Why are zebrafish used in research?

In the early 1970's, a scientist at the University of Oregon by the name of Dr. George Streisinger determined that the zebrafish is a wonderful model for studying vertebrate development and genetics. Since he began using them in his research, zebrafish embryos have become very popular worldwide as a means of understanding how not only fish, but all vertebrates including people, develop from the moment that sperm fertilizes an egg. The eggs are clear and develop outside of the mother's body, allowing scientists to watch a zebrafish egg grow into a newly formed fish under a microscope. The scientists watch while the cells divide and form different parts of the baby fish's body. In the development span of 2-4 days, some form to make the eyes; others, the heart, the liver, the stomach, the skin, the fins, etc. until the fish is complete and ready to begin it's new life. Scientists will occasionally move a cell to another spot to see if it will still go to form the same part of the body ...  more