eastern meadowlarks on the
University of Tennessee at Martin Experimental Farm, just north of the UTM
campus.
An additional goal of this study is to determine factors that affect
nesting success in this species, a ground-nesting grassland bird, in the
habitats where most meadowlarks currently breed -- pasture land, with
potential disturbance from large animal grazing, and hay fields, with
disturbance from mowing. These habitats typically have many potential
nest predators, some of which have been introduced (e.g. cats) or had
their populations increased (e.g. raccoons) as a result of human
activities. Finally, I will also use meadowlarks to continue my long-term
studies of icterine songs.
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