ABSTRACT PI: Basolo Proposal number: 9629318 A Comparative Study of a Preference in Live-bearing Fishes Research Component: This project will investigate the historical basis of a preference for a male trait and examine changes in the preference over time. Preferences can appear prior to male traits, and can affect male traits when they arise. Although there is mounting evidence that such a mechanism for selection can be important, little is known about the history of such preferences and how they might change. Males in many fish species in the genus Xiphophorus possess an elongated portion of the caudal fin, the sword. Females in this genus, as well as in the sister genus which lacks a sword, have a preference for swords. These results, combined with historical evidence, suggest that this preference appeared prior to the appearance of a sword. The proposed research will test whether the strength of the preference favoring a sword has changed in the history of this group of fishes and their relatives. Education Component: The use of both established and innovative teaching methods are proposed as a means to broaden and improve student learning. To enhance learning in an Animal Behavior lecture course, cooperative learning groups, an electronic news group, a course world-wide web site, and email interchanges with scientists at other universities are proposed. To increase the students appreciation for and understanding of animal behavior, a laboratory-based course, Experimental Methods in Animal Behavior, will be developed. Principles covered will include classical methods, as well as new techniques, including paternity analysis and the use of digitally- altered videos to test behaviors.
