Life Sciences Commons^™

A Cophylogenetic Analysis Of Fungus Gardening Ants And Their Symbiotic Fungi, Katherine Beigel

Biology Theses

Fungus-growing ants (Tribe Attini) and their fungal cultivars share a 50-million-year coevolutionary history. Large scale phylogenetic analyses depict a strong co-phyletic signal among ants and their farmed fungi yet fungus sharing among unrelated ant lineages is somewhat widespread. An overview of sharing has been hampered by a lack of genetic markers that exhibit intraspecific variation and surveys across geographic regions. For example, previous studies have shown similar sequences of the internal transcribed spacer (ITS) region of fungus in different species of Trachymyrmex, suggesting that these ant species are farming the same fungal clone. To examine whether this was a …

Reevaluating The Occurrence And Phylogeny Of The Pigtoe Unionid Mussels Fusconaia Askewi, Fusconaia Lananensis, Fusconaia Flava, And Pleurobema Riddelli In Texas, Charles J. Pratt

Biology Theses

The recent development of DNA-based species classification methods has led to the revision of many morphology-based species designations as genetic data has provided new information for species delineation. Analysis of standardized DNA ‘barcoding’ gene regions has proven particularly effective in resolving the taxonomic status of taxa that display phenotypic and habitat overlap.

Freshwater Unionid and Margaritiferid mussels comprise one of the most diverse aquatic taxa in North America, but are also among the most threatened, with over 70% of the approximately 300 native species considered at-risk or in decline. Although mussels face extensive threats from anthropogenic activity, conservation efforts have …