Vocabulary: An organism is a living being. You are a living being. A tree is a living being. Most organisms move, eat, breathe, grow, reproduce, and respond to their environment. Not all organisms do all these things. For example, you move but trees cannot move. (S4L1) A community is made by all the different kinds of organisms that live in an area. A community with many different kinds of living organisms is thought to be able to handle changes to the area better. (S4L1a) When people refer to an ecosystem, they talk about the community of living and nonliving things that make up a system in an environment. A pond with plants, fishes, and decomposers in it located on a mountain is an example of an ecosystem. (S4L1) A habitat is the type of area an organism lives in. A habitat has four parts that an organism needs: shelter, water, food, and space. (S4L1c) Producers are organisms that make their own food using sunlight or other chemical processes and that use some of the food they make for their own energy. Plants are producers. (S4L1a) Consumers are organisms that cannot make their own food. They eat producers and other consumers to get energy. Lions, fish, and birds are examples of consumers. (S4L1a) Decomposers are organisms that break down dead and dying organisms. Decomposers get their energy from dead and dying consumers and producers. Examples of decomposers are worms, bacteria, and mushrooms. (S4L1a) Food chains show how different organisms obtain the matter and energy they need. A food chain contains producers, consumers, and decomposers. Grass → rabbit → bear is an example of a food chain. The arrows show the way energy moves. Some of the energy in the grass moves to the rabbit when it eats the grass. Some of the energy in the rabbit moves to the bear when it eats the rabbit. (S4L1b) A food web is all the food chains in an ecosystem. It looks like a web because it shows how all the different organisms in all the combined food chains interact. The only thing in a food web that is not an organism is the Sun. (S4L1b) A predator is an animal that hunts other animals to get its energy. Some predators eat only animals that are alive. Other predators will eat animals that are alive or dead. Predators can be as small as insects. Predators can be as big as whales. (S4L1b) A prey is an animal that is hunted by a predator. Prey can be the smallest insects that are eaten by birds. Prey can also be large animals like elephants. (S4L1b) An herbivore is an animal that eats only plants to get energy. Geese, rabbits, and horses are examples of herbivores. (S4L1b) A carnivore is an animal that eats only other animals to get energy. Spiders, foxes, and mountain lions are examples of carnivores. (S4L1b) An omnivore is an animal that eats plants and animals to get energy. Ants, turtles, and bears are examples of omnivores. (S4L1b) A population is all the organisms of the same species that live in the same area. All the black bears that live in a mountain range are a population. All the raccoons that live in a swamp are a population. (S4L1) Scarcity means that there is less of something. When there isn’t rain for a long time, there is a scarcity of water. (S4L1d) When the population of an area is scarce, it is said to be under-populated. This means that there is less of an organism in an area. An ecosystem that is under-populated with rabbits means the bears will need to find other animals to eat. When an area has too many of one kind of an animal, it is said to be over-populated. The area they live in will not have enough resources for the animals. The animals may need to move to new areas to find food, water, and shelter. (S4L1d) All ecosystems have a balance. This means there are enough resources for the populations of plants and animals that live in the ecosystem. If there is too little of a resource, the plants and animals that need that resource will have problems. The plants in an area that does not get enough water will stop growing. The animals that eat those plants will not have enough food. If there is too much of a resource, there are also problems. If there is too much water, the plants might die. The animals that eat those plants will need to find something else to eat. (S4L1d) An adaptation is a feature of a plant or an animal. Adaptations help animal and plant populations survive in an environment. An adaptation can be a body feature or a way of doing something. Camels are adapted to survive in a desert. They have humps that store water and fat for energy. (S4L2a) Camouflage is an adaptation of plants and animals that increases their chances of survival. Camouflage is the way an animal’s or a plant’s colors can blend in with the environment. Because they can remain undetected, they can survive. A lion is the same color as the grass it hunts in. This makes it easier for the lion to catch prey to eat. A green insect can hide on a green plant. (S4L2a)