The Heritability, Developmental Determination, and Evolutionary Significance of Mandible Length in the Zebrafish (Danio rerio) and other Danionine Fishes
Research Mentor(s)
W. James Cooper
Description
Jaw shape plays a significant role in determining feeding niche in fishes. Changes to jaw development can alter feeding mechanics in ways that affect an organism’s ability to acquire and/or process food items. Therefore, derived patterns of jaw morphogenesis are frequently associated with evolutionary shifts in tropic ecology. Changes in thyroid hormone (TH) signaling can have strong developmental effects on vertebrate anatomy, particularly the shape of the lower jaws. Zebrafish mutants (opallusb1071) are hyperthyroid and typically undergo abnormal mandible elongation. However, opallus do not always develop the expected elongated lower jaws; a short-jawed phenotypic variant of opallus exists. This project aims to investigate both the developmental controls of mandibular elongation in zebrafish and how mandible elongation could be ecologically advantageous. To do this, we have 1) estimated the heritability of the longjaw phenotype; 2) tested TH levels to determine if opallus are significantly hyperthyroid compared to wildtype fish; and 3) used phylogenetic-ANOVA and Phylogenetic Generalized Least Squares modeling to identify how changes in mandible length has impacted feeding mechanics in danionins. This study serves as a foundation to understanding the ecological advantages and developmental controls of mandible length in the zebrafish and other danionine fishes.
Document Type
Event
Start Date
May 2022
End Date
May 2022
Location
Carver Gym (Bellingham, Wash.)
Department
CSE - Biology
Genre/Form
student projects; posters
Type
Image
Rights
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this document for commercial purposes, or for financial gain, shall not be allowed without the author’s written permission.
Language
English
Format
application/pdf
The Heritability, Developmental Determination, and Evolutionary Significance of Mandible Length in the Zebrafish (Danio rerio) and other Danionine Fishes
Carver Gym (Bellingham, Wash.)
Jaw shape plays a significant role in determining feeding niche in fishes. Changes to jaw development can alter feeding mechanics in ways that affect an organism’s ability to acquire and/or process food items. Therefore, derived patterns of jaw morphogenesis are frequently associated with evolutionary shifts in tropic ecology. Changes in thyroid hormone (TH) signaling can have strong developmental effects on vertebrate anatomy, particularly the shape of the lower jaws. Zebrafish mutants (opallusb1071) are hyperthyroid and typically undergo abnormal mandible elongation. However, opallus do not always develop the expected elongated lower jaws; a short-jawed phenotypic variant of opallus exists. This project aims to investigate both the developmental controls of mandibular elongation in zebrafish and how mandible elongation could be ecologically advantageous. To do this, we have 1) estimated the heritability of the longjaw phenotype; 2) tested TH levels to determine if opallus are significantly hyperthyroid compared to wildtype fish; and 3) used phylogenetic-ANOVA and Phylogenetic Generalized Least Squares modeling to identify how changes in mandible length has impacted feeding mechanics in danionins. This study serves as a foundation to understanding the ecological advantages and developmental controls of mandible length in the zebrafish and other danionine fishes.