From the Sun, Through an Ecosystem, Into Heat Energy Flow From the Sun, Through an Ecosystem, Into Heat

Autotrophs / Producers Auto = Self-made example: Automatic, Automobile Troph = Eater / Food Example: trophy (prizes in competitions used to be food!) So, AUTOTROPHS make their own food. They produce their own food. How? Photosynthesis!!!!

Heterotrophs / Consumers Hetero = different Troph = food Heterotrophs CANNOT make their own food, so they must eat other organism. They consume other animals. Heterotrophs are ALL organisms that eat other organisms They are herbivores, carnivores, omnivores, and detrivores. ALL of these animals cannot make their own food, and must eat other organisms (including plants) FOR food!

Decomposers DECOMPOSERS are heterotrophs that eat dead things and in the process return nutrients to the soil. DECOMPOSERS are always DETRIVORES Detrivore specifies that they eat dead things Decomposer specifies that they break down dead things and return nutrients to the soil What are some examples of DECOMPOSERS?

DECOMPOSERS Bacteria Fungi Flies Maggots Hyenas Dung Beetles Worms Mold

Primary, Secondary, Tertiary Primary Consumers eat Autotrophs (plants) Secondary Consumers eat Primary Consumers Tertiary Consumers eat Secondary Consumers

Pop Questions Are all consumers meat-eaters? NO! Herbivores are consumers too Are carnivores ever primary consumers? NO! But, omnivores can be Are herbivores always primary consumers? YES!

Trophic Levels Each step in the chain represents a TROPHIC LEVEL A trophic level is an feeding step in the passage of energy and materials through an ecosystem

Energy Flow Energy enters the ecosystem as Sunlight Sunlight is the One + Only + Ultimate energy source It is turned into food by autotroph (plants) However, plants only capture 1% of total sun / energy Plants use this energy to grow, to reproduce, to move (a little), and to keep themselves alive Overall, plants use 90% of energy this way! So, only 10% of energy is passed on to the next trophic level (whatever eats the plant)

10% Rule At every level, 90% of the energy received from food is used to keep the organism alive. For example, a zebra who eats grass only gets 10% of the energy from grass that the grass got from the sun. Then, the lion who eat the zebra only gets 10% of the energy from the zebra that the zebra got from the grass. This makes sense! THE ZEBRA USES ENERGY RUNNING AWAY FROM THE LION!!

Energy Pyramid

Pop Question!

The same holds true with Biomass Biomass: Total amount of living tissue within a given trophic level (I am ___ lbs of human biomass) Just like an energy pyramid, BIOMASS decreases as you go up trophic levels. And, the 10% Rule applies! Energy is mass!

So, how much grass does it take you to survive? Meat Eater: Vegetarian: Human  Cow  Grass  Sun 150lbs x 10 (cow) x 10 (grass) 15,000 lbs Human  Vegetables  Sun 150lbs x 10 (veggies) 1500 lbs It’s better for the earth to be a vegetarian. Except… You may not be getting enough PROTEIN!

Ok, let’s see how we’re doing First, put a P (producer) or a C (consumer) next to the animals Now, put a O (omnivore), H (herbivore), or C (carnivore) next to the animals too. Now draw an energy pyramid (up to Tertiary Consumer) using any of those animals.