A typical goldfish has a heart rate of 70 beats per minute. Small, young fish usually have a faster heart beat than old, large fish. A fish's heart rate may slow down in cold water and beat more quickly in warm water. The average resting human heart rate is 60 to 100 beats per minute.
Plankton are the smallest plants and animals living in the ocean.
They drift with the ocean's currents and do not swim. They are the most numerous form of life in the sea and are an important food source for many fishes and other ocean animals. Anchovies, herring, crabs, lobsters and shrimp feed on plankton. So does the largest shark in the ocean, the whale shark. There are more species of bony fishes in the world than all other vertebrates combined.