Manic crabs caught on underwater camera

Andy Burnell, an avid Australian fisherman, had always wondered what the crabs were up to whilst he was out on his kayak. So he tied a camera to his crab net and started recording. The footage not only surprised him, but many other Adelaide locals, who never expected so much was happening just under the surface.

Class discussion: What did you think of the video? Water covers most of our planet. How much do we know about what is going on under the sea? How many ocean species are threatened with extinction? Could the loss of ocean creatures impact our chances of survival? Over the millennia, sea levels have changed drastically. What causes the world ocean to grow or shrink? What is it doing now?