Supplies

Directions

Put a large bowl of water into the freezer to let it get extra cold, and then add ice cubes.
Put a bare hand into the icy water first, to get an idea of how cold the water really is.
Stick your hand inside a Ziploc sandwich bag with a bar of shortening wrapped around it, and then another sandwich bag covering the shortening, to keep it from falling off in the bowl.
Observe how you don't feel the cold-ness of the water when you have the shortening wrapped around the baggy. This is like the insulation arctic animals have that allow them to swim in extra cold waters.