WE CAN LOOK AT NATURE in the same way that we look at a complicated machine, to see how all the parts fit together. Every living thing has its place in nature, and ecology is the study of how things live in relation to their surroundings. It is a relatively new science and is of great importance today. It helps us understand how plants and animals depend on each other and their surroundings in order to survive. Ecology also helps us work towards saving animals and plants from extinction and solving the problems caused by pollution. Plants and animals can be divided into different groups, depending on their ecological function. Plants capture the Sun's light energy and use it to produce new growth, so they are called producers; animals consume (eat) plants and other animals, so they are called consumers

KINGFISHER

Some carnivores are called top carnivores because they have almost no predators. Their usual fate is to die of sickness, injury, or old age, at which time they become

food for scavengers. The European kingfisher shown here eats a wide variety of food, including small fish such as minnows and sticklebacks, water snails and beetles, dragonfly larvae, tadpoles, and small frogs. The kingfisher is therefore at the top of a complex food web

ECOSYSTEM

A community and its surroundings, including the soil, air, climate, and the other communities around it, make up an ecosystem. The Earth can be seen as one gant ecosystem spinning through space. It recyc its raw materials, such as ves and other plant mer, and is powered by energy from the Sun

DETRITIVORE

Certain types of worms and snails are called detritivores because they eat detritus, or rotting matter, at the bottom of a pond or river. They help recycle the materials and energy in dead and dying plants and animals.

HABITAT

A habitat is a place where a certain animal or plant usually lives. There are several characteristic habitats, such as oak forests,mangrove swamps, and chalk cliffs. A habitat often has one or a few main plants, such as the pampas grass which grows in the grassland habitats of South America. Certain characteristic animals feed on these plants. Some animals live in only one or two habitats; the desman, for example, is a type of muskrat found only in fast-running mountain streams. Other animals, such as red foxes and brown rats, are able to survive in many different habitats. The coral reef shown here is one of the Earth's richest habitats in terms of species, but the water is poor in nutrients.