|
Mean-variance scaling of
population abundance
|
Ecology is
concerned with explaining patterns of animal and plant abundance. The combined
influence of environmental determinants and species specific life
history characteristics
determine how populations fluctuate across space and through time.
Changes in population
size are easy to observe, but quantifying the relationship between
population size
and
individual behavior is a challenge.
Taylor's power law describes how variance in abundance scales with mean
abundance and can be used to make  inference
about interactions among individuals. We are extending theory developed
in the lab that links the exponent of Taylor's Power law to the degree
of reproductive correlation exhibited in a population, and applying it
to address questions about life history trade-offs faced by fish and
plants. We are collaborating with Michael
Raghib-Moreno at Princeton, Chih-hao
Hsieh at National Taiwan University and Kirk Winemiller
at Texas A&M University on multiple projects.
|
|
| Optimal group size of Levy
foragers |
Much
study in ecology has been devoted to understanding what drives patterns
of foraging behavior. Recently, a body of work has suggested
that
the individual acquisition of resources is optimized through movement
characterized by a Levy distribution. A Levy distribution
describes a power law relationship between the length of foraging
paths and their frequency. The occurrence of long "flights" and scale
invariance are hallmarks of Levy processes.
In collaboration with Frederic Bartumeus at Princeton, we are working
to understand how the optimal behavior of individuals is affected by
group membership. In particular, we are identifyfing the
trade-offs associated with group foraging in a range of environments.
|
|
|
