Potomac Valley Aquarium Society

Meeting Notes

August, 2008

Dr. Ray Engeszer is a professor at U. of Md. and GWU. He was an electrician for over eleven years, before choosing to go back to school to get an advanced degree. He studied zebra fish for his PhD, to determine whether shoaling behavior is learned or is genetic.

Dr. Engeszer talked about fish behavior using the common zebra fish as a specimen because so much is known about its DNA, and it is a very robust fish which is quick to mature, making it ideal for scientific study. He reports that a stripe-less or pearlescent zebra fish is created by a gene mutation, and can be easily created in the lab. Each fish is identical in DNA to its siblings with stripes with the exception being that mutated gene.

With a series of experiments, he showed that a fish learns to shoal. He showed that a young fish will shoal with whichever group it grows up, rather than whether or not it has stripes. An interesting aside, is that schooling is a defensive behavior, and the more common shoaling is seen to be a loose group of fish.

It was a very entertaining presentation with anecdotal stories of different fish behaviors, pictures of his travels to India to collect zebra fish, and the scientist's viewpoint in studying zebra fish.

Recording Secretary, Mark Harnet