Date of Award

Spring 2008

Document Type

Restricted Thesis

Terms of Use

© 2008 Yusha Hu. All rights reserved. Access to this work is restricted to users within the Swarthmore College network and may only be used for non-commercial, educational, and research purposes. Sharing with users outside of the Swarthmore College network is expressly prohibited. For all other uses, including reproduction and distribution, please contact the copyright holder.

Degree Name

Bachelor of Arts


Biology Department

First Advisor

Scott F. Gilbert


Previous studies from this laboratory suggest that the plastron of the turtle is formed from trunk neural crest (TNC) cells that regain their osteogenic potential through delayed migration from the neural tube. This hypothesis is controversial because TNC cells are not typically known to have skeletogenic potential. In order to confirm the emergence and migration of this cell population, DiI lipophilic marker was injected into the lumen of the neural tube to unambiguously label cells with endfeet in contact with the lumen. Results show the clear emergence and ventral migration of a labeled population of cells from the dorsal neural tube in late-stage turtle embryos, beyond known periods of TNC cell migration. However, control experiments with late-stage chicken embryos did not rule out the possibility of other explanations for the observed migration in late-stage turtle embryos. These results add to a growing body of evidence that a novel late-migrating population of TNC cells form the bones of the plastron.