http://crustacea.nhm.org/~dean2/crab.html
That's.... terrible! You should be ashamed! :P
Umm... Was that relatively huge crab just sucked into a 3mm wide pipe?
Crushed to a fine paste first, then he fit nicely into the tiny little pipe!
Sounds just a bit strange how they manage to keep that pressure so low.....
I doubt it was Zero psi, but probably fairly low..