DISSERTATION RESEARCH: Assessing early molluscan evolution with emphasis on aplacophorans

Auburn University, Auburn AL

Investigators

Abstract

With an estimated 200,000 living species, Mollusca is the second most species-rich animal group. Many molluscs are economically, ecologically, or biomedically important. Additionally, the molluscan body plan is extremely varied, ranging from slugs to clams to giant squid. Because of molluscs' variation, diversity and abundance in the fossil record, there has been great interest in identifying the primitive condition of the group for nearly 200 years. The worm-like mollusc group called Aplacophora (Latin for "without a shell") has long been thought to be important to understanding early molluscan evolution. However, little is known about the evolutionary history (phylogeny) within this mostly deep-sea group. This research aims to reconstruct aplacophoran phylogeny using a combination of traditional and cutting-edge, next-generation DNA sequencing technologies. New morphological data will be collected using traditional microscopy and characters will be mapped onto the phylogeny to infer primitive features of Aplacophora as well as Mollusca as a whole. Understanding how these animals have evolved will be of great interest to paleontologists and invertebrate biologists who have long sought to understand the early evolution of this diverse and fascinating group. Moreover, as molluscs are important models in the fields of neurobiology and parasitology, the results of this work will directly inform biomedical research.