Exploring the developmental genetic basis of phenotypic plasticity in the lower pharyngeal jaw of cichlids

• Applicant: Helen Gunter, Ph.D.
• Subject Area: Evolutionary Cell and Developmental Biology (Zoology)
• Term: from 2010 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 170030029

Phenotypic plasticity is a significant source of morphological variation, which, in concert with natural selection can lead to speciation. However, the developmental and evolutionary factors that promote or constrain phenotypic plasticity remain largely unidentified. Thus the proposed research will examine an experimentally verified, developmentally plastic morphological innovation of cichlid fishes, with current molecular tools. The adult morphology of the lower pharyngeal jaw (LPJ) of Astatoreochromis alluaudi is diet-dependent, wherein a hard diet produces measurably thicker jaws than a softer diet. In this research project we plan to use complementary candidate and non-candidate gene approaches to examine the expression of genes known to influence bone remodeling and to identify additional upstream and downstream members of these pathways. This study also aims to determine the molecular basis of LPJ specification and morphogenesis because skeletal remodeling can involve a replay of embryonic developmental pathways however, early development of the cichlid LPJ is poorly characterized. This research will provide valuable insight into the molecular basis of phenotypic plasticity, and its contribution to evolution in an extremely diverse group of organisms, the East African cichlid fishes.

• DFG Programme: Research Grants