Meeting Abstract

P1.113  Wednesday, Jan. 4  Evolution of Pectoral Fins in Malawi Cichlids RUPP, Maxwell F.*; HULSEY, C. Darrin; Univ. of Tennessee, Knoxville; Univ. of Tennessee, Knoxville

In adaptive radiations such as Malawi cichlids there is a high degree of variation in the way pectoral fins are used in locomotion during feeding and other routine activities. To try and better understand the factors behind the evolution of pectoral fin musculature we wanted to address two questions: 1) Are there differences in the pectoral fin morphology between mbuna (rock-dwelling cichlids) and non-mbuna species? and 2) Do the mbuna show a faster rate of evolution in any aspect of their pectoral fin musculature or external fin structure when contrasted with non-mbuna? To do this, we compared the masses of the eight pectoral fin muscles for 45 species of Lake Malawi cichlid. Using this data and known phylogenetic relationships between the species, we were able to compare rates and patterns of macroevolution between mbuna and non-mbuna cichlids.