Communities!

All around us are organisms (living things) living in communities, e.g. in NZ native bush. Each species has its own population within the community, and a niche where it lives.

Producers – Organisms that make their own food from sunlight energy Examples: plants, trees, moss, algae Consumers – Organisms that eat other organisms (plants or animals) Examples: caterpillars, bugs, birds, dogs, possums, fish, frogs, humans Decomposers – Organisms that break down the bodies of dead organisms and waste Examples: bacteria and fungi

Different types of consumers Carnivores – only eat other animals Herbivores – only eat plants Omnivores – eat plants and animals

Food chains A community contains many food chains which link up to form a food web e.g. grass  sheep  human Each step in the food chain is called a trophic level. It shows “who eats who” Energy flows from the lowest trophic level to the highest trophic level. Energy enters the chain as light and exits as heat. The arrow shows the direction of energy flow Only 10% of energy flows from one level to the next. The other 90% is converted to heat.

Trophic levels grass  grasshopper  birds  cats Grass is the….. Third-order consumer Grass is the….. Consumers can be first order (herbivores), second or third order (omnivores and carnivores), and higher! Grasshopper is the….. Birds are the…. Cats are the…. Second-order consumer First-order consumer Producer

Trophic levels grass  grasshopper  birds  cats Grass is the producer Consumers can be first order (herbivores), second or third order (omnivores and carnivores), and higher! Grasshopper is the first-order consumer Birds are the second-order consumers Cats are the third-order consumers Third-order consumer Second-order consumer First-order consumer Producer

T6 Carnivores (fourth-order consumers Seals T5 Carnivores (third-order consumers) Sperm whales Sea birds Penguins T4 Omnivores and Carnivores (second-order consumers) Baleen whales Squid Fish T3 Omnivores (second-order consumers) Krill shrimp T2 Herbivores (first-order consumers) Animal plankton Plant plankton T1 Producers T=Trophic Level