John P. Trinkaus spent a significant part of his career and summers at MBL studying development in Fundulus heteroclitus, a species of teleost fish. The primary focus of his studies in Fundulus was the locomotion and migration of cells during gastrulation, the embryonic event during which the three foundational tissue types (germ layers) are established.
Trinkaus visualized the movements of cells during gastrulation largely by producing numerous films of the process. Using time-lapse microcinematography, he could speed up development to see every step in a matter of minutes. The film strips also provided Trinkaus with series of snapshots that he could print and closely analyze. By identifying the same cells in sequential images and marking them, he could determine how individual cells were moving or changing shape as the whole tissue advanced.
Trinkaus used these film stills in many of his publications to demonstrate cellular behaviors during Fundulus gastrulation. Trinkaus often included drawings or diagrams along his micrographs to more clearly illustrate changes in shape or mechanisms of locomotion. Many of these research films were also projected during community movie nights at the MBL during the summers.