I'm a little late to this, but I couldn't resist: Wired Science reported yesterday that researchers at New York University are studying Mexican cavefish for clues about human sleep disorders. Rachel Zurer writes:
By breeding the fish with their sighted counterparts, scientists determined that the difference in their sleep patterns is genetic. The discovery may help identify genes and pathways involved in insomnia and other sleep disorders in humans.
...To confirm that the differences in sleep habits they observed were genetic, the researchers bred the various cavefish populations with the surface fish. The offspring slept like cavefish, indicating a dominant gene for sleeplessness. A second generation, bred by mating that first hybrid generation, showed sleep behaviors in between the two populations. The researchers concluded that a few specific genes must be responsible for the sleep change.
The research is interesting - and it isn't the first time fish have been used to study sleep. In another example, Stanford researchers studied Zebrafish to understand how how sleep and the body's circadian clock affect the number of neuron-to-neuron connections in a particular region of the brain.