Degree Name

MS (Master of Science)

Program

Biology

Date of Award

8-2018

Committee Chair or Co-Chairs

Dr. Rebecca A. Pyles

Committee Members

Dr. James R. Stewart, Dr. Thomas C. Jones

Abstract

Viviparity has evolved multiple times within squamates. Eggshells are reduced in viviparous forms, which reduces calcium available to embryos during development. This study tested the hypothesis that reduced calcium impacts neonates of viviparous forms. Developmental series from oviparous and viviparous populations of Zootoca vivipara (reproductively bimodal) were cleared & stained to reveal bone development. Photographs (high magnification, calibrated to size) were used to obtain measurements of lengths of the body, humerus, femur, skull and lower jaw, and of ossified portions of limb bones. Percent ossification was scored for targeted skull bones. Results were analyzed using general linear models and revealed no differences in ossification in either limbs or skull. Overall size of oviparous neonates was significantly larger. Findings do not support our hypothesis and indicate that reduction in eggshell calcium in embryos of viviparous populations does not negatively impact limb or skull ossification during development but may influence overall size.

Document Type

Thesis - unrestricted

Copyright

Copyright by the authors.

Included in

Biology Commons

Share

COinS