Identifying appropriate units for conservation requires knowledge of evolutionary
patterns and risks of managing at different geographical and genetic scales. I examined
genetic diversity at different geographical scales among 11,400 rainbow trout
(Oncorhynchus mykiss) from 243 locations in 13 major river basins throughout much of
their range and among coho...
To assess the context dependence of kin discriminating
behavior, I examined kin-biased aggregation behavior in tadpoles
of R. cascadae in different ecological conditions. I manipulated food
distribution, predator presence, thermal heterogeneity, and
relatedness in a multifactorial mesocosm experiment. All four
factors interacted to influence tadpole dispersion. My results
suggest that...
I tested a theoretical model proposing that anemia
favors transmission of blood-borne parasites to vectors
by accelerating the blood-feeding rate. Using Aedes
aegypti, the yellow fever mosquito, initially, I was not
able to confirm this phenomenon either in an artificial
or a live system; anemia did not correlate with blood-feeding...
The effects of burial by tephra (volcanic aerial ejecta) on
forest understory plants were examined northeast of Mount St. Helens,
Washington, in the area where the 18 May 1980 eruption deposited
tephra but did not destroy canopy trees. At six sites along a tephra
depth gradient from 2-15 cm, understory...
In their modern context questions of heredity have come to be
closely aligned with theories of evolution because all such theories
require the presence of heritable variation. Thus the need for an
understanding of a source of variation and a mechanism for its inheritance
became very apparent with the general...
Aspects of the life history and ecology of the intertidal turf-forming
alga Rhodomela larix (Turner) C. Agardh were examined over a two
year period at several sites on the Oregon coast. Rhodomela occurred
over a broad tidal range and exhibited different growth and morphology
characteristics with respect to tidal height....
I experimentally test the hypothesis that the potential for selfing
increases with plant size in Mertensia ciliata (Boraginaceae), a self-compatible,
profusely-flowering perennial. This follows from the
premises that 1) pollen dispersal by pollinators between flowers is
limited, and 2) individual pollinators, in this study bumblebees, will
visit more flowers per...