20,000 colleagues under the sea economist.com SAILING the seven seas is old hat. The latest trick is to glide them. Sea gliders are small unmanned vessels which are now cruising the briny by the hundred.
Lemon Shark: Can grow to 10 feet long. This stocky, powerful shark is named for its pale yellow-brown to grey skin, which lacks any distinctive markings. This provides perfect camouflage when swimming over the sandy seafloor in its coastal habitat. It has a flattened head with a short, broad snout, and the second dorsal fin is almost as large as the first. The lemon shark is found mainly along the subtropical and tropical parts of the Atlantic and Pacific coasts of North and South America.