Date of Award


Document Type

Masters Thesis

Degree Name

M. S.

Organizational Unit

College of Natual Science and Mathematics, Physics and Astronomy

First Advisor

Dinah Loerke

Second Advisor

Todd Blankenship

Third Advisor

Michelle Knowles


Watershed segmentation, Drosophila


The watershed segmentation is an algorithm used to systematically track cell intercalary behaviors during germ band extension of the Drosophila embryo. Neighboring cells share a contracting vertical interface, called a T1, which continues contracting to a single point, a T2, and extending in the horizontal direction to create what is called a T3 interface (Fig. 1). Additionally, higher order vertices called rosettes occur when five or more cells meet at a common vertex. Simulated T2 events demonstrate that cell angle and not noise level in the image contributes to the incorrect detection of artifactual T1s in more acute angled cells and T3s for obtuse angled cells. Short T1 simulations show a systematic overestimation of T1 lengths detected by the watershed segmentation. Order three vertex simulations show central vertex displacement is biased toward the smallest angled cells. Rosette simulations of order 5 to 11 provide a working definition of rosettes in the context of the watershed segmentation in terms of short interface frequency, length, and radius of artifactual vertices.

Publication Statement

Copyright is held by the author. User is responsible for all copyright compliance.

Rights Holder

Emily Jo Armitage


Received from ProQuest

File Format




File Size

66 p.