How Organisms Interact Topic #4

Two Parts To Ecosystems There are two parts to every ecosystem There are two parts to every ecosystem 1) Biotic – living parts of the ecosystem – humans, bacteria, insects, plants, etc 1) Biotic – living parts of the ecosystem – humans, bacteria, insects, plants, etc 2) Abiotic – nonliving parts of the ecosystem – air, water, sun, rocks, soil (though soil is a mix of biotic and abiotic components) 2) Abiotic – nonliving parts of the ecosystem – air, water, sun, rocks, soil (though soil is a mix of biotic and abiotic components)

Niche A niche is an organisms role in the ecosystem. A niche is an organisms role in the ecosystem. Most organisms fill many roles. Most organisms fill many roles. How can an organism fill many different niches at once? How can an organism fill many different niches at once?

Roles Producers – plants and algae can take the Sun’s energy and nutrients from the soil to grow Producers – plants and algae can take the Sun’s energy and nutrients from the soil to grow Eucalyptus – other examples? Eucalyptus – other examples?

Roles Consumers – eat the food made by the producers Consumers – eat the food made by the producers Consumers can be split into three different groups Consumers can be split into three different groups Koala bear – other examples? Koala bear – other examples?

Roles Herbivores – eat the producers and fill the plant- eating niche Herbivores – eat the producers and fill the plant- eating niche Deer – other examples? Deer – other examples?

Roles Carnivores – animals that eat other consumers and fill the meat-eating niche Carnivores – animals that eat other consumers and fill the meat-eating niche Bengal tiger – other examples? Bengal tiger – other examples?

Roles Omnivores – organisms that eat both consumers and producers (not vegetarians) Omnivores – organisms that eat both consumers and producers (not vegetarians) Grizzly bear – other examples? Grizzly bear – other examples?

Roles Predators and prey – consumers (predators) that kill and eat other animals (prey) Predators and prey – consumers (predators) that kill and eat other animals (prey) Lions and zebras – other examples? Lions and zebras – other examples?

Clean-up Squad They get rid of garbage and waste and break down dead material They get rid of garbage and waste and break down dead material There are two types There are two types 1) Scavengers – organisms that feed on dead or decaying plant of animal matter 1) Scavengers – organisms that feed on dead or decaying plant of animal matter 2) Decomposers – different than scavengers because they don’t actually eat dead material. They grow in or on the dead or waste material, absorbing some of the nutrients into their own cells 2) Decomposers – different than scavengers because they don’t actually eat dead material. They grow in or on the dead or waste material, absorbing some of the nutrients into their own cells

Scavenger - vulture

Decomposer - fungus

Food Chains A food chain is a model that shows how energy stored in food passes from organism to organism A food chain is a model that shows how energy stored in food passes from organism to organism

Food Web A food web is a series of interconnected food chains A food web is a series of interconnected food chains

Pyramid of Numbers Food webs and food chains only show who eats who, but they don’t show how many of one thing that something else eats. Food webs and food chains only show who eats who, but they don’t show how many of one thing that something else eats. Ecologists developed a pyramid of numbers to show this more complex relationship Ecologists developed a pyramid of numbers to show this more complex relationship

Biomass A pyramid of numbers is more detailed, but still doesn’t tell us exactly how much energy is consumed. A pyramid of numbers is more detailed, but still doesn’t tell us exactly how much energy is consumed. We can look at how much each level of the pyramid weighs (how many kgs of grasshoppers are needed to feed a kg of woodpeckers We can look at how much each level of the pyramid weighs (how many kgs of grasshoppers are needed to feed a kg of woodpeckers Biomass is the total mass of all the organisms in an ecosystem Biomass is the total mass of all the organisms in an ecosystem