Biology Faculty Research, Publications and Presentations: Recent submissions
Now showing items 101-120 of 185
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Two centuries of multiple human impacts and successive changes in a North Atlantic food web
European colonization of North America, severely altered terrestrial and aquatic ecosystems alike. Here, we integrate archaeological, historical, and recent data to derive the ecological history of the Quoddy Region, Bay ... -
Long-term change in a meso-predator community in response to prolonged and heterogeneous human impact
Sharks and rays' abundance can decline considerably with fishing. Community changes, however, are more complex because of species interactions, and variable vulnerability and exposure to fishing. We evaluated long-term ... -
Spatiotemporal Patterns in Nest Box Occupancy by Tree Swallows Across North America
Data from the North American Breeding Bird Survey (BBS) suggest that populations of aerial insectivorous birds are declining, particularly in northeastern regions of the continent, and particularly since the mid-1980s. ... -
Seasonal and Age-Dependent Dietary Partitioning between the Great Black-Backed and Herring Gulls
Studies of seabird diets may reveal subtle ways in which sympatric species partition resources to facilitate co-existence. We studied the variability and partitioning of diets between the Herring (Larus argentatus) and ... -
Aggressive nest intrusions by male Humboldt Penguins
During observations at a breeding colony of Humboldt Penguins (Spheniscus humboldti), we noted five male penguins enter nests occupied by breeding pairs and engage in aggressive interactions with the resident adult. These ... -
Mitochondrial DNA variation, species limits, and rapid evolution of plumage coloration and size in the Savannah Sparrow
We compared sequences from two mitochondrial DNA (mtDNA) genes (ND2, ND3) in Savannah Sparrows (Passerculus sandwichensis; n = 112) sampled from Baja California (five sites), coastal Sonora and the continental range (eight ... -
Characteristics of predators and offspring influence nest defense by Arctic and Common Terns
Nest defense is a critical aspect of parental care that entails both costs and benefits. The purpose of this study was to examine patterns of nest defense in a colony of Arctic and Common Terns (Sterna paradisaea and S, ... -
The role of development, parental behavior, and nestmate competition in fledging of nestling Tree Swallows
Fledging (i.e. leaving the nest) in altricial birds is a major step toward independence. The timing of this important event may be influenced by nestling development, parental behavior, and sibling interactions. In this ... -
Sex-specific, seasonal foraging tactics of adult grey seals (Halichoerus grypus) revealed by state-space analysis
In many large pelagic animals, observing behavior is limited to observation by radio or satellite telemetry. In many cases, discriminating different behaviors from telemetry data has been a key, but often elusive, goal. ... -
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Observer Effects and Avian-Call-Count Survey Quality: Rare-Species Biases and Overconfidence
Wildlife monitoring surveys are prone to nondetection errors and false positives. To determine factors that affect the incidence of these errors, we built an Internet-based survey that simulated avian point counts, and ... -
Natural Selection, Variation, Adaptation, and Evolution: a Primer of Interrelated Concepts
Natural selection is an elegantly simple concept but one that can manifest in complex ways. I review how the basic model of single-trait viability selection has been extended to more complex forms of selection on multiple ... -
Conservation genetics as applied evolution: from genetic pattern to evolutionary process
Conservation genetics can be seen as the effort to influence the evolutionary process in ways that enhance the persistence of populations. Much published research in the field applies genetic sampling techniques to infer ... -
Adaptive Value and Costs of Physiological Plasticity to Soil Moisture Limitation in Recombinant Inbred Lines of Avena barbata
Costs are hypothesized to constrain the evolution of adaptive phenotypic plasticity, but they have been difficult to quantify because strong selection should eliminate costly genotypes from natural populations. However, ... -
Diazotrophic bacteria respond to Saharan dust additions
Three bioassay experiments were performed to study the effects of nutrient and Saharan dust additions on natural diazotrophic communities in the tropical North Atlantic Ocean. Samples for nucleic acid analysis were collected ... -
Compartmental models of nitrogen cycling in tropical and temperate marine environments
Time-course measurements of super(15)N tracer kinetics in particulate organic and in NH super(+) sub(4) pools from tropical and temperate regions were used to test several compartmental models describing the exchange of ... -
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Symmetry, change, perturbation, and observing mode in natural communities
Like a kaleidoscope, nature presents continuously fleeting images of natural communities. It has been difficult to discern patterns of community structure in these elusive images. For both theoretical and applied considerations, ... -
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Male and female pollination success in a deceptive orchid, a selection study
We carried out phenotypic selection analyses to assess the relative importance of several Horal traits, as well as microhabitat, in determining both male and female pollination success in a nonrewarding orchid (Cypripedium ...
