We often hear about living things being endangered. Sometimes the plant or animal is becoming extinct, or dying out. Often we have never heard of the animal or plant that is in danger. Does it matter if it dies out? The story of the sea otter shows what can happen if a species disappears from an area. In the past, sea otters lived all along the west coast of North America. Sea otters often us…
Food chains and food webs are about energy. All living things need energy. Without it, they cannot grow, or move, or produce young. Animals need energy to grow and reproduce. Wolf spiders produce many young, which they carry on their backs. As we will see in the next chapter, plants get their energy from the Sun. They use light energy to make their own food. Animals cannot make their own f…
A food chain or web shows how energy moves from one group of living things to another. Think of a mouse. A mouse gets the energy it needs from eating grass and seeds. If the mouse is eaten by a snake, its energy moves up the food chain to the snake. The starting points in any food chain or web are the living things that make their own food. These are called producers. On land, green plants are th…
Any living thing that needs to eat food is a consumer. All animals are consumers. So are many microscopic creatures. Many consumers eat plants or parts of plants. They are called primary consumers. They are also known as herbivores. Animals such as cows, horses, elephants, deer, and rabbits are grazers. They eat grass and the leaves from bushes and trees. Hummingbirds need lots of energy to k…
When we make and eat a meal, there is nearly always waste. When we go to the toilet, we rid our bodies of waste. This waste comes from the food we have eaten. Imagine none of this waste was cleared up. It would soon cover the Earth. Decomposers are nature's way of removing and recycling waste food. The mold on this orange is a kind of fungus, called penicillium. The fungus grows by dra…
We have seen how different plants and animals are connected to each other through food chains. But very few things are part of a single food chain. Let's look again at the food chain in Chapter 1. This chain connected kelp, sea urchins, and sea otters. Sea urchins eat kelp. But other animals, such as sea snails and crabs, do too. So kelp is part of more than one food chain. At the other e…
Food webs change. They change as the environment changes. Imagine a group of plants dies out. Animals that feed on the plant must find other food to eat. Or maybe a new animal has come into an area. It competes with the animals already living there. These changes often affect the whole food web. Often animals have to survive in difficult conditions. These cattle In Queensland, Australia, are …
algae (AL jee) — most algae are tiny, plant-like living things, seaweeds are also algae caiman (KAY muhn) — a kind of crocodile found in South America caribou (KA ri boo) — a large mammal of the deer family, caribou are related to reindeer decomposers (dee kuhm PO zurs) — living things such as fungi and bacteria that get food by breaking down the remains of plants or a…
Food Chains and Webs. Lewis Parker. Perfection Learning, 2005. Life in a Kelp Forest. Mary Jo Rhodes and David Hall. Children's Press, 2006. The World of Food Chains with Max Axiom, Super Scientist. Liam O'Donnell. Capstone Press, 2007. Who Eats Who in City Habitats? Robert Snedden. North Mankato, Minnesota; Smart Apple Media, 2006. One of a series of books. Others cover food chains…