Life Sciences Commons^™

Infestation Intensities, Attachment Patterns, And The Effect On Host Contest Behavior Of The Tick Ixodes Pacificus On The Lizard Sceloporus Occidentalis, Dylan M. Lanser

Master's Theses

Parasites often have profound effects on the survival and evolution of their hosts, and hence on the structure and health of entire ecosystems. Yet basic questions, such as the degree of virulence of a given parasite on its host, and factors influencing which hosts in a population are at the greatest risk of infection, are vexingly difficult to resolve. The western blacklegged tick-western fence lizard (Ixodes pacificus-Sceloporus occidentalis) system is important, primarily because I. pacificus, a vector of the Lyme disease spirochete Borrelia burgdorferi, is dependent on S. occidentalis for blood meals in its subadult stages, …

Play Behavior And The Development Of Boldness And Caution In Juvenile Belding’S Ground Squirrels (Urocitellus Beldingi), Madelene Shehan

Master's Theses

The ubiquity of play among juvenile mammals suggests it provides adaptive benefits, potentially through influences on the development of temperament in young animals. Juvenile Belding’s ground squirrels (Urocitellus beldingi) must balance competing demands for boldness and caution imposed by the fundamental trade-off between their short active season and their vulnerability to predation. In this study, I evaluated whether play helps to facilitate the development of an appropriate balance between boldness and caution in juvenile U. beldingi.I observed the play behavior of juvenile U. beldingiand conducted flight-initiation distance tests to measure boldness-caution at the beginning and toward …

Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell

Master's Theses

Global biodiversity is declining as a direct result of anthropogenic climate change. Ectothermic species have become focal organisms for studying the ecological effects of altered climates due to the clear relationship between environmental temperatures and ectotherms’ basic physiological functions. Historically, examinations of these effects have focused heavily on heliothermic lizards, and most others have tended to focus on single populations or sympatric species within a single community. Addressing the longterm energetic implications of environmental temperature variation will provide valuable insight into the cascading physiological effects that certain populations or species may experience as a result of altered climates.

In this …