A Dorsal fin is the fin on the back of a fish or whale, porpoise or dolphin. They may be tiny on a goldifsh or may reach 2m high on an orca. Drones are male bees, usually born late in the summer to perform their one function - to mate with new queen bees. The drones then die whilst the new pregnant queens hibernate through the winter. Echolocation is a method of perception used to find out information about the animals surroundings and finding prey.
Echolocation is used by animals such as orca, and bats and is a system similar to submarine sonar.
An orca produces series of very loud clicks and the signal 'hits' objects and bounces back. The orca's brain processes the information and the orca can then 'see' the image. Orca use echolocation to find out about their surroundings, where prey are and where other members of their pod are. Endangered means very few of a species is remaining and the animal is likely to become extinct if nothing is done to protect it and its habitat. The equator is an imaginary line which divides the world around the middle into the Northern Hemisphere and Southern Hemisphere.