Search Results - "Nolan, Val Jr"

Adaptation, Exaptation, and Constraint: A Hormonal Perspective by Ketterson, Ellen D., Nolan, Jr, Val

“…We approach conceptual issues in evolutionary biology from an endocrinological perspective, noting that single hormones typically act on several target tissues…”
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Acorn mast drives long-term dynamics of rodent and songbird populations by Clotfelter, Ethan D, Pedersen, Amy B, Cranford, Jack A, Ram, Nilam, Snajdr, Eric A, Nolan, Val Jr, Ketterson, Ellen D

“…Resource pulses can have cascading effects on the dynamics of multiple trophic levels. Acorn mast is a pulsed resource in oak-dominated forests that has…”
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Consequences of elevating plasma testosterone in females of a socially monogamous songbird: evidence of constraints on male evolution? by Clotfelter, Ethan D, O'Neal, Dawn M, Gaudioso, Jacqueline M, Casto, Joseph M, Parker-Renga, Ian M, Snajdr, Eric A, Duffy, Deborah L, Nolan, Val, Ketterson, Ellen D

“…To explore whether selection for testosterone-mediated traits in males might be constrained by costs of higher testosterone to females, we examined the effects…”
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more informative method for analyzing reproductive success by Murray, Bertram G., Nolan, Val

“…Few investigators have examined how a female's prior history (i.e., number of clutches laid previously and whether those nesting attempts were successful or…”
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Influence of Exogenous Testosterone on the Dynamics of Nestling Provisioning in Dark-Eyed Juncos by Clotfelter, Ethan D, Ray Chandler, C, Nolan, Val Jr, Ketterson, Ellen D

“…In many songbird species, application of exogenous testosterone (T) during the breeding season has the general effects of reducing male parental investment and…”
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Elevated testosterone reduces choosiness in female dark–eyed juncos (Junco hyemalis): evidence for a hormonal constraint on sexual selection? by Joel W. McGlothlin, Diane L. H. Neudorf, Joseph M. Casto, Val Nolan, Jr, Ellen D. Ketterson

“…), we tested whether experimentally enhancing female T would lead to a decrease in discrimination between two classes of males, one treated with T (T–males)…”
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Mouth Color Signals Thermal State of Nestling Dark-Eyed Juncos (Junco hyemalis) by Clotfelter, Ethan D., Schubert, Kristin A., Nolan Jr, Val, Ketterson, Ellen D.

“…In many species of birds, nestlings have brightly colored mouths. Some studies have found that mouth color is related to hunger, and may serve to solicit…”
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Testosterone Manipulation of Male Attractiveness has no Detectable Effect on Female Home-Range Size and Behavior During the Fertile Period by Neudorf, Diane L., Ziolkowski Jr, David J., Jr, Val Nolan, Ketterson, Ellen D.

“…Female dark‐eyed juncos (Junco hyemalis) are socially monogamous, but they engage in extra‐pair copulations (EPCs). We examined spatial activity and behavior…”
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The Effects of Experimentally Elevated Testosterone and Food Deprivation on Food Consumption and Prey Size Preferences in Male Dark-Eyed Juncos (Junco hyemalis, Emberizidae: Passeriformes) by Clotfelter, Ethan D., Nolan Jr, Val, Ketterson, Ellen D.

“…Numerous studies have shown that the experimental elevation of circulating levels of testosterone reduces parental behaviour in male birds, particularly the…”
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CORRELATIONAL SELECTION LEADS TO GENETIC INTEGRATION OF BODY SIZE AND AN ATTRACTIVE PLUMAGE TRAIT IN DARK-EYED JUNCOS by McGlothlin, Joel W, Parker, Patricia G, Nolan, Val, Ketterson, Ellen D

“…When a trait's effect on fitness depends on its interaction with other traits, the resultant selection is correlational and may lead to the integration of…”
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Effects of testosterone on use of space by male dark-eyed juncos when their mates are fertile by CHANDLER, C.RAY, KETTERSON, ELLEN D, NOLAN, JR, VAL

“…Testosterone is an important determinant of spatial activity in male birds. Using radiotelemetry, male dark-eyed juncos,Junco hyemaliswere followed during the…”
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Steroid Hormones and Immune Function: Experimental Studies in Wild and Captive Dark‐Eyed Juncos (Junco hyemalis) by Casto, Joseph M., Nolan, Jr, Val, Ketterson, Ellen D.

“…Monogamous and polygynous male songbirds generally differ in their breeding season profiles of circulating testosterone. Testosterone level spikes early in the…”
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Hormones and Life Histories: An Integrative Approach by Ketterson, Ellen D., Nolan, Val

“…This article, which focuses on hormones and the diverse effects they have on behavior and physiology, raises evolutionary questions that hormonal studies…”
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The Evolution of Clutch Size. I. An Equation for Predicting Clutch Size by Murray, Bertram G., Nolan, Val

“…We derive an equation for calculating the clutch sizes of birds and other long-lived animals from Murray's (1979) theory on the evolution of clutch size. For…”
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Female ornamentation and male mate choice in dark-eyed juncos by Wolf, Wendy L, Casto, Joseph M, Nolan, Val, Ketterson, Ellen D

“…Traits that enhance attractiveness in one sex may or may not influence attractiveness in the other. In the dark-eyed junco, Junco hyemalis, outer tail feathers…”
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Testosterone increases activity but not daily energy expenditure in captive male dark-eyed juncos, Junco hyemalis by Lynn, Sharon E., Houtman, Anne M., Weathers, Wesley W., Ketterson, Ellen D., Nolan, Val

“…Plasma testosterone (T) levels in male dark-eyed juncos peak early in the breeding season, then decline. If T enhances opportunities for reproductive success,…”
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Erratum by Ketterson, Ellen D., Nolan, Jr, Val

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Offspring Sex Ratio Is Unrelated to Male Attractiveness in Dark-Eyed Juncos (Junco hyemalis) by Grindstaff, Jennifer L., Buerkle, C. Alex, Casto, Joseph M., Nolan, Val, Ketterson, Ellen D.

“…Sex allocation theory predicts that parents should bias investment toward the offspring sex that confers higher relative fitness on the parents. When variance…”
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Effects of Experimentally Elevated Testosterone on Plasma Corticosterone and Corticosteroid-Binding Globulin in Dark-Eyed Juncos ( Junco hyemalis) by Klukowski, Lori A., Cawthorn, J.Michelle, Ketterson, Ellen D., Nolan Jr, Val

“…An earlier study of free-living male dark-eyed juncos found an increase in plasma corticosterone (B) in response to experimental elevation of plasma…”
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Influence of experimentally elevated testosterone on nest defence in dark-eyed juncos by CAWTHORN, J.MICHELLE, MORRIS, DANA L, KETTERSON, ELLEN D, NOLAN, VAL

“…Testosterone affects the allocation of reproductive effort in male birds. Elevated testosterone causes male dark-eyed juncos,Junco hyemalis, to decrease care…”
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