Yes, I should have backed up what I said about Zebrafish being a genetic model. I realise also we are getting way off the topic, but here's some links if you're interested.
The zebrafish as a model organism has the following advantages:
Its genetics and development have been studied intensively.
It is a vertebrate, so its genome is similar to other vertebrate species including humans.
It is inexpensive
The embryo does not develop hidden inside the mother (as mammalian embryos)
The embyo’s themselves are translucent, allowing visualisation of individual developing cells.
There are stock centers/libraries around the world containing large numbers of some live mutants and frozen sperm of others.
One of many articles explaining the importance of Zebrafish (in pdf).
Websites of two of the stock centers: the Zebrafish international research centre and the Max Planck institute in Germany.