Fish

Author: Huaiyi
Publisher:
Publish Date: 1999-04-01
Features: Most children don't know much about fish because fish live in water, and we don't have many opportunities to observe them. In fact, there are 25,000 known fish species in the world, which is more than the combined total of the other five vertebrate groups (amphibians, reptiles, birds, and mammals). Fish are very useful to humans. Let's learn more about fish. Fish live in water, breathe with gills, and swim around using their fins and tails. Most fish hatch from eggs. Fish have good vision, with nostrils to smell and inner ears to hear, allowing them to sense their surroundings at all times while swimming. Most fish have body colors similar to their environment, which helps them hide from predators. Some fish even have bright, colorful patterns to warn enemies to stay away. Fish move forward by swinging their tails from side to side, and the tail fin is also called the caudal fin. Other fins help keep the body upright, stop movement, and change direction.