Chase Barker, Utah Valley University
Central Research Question: Phylogenetic relationships of mayflies are still not very well known, however molecular and morphological data have begun to shed light on the relationships of these insects (Ogden et al. 2009). Our central question is to elucidate the phylogenetic relationships within the mayfly family Baetidae.
Purpose: The Baetidae are an important group of Mayflies because of their basal position relative to other mayfly families, in that they are a key to testing hypotheses of evolutionary trends, such as the origin of wings from gill-like structures. Our purpose is to generate molecular data in order to reconstruct a robust phylogenetic tree for the family Baetidae.
Research Methodology: Recent molecular and morphological analyses have examined relationships of some of the lineages of Baetidae distributed in different regions of the world (Gattolliat et al., 2008; Kluge, 1997; Monaghan et al., 2005; Nieto, 2010;). Most of these studies suggest two subfamilies, Baetinae and Cloeoninae. This study represents one of the largest (in terms of data) and most diverse (in terms of taxa) phylogenetic analysis performed on the family Baetidae to date. The dataset consists of more than 50 taxa sequenced for six genes (Nuclear 18S rDNA; Nuclear 28S rDNA; Histone 3, Mitochondrial COI, Mitochondrial 16S rDNA; and Mitochondrial 12S rDNA). DNA sequences were aligned in Muscle (Edgar 2004) and tree reconstruction and nodal support was performed under Maximum Parsimony, Maximum Likelihood, and Baysian frameworks.
Conclusion: The results indicate that the subfamilies were not strongly supported as monophyletic, contradicting conclusions from morphological data. Missing data in the data set might be contributing to low support across the tree. The phylogeny does not refute nor support the evolution of wings from gills.