Food Webs

1
Food Webs and Ecosystems
2
Ecosystems

• All ecosystems contain many food chains.
• Each food chain contains both predators and
  prey.

3
Ecosystems

• An ecosystem is a community of living organisms
  (plants, animals and microbes) in conjunction
  with the nonliving components of their
  environment (things like air, water and mineral
  soil), interacting as a system.

4
Energy to Live

• In order for animals to live they need energy.
• Some animals get the energy they need from eating
  plants and other vegetation.
• Some animals get their energy from eating other
  animals.
• Some animals eat both plants and other animals.

5
Producers

• Nearly all food webs start with a green plant.
• Green plants are called producers because they
  produce their own food.

6
Consumers

• Primary, secondary, tertiary
• Herbivore - plant eater
• Carnivore - meat eater
• Omnivore - mixed plant/animal diet

7
Herbivores

• Animals that eat ONLY plants.
• Herbivores have evolved to eat plants.
• They need a lot of energy to stay alive.
• Many have to eat all day long to get enough
  energy.
• They have specialized teeth and stomachs to
  enable them to get the energy they need from
  plants.

8
Manatee

• A manatee is a mammal that lives in the water.
• They are herbivores.
• They eat 150 pounds of plants each day!
• Manatees live in ocean waters off the coast of
  Florida.

9
Carnivore

• An animal that gets its food from eating other
  animals
• Carnivores have evolved to eat meat.
• They have specialized teeth and stomachs to
  enable them to get the energy they need from the
  bodies of other animals.

10
Omnivore

• Animals that eat both plants and other animals
• Many will eat the eggs of other animals
• Omnivores have teeth and stomachs that enable
  them to eat and digest both plants and meat
  (animals).

11
Omnivore

• Some omnivores are scavengers which means they
  eat dead animals.
• Most will eat plants that produce fruit and
  vegetables and will eat both the fruit and
  vegetables.
• Humans are omnivores

12
Food Webs

• Food webs show what eats what in order to gain
  the energy it needs to live.
• Food webs use arrows to show what eats what.

Eaten by
Eaten by
13

• Food chains that overlap are called FOOD WEBS.

14
Prey

• Animals that are hunted and eaten by other
  animals
• Some prey animals are herbivores.
• Some omnivores and carnivores are also prey to
  other animals.

15
Predators

• Animals that hunt and eat other animals
• Some animals are predators and prey.
• This means they eat some animals but are eaten by
  others.
• The top predator that is prey to no other animal
  is called an apex predator.

16
The Biotic Components of Ecosystems

• Producers(autotrophs)
• - Photosynthesis
• Consumers(heterotrophs)
• -Aerobic respiration
• Decomposers

17
Red-tailed hawk
Producer to primary consumer
Gambel's quail
Primary to secondary consumer
Yucca
Jack rabbit
Collared lizard
Secondary to higher-level consumer
All producers and consumers to decomposers
Fungi
18
Writing Activity

• Write a paragraph describing how a food web
  works. Use the information you have learned in
  this lesson. Be sure to tell about animals that
  are both predators and prey.