Lizard Eggshell Research

Challenge

Unlike chicken eggshells, lizard eggshells are soft and stretchy. As a result, lizard eggshells start small when laid, but expand over time to make room for the growing embryo. The material properties that allow this were unknown.

Solution

We performed mechanical testing on the eggshells to discern whether their stress-strain curve was more similar to biological material, crystalline material, or some other material. We also took scanning electron microscope (SEM) pictures to see the internal structure of the egg. As a result, we learned that the eggs have outside crystalline layers surrounding a fibrous, biological inner layer.

Role

I led mechanical testing of the eggshells and assisted with SEM sample preparation.

Tools

Dynamic Mechanical Analysis, MATLAB