There's a lot of animals in the open ocean - most of them that make light. And we have a pretty good idea, for most of them, why. They use it for finding food, for attracting mates, for defending against predators. But when you get down to the bottom of the ocean, that's where things get really strange.
Giant squid aren't rare. Based on the number of beaks that have been found in the stomachs of sperm whales, it's thought that there are actually millions of them in the ocean, and yet, we haven't seen them.
If we are to be good stewards of the ocean, we need to understand what lives there and how the animals interact with each other and with their environment, which means we need to be constantly seeking new and improved methods for exploration and observation.
