Date of Award
Donald J. Stewart
bowfin, fish, genetics
The Bowfin, Amia calva Linneaus (1766), is a common Eastern North American fish and the last extant member of the order Amiiformes. By 1870, twelve additional species of Bowfin had been described from widely dispersed localities from lakes Huron and Champlain in the north to Charleston, SC, and New Orleans, LA, in the south. This diversity of nominal forms was synonymized into a single species, A. calva, by Jordan and Evermann in 1896. Since then, this monotypy hypothesis has been generally accepted, but never scientifically validated. Recently, this hypothesis was challenged when morphological analyses of Bowfin from Savanah River, SC, and Lake Ontario basins revealed that there appeared to be two distinct Bowfin species. This study further evaluates the monotypy hypothesis using molecular biological techniques. Analysis of the barcoding gene Cythochrome Oxidase I was used to phylogenetically compare specimens collected from the Great Lakes and the Carolinas. Sanger sequencing of that gene allowed for proper alignment and genetic classification of fish from each region. Maximum likelihood analyses of COI sequence data indicated the presence of distinct genetic clades from the Carolinas and the Great Lakes (divergence about 1%), and apparent distinction of two clades within the Carolinas (from NC and SC). This supports previous inferences based on morphology that there are two species of Bowfin -- from the Carolinas and from the Great Lakes. Results have important implications for delimiting potential extant species and, thus, improving taxonomy of the Bowfin and providing a critical foundation for conservation and management.
Clark, Madeline J., "Population Genetics of Bowfins (Amiidae, Amia spp.) Across the Laurentian Great Lakes and the Carolinas" (2015). Honors Theses. 90.