During the course of the past thirty years, the study of model organisms has become more significant in the study of embryological development. A model organism is a species that is easy to cultivate and monitor in a laboratory environment and is used to represent broad groups of organisms. Examples of successful and important model organisms include the Ascidia, Zebrafish, and Medeka species. Through intense researching of these organisms, scientists have been able to gain valuable insight into the developmental processes of many complex vertebrates, including humans.

Model organisms are used to study embryonic development for several reasons. These organisms have shared characteristics including short life spans and generation intervals, rapid development, and easily distinguished embryos, which make them ideal experimental targets. Through the mapping of developmental processes and similarities between the model organisms and other major vertebrate groups have been discovered, the model organisms serve to represent...