Sharks have been around a lot longer than humans. The earliest cartilaginous fishes, descendants of the sharks and rays, were present 375 million years ago. This is long before the arrival of modern man less than a million years ago. Humans, on the other hand, do not have as well-developed senses and a smaller mouth, but have evolved a larger brain and a variety to their behavior that has enabled them to succeed in the modern environment. One cannot say at this point which will outlast the other, humans or sharks, though sharks suffer more from human fishing than humans do from the rare shark attack.
Sharks locate their prey by the low-frequency sounds emitted during swimming and other activities.
In one case, sounds that attracted adult sharks to a speaker were played back to baby sharks just after birth. These sharks were attracted to the sounds without having any prior experience, indicating that this crucial ability is stored within the animal's genetic code. It is possible that sharks remain together in family groups after birth. Fishermen rarely catch white sharks, but when they do the fishermen capture more than one individual, indicating that they may school together. Several small white sharks were recently filmed swimming together off Southern California.