Life Sciences Commons^™

Impact Of An Ecological Factor On The Costs Of Resource Acquisition: Fighting And Metabolic Physiology Of Crabs, L. U. Sneddon, F. A. Huntingford, A. C. Taylor

Ethology Collection

1. Current game theory models and recent experimental evidence suggests that the strategy an animal adopts in agonistic encounters is determined by individual state. Therefore manipulation of an individual’s state should elicit different behavioural responses. In this paper, mechanisms are examined that underlie state-dependent strategies using Shore Crabs, Carcinus maenas, and how, by altering the environment, behaviour and physiology are affected.
2. Fights were staged between pairs of male crabs under normoxic and severely hypoxic (< 15 torr) conditions to determine if the metabolic costs of fighting and resource acquisition are affected by water P_O2. After fighting, blood and tissue samples from each crab were taken and analysed for metabolites associated with anaerobiosis (L-lactate, glucose and glycogen).
3. The spectrum …

A Comparison Of Encephalization Between Odontocete Cetaceans And Anthropoid Primates, L. Marino

Veterinary Science and Medicine Collection

There have been very few studies of brain size and encephalization in cetaceans and essentially none that have made direct quantitative comparisons of cetaceans and another mammalian group using large normative samples. In the present study two different measures of encephalization were calculated and used to rank and compare 21 odontocete species and 60 anthropoid primate species. Comparisons were made both within and between the two groups. Results show that the encephalization level of Homo sapiens is still extraordinary relative to that of nonhuman species. Nevertheless, a subset of delphinid odontocetes are significantly more highly encephalized than the most highly …

Translocation Effects On The Behavior Of Black-Tailed Prairie Dogs (Cynomys Ludovicianus), John P. Farrar, Karin L. Coleman, Marc Bekoff, Eric Stone

Ethology Collection

We examined the effects of translocation on Black-tailed prairie dog (Cynomys ludovicianus) anti-predator behavior by recording response distances and response times to a human intruder in three colonies containing native, translocated, and combined native and translocated prairie dogs. The translocated prairie dogs barked alarms and concealed themselves at significantly greater intruder distances than mixed or native colonies. However, individuals in different colonies did not differ in the time taken to return to a burrow, to conceal themselves after a human approached the colony, or in the time elapsed after concealment until an animal reappeared. Translocated prairie dogs exhibited nearly twice …