bottom-dwelling rays, bony fishes, crustaceans and octopuses
to 12 feet (3.7 m) and 189 pounds (85.5 kg)
bull, tiger, blue, and oceanic white-tip sharks; Family: Carcharhinidae (requiem sharks)
circumtropical, usually around oceanic islands
Sharks come in many different shapes and sizes, but people are most familiar with the classic look of a Galapagos shark. Its body is solid, large and torpedo shaped—an efficient form for swimming. Dark gray above and lighter below, the Galapagos shark has no distinctive markings except for a ridge that runs between its dorsal (back) fins. If threatened by a predator or competitor, the shark arches its back, lowers its pectoral (side) fins and swims in figure-eight loops. If the intruder doesn't heed this display, the Galapagos shark will chase and attack the intruder. Although Galapagos sharks are considered dangerous, they rarely attack humans.
Sharks are often misunderstood; they're not maniacal eating machines, eager to devour anything or everything in their path. Only about 30 of the approximately 501 species of sharks are dangerous, and even these rarely attack humans. People, however, are responsible for the death of 11,400 sharks every hour, every day. Since sharks grow slowly, breed late in life and generally bear few young, the populations of many species of sharks are declining dramatically. Without more regulations, many species will become extinct.
This shark bears live young. The embryos receive nourishment from a placentalike attachment to the mother's uterine wall.
A shark's nose is superbly sensitive to some odors. It can detect blood in a concentration of only one part per million—the same as one teaspoon of blood in an average-size swimming pool.
Galapagos sharks are curious; they often gather around and bump into boats, oars, divers or anything else that seems to take their fancy.
To rid its stomach of an indigestible object, a shark pushes its stomach out through its mouth, expels the object and then pulls its stomach back into its proper place.
The man who first identified this shark named it after the Galapagos Islands, where he observed the sharks swimming in offshore waters.