Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Biology

PDF

University of Kentucky

Aggression

Articles 1 - 2 of 2

Full-Text Articles in Entire DC Network

Environmentally Realistic Exposure To The Herbicide Atrazine Alters Some Sexually Selected Traits In Male Guppies, Kausalya Shenoy Feb 2012

Environmentally Realistic Exposure To The Herbicide Atrazine Alters Some Sexually Selected Traits In Male Guppies, Kausalya Shenoy

Biology Faculty Publications

Male mating signals, including ornaments and courtship displays, and other sexually selected traits, like male-male aggression, are largely controlled by sex hormones. Environmental pollutants, notably endocrine disrupting compounds, can interfere with the proper functioning of hormones, thereby impacting the expression of hormonally regulated traits. Atrazine, one of the most widely used herbicides, can alter sex hormone levels in exposed animals. I tested the effects of environmentally relevant atrazine exposures on mating signals and behaviors in male guppies, a sexually dimorphic freshwater fish. Prolonged atrazine exposure reduced the expression of two honest signals: the area of orange spots (ornaments) and the …


Shelter Availability, Occupancy, And Residency In Size-Asymmetric Contests Between Rusty Crayfish, Orconectes Rusticus, Nathan M. Klar Jan 2010

Shelter Availability, Occupancy, And Residency In Size-Asymmetric Contests Between Rusty Crayfish, Orconectes Rusticus, Nathan M. Klar

University of Kentucky Master's Theses

Contest outcomes are usually determined by differences in resource holding potential, the social histories of the combatants, and perceptions of resource value. One understudied aspect of gaining an advantage is the residency effect. Prior occupancy of a particular place can affect the knowledge and motivation of the resident. There could be a tactical advantage in knowing the terrain or an increased willingness to fight to maintain control of a familiar area. In this study we evaluated the importance of shelter residency effects relative to size differences between rusty crayfish (Orconectes rusticus) as potential competitors for access to shelter. …