Today, my friend Erin and I saw at least fifty (yes, this isn’t a hyperbole) sea lions in the San Francisco harbor. Though they are an attraction of the aquarium, the public can view them for free. Many were resting on the wooden pallets, while a few were play fighting or wiggling around.
The sight of these sea lions in their respective resting stupors reminded me of two featured talks on fur seal and walrus sleep at the last two SLEEP meetings. In 2007, a research group from Russia discovered that walrus not only enter REM sleep, but reduce the risk of drowning during REM-induced muscle atonia by means of digging their tusks into the ice! Though one member in the audience was vocally baffled by the fact that this study was fundable (no joke), I thought it was one of the most interesting talks of the meeting. This year, another, but unrelated group, presented characteristics of NREM and REM sleep in the fur seal.
I do not believe many of today’s sea lions were in REM sleep when we saw them, but I ask, what unique and species-specific behaviors do these sea lions exhibit during respective stages of NREM and REM sleep?