Mathematical Biology Seminar|
University of Utah
3:05PM, Wednesday, September 15, 2010
The demise of Darwin's finches?
|| The Galapagos Islands currently stand as one of the most well
preserved island ecosystems, with no known extinctions of avian or
mammalian species. However, a recently introduced parasitic fly, P.
downsi, threatens to change that standing. The larvae of P. downsi are
parasitic and blood feed on nestlings, reducing both growth and
survival. P. downsi has now been documented on 11 of 13 major islands
within the Galapagos and has been found in the nests of nearly every
land bird, including all species of Darwin's finches. I will discuss a
study we've performed using an experimental manipulation of parasite
abundance to assess fitness costs in a single species of Darwin's finch,
the medium ground finch. We have found noticeable variation in fitness
costs and parasite abundance over the course of this three-year study.
I will conclude by discussing how we have used these dynamic
fluctuations to create a simple model that examines both host and
parasite population persistence.