Heather R.L. Lerner, M.S.,
Ph.D. candidate
University of Michigan Department of Ecology and Evolutionary Biology
Email:
hlerner@umich.edu Lab Phone:
734-763-0310 Address:
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Research Interests Projects Publications C.V.
My
research uses molecular phylogenetics and phylogeography to investigate
patterns and processes of avian speciation, particularly those of birds of
prey. Phylogenies are the
foundation of modern methods in evolution as they provide a framework for
studying the evolution of behavioral and morphological traits and
biogeographic impacts on speciation.
Furthermore,
molecular phylogenetic methods are useful in identifying monophyletic
groups which may be priorities for species conservation. In
the very general sense I am interested in the assessment of natural
genetic variation harbored by avian populations, and how it is relevant to
their evolution, natural history, and survival. My long-term goal
is to understand how ecology and genetics affect the persistence of
raptor species through time, and use this information to make informed
decisions pertinent to the conservation of biodiversity, not just within
the Accipitridae.
Accipitridae and other raptors are valuable indicators of
environmental health as they are among the first and most visible taxa to
show the effects of environmental degradation (e.g. peregrine falcon and
bald eagle declines of the late 20th century). Furthermore, since sites occupied
by raptors are associated with high species diversity, studying raptors
can also provide insights relevant to the health of whole ecosystems. My central hypotheses are that
(1) lower genetic variability exists in most birds of prey resulting at
least partially from their characteristically long generation times and
low population sizes, such that raptors are highly prone to extinction
when population declines are sustained, but are able to survive repeated
short bottlenecks without great losses in genetic diversity or
evolutionary potential; and, (2) high levels of morphological plasticity
allow birds of prey to both colonize new environments and survive
disruptions in their environments. The objectives of my current work are to
determine the historical patterns and timing of extinction and speciation
in the Accipitridae, estimate the levels of genetic diversity within and
among Accipitrid species for comparison with other non-predatory birds,
identify morphological traits associated with high levels of
diversification or extinction and develop a working hypothesis for
divergence time estimates among major accipitrid groups that can be used
to estimate mutation rates for population-level studies of raptors. The rationale for this research is
that once we ascertain basic traits that have contributed to the
extinction of raptor species, we shall be able to predict how future
changes may affect populations of birds of prey; and thus, gain a better
understanding of how anthropogenic changes affect raptors before more
species are lost.
Furthermore, a deep understanding of the evolutionary history of
the Accipitridae will provide insights into the basic mechanisms of
evolution that could be broadly applicable to environments occupied by
raptors and to top-predators in other organismal
groups. |