These data were used in a simulation study to examine how honey bees distribute themselves across foraging landscapes. The ideal-free distribution and central-place foraging are important ecological models that can explain the distribution of foraging organisms in their environment. However, this model ignores distance-based foraging costs from a central place (hive, nest), while central-place foraging ignores competition. Different foraging currencies and cooperation between foragers also create different optimal distributions of foragers, but are limited to...
Both abiotic and biotic drivers influence species distributions. Abiotic drivers, such as climate, have received considerable attention, even though biotic drivers, such as hybridization, often interact with abiotic drivers. We sought to explore the (1) costs of co-occurrence for ecologically similar species that hybridize and (2) associations between ecological factors and condition to understand how abiotic and biotic factors influence species distributions. For two closely related and ecologically similar songbirds, black-capped and mountain chickadees, we...
Senescence is progressive bodily deterioration associated with declines in survival and fecundity in older age classes. There is great diversity in patterns of senescence across species, but these patterns can be difficult to compare formally due to variation in the absolute time scales in which species live and die: members of some species live for a matter of days, others for millennia. To address this issue, the ‘pace-shape’ approach was developed to decouple absolute time...
Productivity of riparian Populus forests: satellite assessment along a prairie river with an environmental flow regimeOscar Zimmerman, Stewart Rood & Flanagan Lawrence
In semi-arid regions, the growth and survival of cottonwoods (riparian Populus species) depend on river water supplementing the limited precipitation. Indicators of growth and productivity are needed to assess how altered streamflow regimes on regulated rivers impact cottonwood trees and the riparian forest ecosystems they support. Satellite imagery from the Landsat program was used to make historical assessments of ecosystem productivity in a riparian cottonwood forest along a regulated prairie river in southern Alberta, Canada...
Previous studies have demonstrated a correlation between longevity and brain size in a variety of taxa. Little research has been devoted to understanding this link in parrots; yet parrots are well-known for both their exceptionally long lives and cognitive complexity. We employed a large-scale comparative analysis that investigated the influence of brain size and life history variables on longevity in parrots. Specifically, we addressed two hypotheses for evolutionary drivers of longevity: the Cognitive Buffer Hypothesis,...
Introgression between Sphyrapicus nuchalis and S. varius sapsuckers in a hybrid zone in west-central AlbertaLibby Natola, Ashley Curtis, Jocelyn Hudon & Theresa Burg
Studying species interactions at hybrid zones allows biologists to understand the forces that promote speciation. Hybridization among Sphyrapicus nuchalis, S. varius, and S. ruber has long been acknowledged, and hybrid zones between S. nuchalis/S. ruber and S. varius/S. ruber have been characterized with both genetic and genomic data. Using a combination of next-generation Restriction Site-Associated DNA sequencing (RAD-Seq) and traditional genetic methods, we examined patterns of introgression in the poorly characterized S. nuchalis/S. varius contact...
Do habitat and elevation promote hybridization during secondary contact between three genetically distinct groups of warbling vireo (Vireo gilvus)?Amanda Carpenter, Brendan Graham, Garth Spellman & Theresa Burg
Following postglacial expansion, secondary contact can occur between genetically distinct lineages. These genetic lineages may be associated with specific habitat or environmental variables and therefore, their distributions in secondary contact could reflect such conditions within these areas. Here we used mtDNA, microsatellite, and morphological data to study three genetically distinct groups of warbling vireo (Vireo gilvus) and investigate the role that elevation and habitat play in their distributions. We studied two main contact zones and...
University of Lethbridge7
Denver Museum of Nature and Science1
New Mexico State University1
Royal Alberta Museum1
Government of Canada1
University of Northern British Columbia1
Max Planck Institute of Animal Behavior1
Max Planck Institute for Evolutionary Anthropology1
University of Colorado Boulder1