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Full-Text Articles in Life Sciences

Estrogen Receptors In The Medial Amygdala Inhibit The Expression Of Male Prosocial Behavior, Bruce S. Cushing, Adam Perry, Sergei Musatov, Sonoko Ogawa Oct 2008

Estrogen Receptors In The Medial Amygdala Inhibit The Expression Of Male Prosocial Behavior, Bruce S. Cushing, Adam Perry, Sergei Musatov, Sonoko Ogawa

Biology Faculty Research

Studies using estrogen receptor alpha(ER) knock-out mice indicate that ER alpha masculinizes male behavior. Recent studies of ER alpha and male prosocial behavior have shown an inverse relationship between ER alpha expression in regions of the brain that regulate social behavior, including the medial amygdala (MeA), and the expression of male prosocial behavior. These studies have lead to the hypothesis that low levels of ER alpha are necessary to "permit" the expression of high levels of male prosocial behavior. To test this, viral vectors were used to enhance ER alpha in male prairie voles (Microtus ochrogaster), which display high levels …


Grazing And Virus-Induced Mortality Of Microbial Populations Before And During The Onset Of Annual Hypoxia In Lake Erie, Christopher J. Gobler, Timothy W. Davis, Sarah N. Deonarine, Matthew A. Saxton, Peter J. Lavrentyev, Frank J. Jochem May 2008

Grazing And Virus-Induced Mortality Of Microbial Populations Before And During The Onset Of Annual Hypoxia In Lake Erie, Christopher J. Gobler, Timothy W. Davis, Sarah N. Deonarine, Matthew A. Saxton, Peter J. Lavrentyev, Frank J. Jochem

Biology Faculty Research

Lake Erie is the most productive of the North American Great Lakes and experiences annual periods of hypolimnetic hypoxia with unknown consequences for the microbial food web. We established the abundances and mortality rates of microbes in Lake Erie during thermal stratification and determined how they varied with changes in bottom-water dissolved oxygen concentrations. The microbial plankton community (heterotrophic bacteria, Cyanobacteria, eukaryotic phytoplankton, nanozooplankton, microzooplankton) was quantified in surface and bottom waters along with measurements of herbivory and bacterivory rates on eukaryotic and prokaryotic picoplankton and rates of viral lysis of bacteria. High rates of grazing mortality of prokaryotic picoplankton …


Sticky Gecko Feet: The Role Of Temperature And Humidity, Peter H. Niewiarowski, Stephanie Lopez, Liehui Ge, Emily Hagan, Ali Dhinojwala May 2008

Sticky Gecko Feet: The Role Of Temperature And Humidity, Peter H. Niewiarowski, Stephanie Lopez, Liehui Ge, Emily Hagan, Ali Dhinojwala

Biology Faculty Research

Gecko adhesion is expected to be temperature insensitive over the range of temperatures typically experienced by geckos. Previous work is limited and equivocal on whether this expectation holds. We tested the temperature dependence of adhesion in Tokay and Day geckos and found that clinging ability at 12 degrees C was nearly double the clinging ability at 32 degrees C. However, rather than confirming a simple temperature effect, our data reveal a complex interaction between temperature and humidity that can drive differences in adhesion by as much as two-fold. Our findings have important implications for inferences about the mechanisms underlying the …


Sex-Role Reversal In Song? Females Sing More Frequently Than Males In The Streak-Backed Oriole, J. J. Price, L. Yunes-Jimenez, M. Osorio-Beristain, K. E. Omland, Troy G. Murphy May 2008

Sex-Role Reversal In Song? Females Sing More Frequently Than Males In The Streak-Backed Oriole, J. J. Price, L. Yunes-Jimenez, M. Osorio-Beristain, K. E. Omland, Troy G. Murphy

Biology Faculty Research

Birds in which both sexes produce complex song are more common in the tropics than in the temperate north, where typically only males sing. Yet surprisingly little is known about female song characteristics in most tropical species. Here we present a comparison of female and male singing behaviors in the Streak-backed Oriole (Icterus pustulatus), a tropical songbird in which both sexes perform solo songs. Females sing much more frequently than males and produce songs with similar acoustic complexity. Rates of singing by both sexes were higher during breeding than postbreeding while the rates of most other vocalizations did …


A New Species Of Giant Sengi Or Elephant-Shrew (Genus Rhynchocyon) Highlights The Exceptional Biodiversity Of The Udzungwa Mountains Of Tanzania, F Rovero, G B. Rathbun, A Perkin, T Jones, David O. Ribble, C Leonard, R R. Mwakisoma, N Doggart Feb 2008

A New Species Of Giant Sengi Or Elephant-Shrew (Genus Rhynchocyon) Highlights The Exceptional Biodiversity Of The Udzungwa Mountains Of Tanzania, F Rovero, G B. Rathbun, A Perkin, T Jones, David O. Ribble, C Leonard, R R. Mwakisoma, N Doggart

Biology Faculty Research

A new species of sengi, or elephant-shrew, is described. It was discovered in the northern Udzungwa Mountains of Tanzania in 2005. Sengis (Order Macroscelidea, super-cohort Afrotheria) include four genera and 15 species of mammals that are endemic to Africa. This discovery is a significant contribution to the systematics of this small order. Based on 49 camera trap images, 40 sightings and five voucher specimens, the new sengi is diurnal and distinguished from the other three species of Rhynchocyon by a grizzled grey face, pale yellow to cream chest and chin, orange-rufous sides, maroon back and jet-black lower rump and thighs. …


Effects Of Population Size And Density On Pollinator Visitation, Pollinator Behavior, And Pollen Tube Abundance In Lupinus Perennis, Christopher E. Bernhardt, Randall J. Mitchell, Helen J. Michaels Jan 2008

Effects Of Population Size And Density On Pollinator Visitation, Pollinator Behavior, And Pollen Tube Abundance In Lupinus Perennis, Christopher E. Bernhardt, Randall J. Mitchell, Helen J. Michaels

Biology Faculty Research

Both the number and the density of flowering plants in a population can be important determinants of pollinator abundance and behavior. We report the joint effects of population size and density on pollinator visitation and pollination success for Lupinus perennis (Fabaceae). Focusing on five pairs of populations, we matched one small population (125-800 flowering plants) with one distinctly larger population (1000-3000 flowering plants). In these pairs, population size did not affect pollinator communities or pollination success. All measures of pollination success increased significantly with density. Only bee behavior (number of flowers probed per inflorescence) exhibited a significant interaction of size …


Lack Of Assortative Mating For Tail, Body Size, Or Condition In The Elaborate Monomorphic Turquoise-Browed Motmot (Eumomota Superciliosa), Troy G. Murphy Jan 2008

Lack Of Assortative Mating For Tail, Body Size, Or Condition In The Elaborate Monomorphic Turquoise-Browed Motmot (Eumomota Superciliosa), Troy G. Murphy

Biology Faculty Research

Elaborate male and female plumage can be maintained by mutual sexual selection and function as a mate-choice or status signal in both sexes. Both male and female Turquoise-browed Motmot (Eumomota superciliosa) have long tails that terminate in widened blue-and-black rackets that appear to hang, unattached, below the body of the bird. I tested whether mutual sexual selection maintains the Turquoise-browed Motmot’s elaborate tail plumage by testing the prediction that mating occurs in an assortative manner for tail plumage. I also tested whether assortative mating occurs for body size, a potential measure of dominance, and for phenotypic condition, a …


Display Of An Inedible Prop As A Signal Of Aggression? Adaptive Significance Of Leaf-Display By The Turquoise-Browed Motmot, Eumomota Superciliosa, Troy G. Murphy Jan 2008

Display Of An Inedible Prop As A Signal Of Aggression? Adaptive Significance Of Leaf-Display By The Turquoise-Browed Motmot, Eumomota Superciliosa, Troy G. Murphy

Biology Faculty Research

The incorporation of an inedible object (prop) into a behavioral display is rare among birds. Only four avian taxa have been reported to display with a prop, and in all studied species, prop use has been found to play a role in mate acquisition. However, little is known about the context and adaptive significance of prop use by the motmots. Both male and female motmots perform a leaf-display, whereby a leaf is held horizontally in the tip of the bill for an extended period. I collected observational data on leaf-display by the turquoise-browed motmots (Eumomota superciliosa) to investigate …