What Eats WhatWhat Eats What

Mrs. Dignan’ss Science ClassMrs. Dignan’ss Science Class

Take a minute to think about the last Take a minute to think about the last meal you ate. What kinds of organisms meal you ate. What kinds of organisms did you eat?did you eat?Plants? – fruits, veggies, chips, bread Plants? – fruits, veggies, chips, bread

productsproductsAnimals? – meat and seafoodAnimals? – meat and seafoodFungi? – mushrooms, bread products, Fungi? – mushrooms, bread products,

some sodassome sodasBacteria? – yogurt, sauerkraut, miso, Bacteria? – yogurt, sauerkraut, miso,

some cheesessome cheeses

OmnivoresOmnivores – Humans are omnivores, – Humans are omnivores, which means we which means we eat both plants and eat both plants and animalsanimals (omni=every, vore=eat) (omni=every, vore=eat)

CarnivoresCarnivores – Some organisms, such – Some organisms, such as cats and dogs, as cats and dogs, only eat other only eat other animals animals (carni=meat)(carni=meat)

HerbivoresHerbivores – Some organisms, such – Some organisms, such as deer and rabbits, as deer and rabbits, only eat plants only eat plants (herbi=plant)(herbi=plant)

DetritovoresDetritovores – Some organisms, such – Some organisms, such as worms and insects, as worms and insects, only eat only eat dead/decaying plants and animals dead/decaying plants and animals (detritus=waste(detritus=waste

Trophic Level - a species’ position on the Trophic Level - a species’ position on the food chain.food chain. What it eats and what eats it. What it eats and what eats it.

(troph=food).(troph=food).There are There are 2 major categories:2 major categories:

Autotrophs Autotrophs produce their own produce their own food food (auto=self)(auto=self)

Heterotrophs Heterotrophs consume food from consume food from other organisms other organisms (hetero=different)(hetero=different)

Trophic levels are further Trophic levels are further divided by the energy divided by the energy

pyramidpyramid

Producers/Primary Producers Producers/Primary Producers – Organisms that – Organisms that produce their own food through photosynthesis produce their own food through photosynthesis (or (or chemosynthesis). Mostly plants and algae, some chemosynthesis). Mostly plants and algae, some bacteria.bacteria.

Primary Consumers Primary Consumers – Organisms that – Organisms that eat producerseat producers. . Mostly herbivores and small omnivores (bugs).Mostly herbivores and small omnivores (bugs).

Secondary Consumers Secondary Consumers – Organisms that – Organisms that eat primary eat primary consumersconsumers. Often small omnivores and carnivores . Often small omnivores and carnivores (birds, rodents, reptiles).(birds, rodents, reptiles).

Tertiary Consumers Tertiary Consumers – Organisms that – Organisms that eat secondary eat secondary consumersconsumers. Often larger carnivores (snakes, wild . Often larger carnivores (snakes, wild cats)cats)

Quaternary Consumers Quaternary Consumers – Organisms – Organisms that eat tertiary that eat tertiary consumersconsumers. . These don’t exist in many food webs These don’t exist in many food webs because there aren’t enough tertiary consumers to because there aren’t enough tertiary consumers to eateat..

Examples of Energy Pyramids Examples of Energy Pyramids in Different Ecosystemsin Different Ecosystems

Examples of Energy Pyramids Examples of Energy Pyramids in Different Ecosystemsin Different Ecosystems

Examples of Different Energy Examples of Different Energy Pyramids in Different Pyramids in Different

EcosystemsEcosystems

Trophic levels tell us about Trophic levels tell us about biomass and energy.biomass and energy.

Biomass – the overall mass of Biomass – the overall mass of a particular group of a particular group of organisms. Depends on both organisms. Depends on both size and populationsize and population

Energy – the amount of Energy – the amount of energy that can be obtained energy that can be obtained by eating a particular by eating a particular organism.organism.

The lowest level of an The lowest level of an ecosystem always contains ecosystem always contains the most biomass and the most biomass and chemical energy.chemical energy.

The highest level always has The highest level always has the least of both.the least of both.

Trophic LevelsTrophic LevelsWhy is this?Why is this?With the exception of deep With the exception of deep

sea vents, all energy on earth sea vents, all energy on earth comes from sunlight.comes from sunlight.

Producers contain the most Producers contain the most energy and mass because energy and mass because they are only 1 step removed they are only 1 step removed from the sun (photosynthesis).from the sun (photosynthesis).

Every time a plant or animal Every time a plant or animal gets eaten some of its gets eaten some of its chemical energy gets wasted chemical energy gets wasted by being converted to heat.by being converted to heat.

Trophic LevelsTrophic Levels Every time a plant Every time a plant

or animal gets or animal gets eaten most of its eaten most of its chemical energy chemical energy gets wasted by gets wasted by being converted to being converted to heat (about 90%).heat (about 90%).

Typically only 10% Typically only 10% of the organism’s of the organism’s energy makes it energy makes it into the next into the next organism.organism.

For example, the average American ate For example, the average American ate about 2,000 lbs of food in 2010. If you were about 2,000 lbs of food in 2010. If you were 200 lbs, that would be 10 times your body 200 lbs, that would be 10 times your body weight.weight.

Most of this is used for energy and heat, Most of this is used for energy and heat, only some is stored as muscle and fat only some is stored as muscle and fat (chemical energy).(chemical energy).