What’s the deal with the styrofoam heads?
The styrofoam heads are something we do for fun on the research cruises when all of the work is done. We buy them from local stores in La Paz or a wholesaler in the US. They are the same size as a normal human head when we get them. We draw on them with Sharpies and then tie them in a dive bag on the side of the ROV so that when the ROV is at depth (10 meters of water depth = 1 atmosphere of pressure = 15 pounds per square inch) of say, 3000 meters, the head will be compressed to about 1/10 of its size!
(Thanks to investigator Annie Nocklis for bringing this to our attention.)