Brief description of research
The general research theme is to
understand both why specific behavioral traits evolved and how these
traits function by integrating all four of Tinbergen’s questions
(development, mechanism, survival value and evolution) rather then
trying
to address them separately. Proximate mechanisms underlying behavioral
traits may be better understood when placed within the evolutionary
context and, equally, evolution of behavioral traits may be better
understood knowing
specific underlying mechanisms.
Most
of our recent work has focused on investigating adaptive variation in
cognition and the brain. Animals exhibit tremendous variation in
cognitive abilities and brain structure, both across and within
species, and our research aims to
understand both evolutionary
and proximate mechanisms underlying such variation by using comparative
and experimental approaches. We concentrated our research efforts
specifically on spatial memory and the hippocampus, a brain
structure
involved in spatial memory and used food-caching birds as our model.
Most scatter-hoarding birds such as chickadees are well known to use
spatial memory, at least in part, to recover previously made food
caches and these memories
are dependent on the hippocampus.
These birds depend on food caches for overwinter survival and such
dependence makes them a perfect target to investigate potential causes
of variation in memory and hippocampal structure and neural
processes.
Our goal has been to identify specific environmental features that may
influence selection strength on memory and to investigate whether
selection on memory resulted in enhanced memory associated with
specific changes in
hippocampal structure and neural
processes. We are specifically interested in determining whether
adaptive variation in memory and the hippocampus is based mainly on
experience-dependent plasticity or a product of inheritance, and we
use
a common garden approach to tackle this question. We also
currently expanded our research scope to genetics and we use hi-res
mRNA sequencing to test whether naturally occurring variation in memory
and the hippocampus is associated with
differential gene expression in the hippocampus.
Summary of our work on memory and the hippocampus in black-capped chickadees.
Our recent research addressed the following questions:
(1) Evolution of spatial memory and the hippocampus in food-caching birds
(2) Relationship between migratory behavior, memory and the hippocampus
(5) Effects of hormones on food-caching behavior, memory and the hippocampus
Most recently, my laboratory has been working on the following projects:
(1) Causes and consequences of variation in the hippocampus of individuals utilizing different spatial strategies (with Lara LaDage and Barry Sinervo; supported by NSF)
(2) The relationship between reliance on food caching, spatial memory and the hippocampus - an intraspecific comparison (supported by NSF)
(3) Effect of social environment on memory, hippocampal structure and neurogenesis (supported by NIH R01)
(4) Hippocampal neurogenesis and memory (supported by NIH R21)
Collaborators:
Dr. Anders Brodin; Department of Theoretical Ecology; University of Lund, Sweden.
I collaborate with Anders Brodin on my research on evolution of spatial memory and the hippocampus in food-caching birds,
and, in particular, on comparing hippocampal and brain size between Eurasian and North American species.
