1. Feeding Relationships
A food chain shows a simple feeding relationship.
Sun →
All food chains start with the sun

2. Feeding Relationships
A food chain shows a simple feeding relationship.
Sun → grass →

3. Feeding Relationships
A food chain shows a simple feeding relationship.
Sun → grass → rabbit →

4. Feeding Relationships
A food chain shows a simple feeding relationship.
Sun → grass → rabbit → fox

5. All food chains start with ENERGY from the sun

6. carbon dioxide from the air
energy from
sunlight
(or light)
water from
the roots
food
transported to the
rest of the plant

7. Photosynthesis carbon dioxide from the air energy from sunlight
(or light)
water from
the roots
food
transported to the
rest of the plant

8. Because plants produce their own food, they are called ‘Producers’

9. The energy is then passed on to animals when they eat the plant.

10. Animals of all shapes…

12. …and sizes!

13. They are called primary consumers
Because these animals are the first to take the food energy from the plants,
They are called primary consumers

14. Some of these primary consumers have predators
Some of these primary consumers have predators. Other animals that feed on them

15. Aphids are eaten by….

16. Ladybirds

17. Animals that eat primary consumers are called secondary consumers

18. But in reality it is more complicated than that
So far this is a straightforward food chain
Sun → aphid → ladybird
But in reality it is more complicated than that

19. This bird eats ladybirds and aphids

20. This bird eats smaller birds, mice, and rabbits

21. Mice and rabbits have other predators

22. What do you think the frog eats?
What will eat the frog?
What do you think the frog eats?

23. Sometimes it’s not entirely clear who eats who!

24. We can show what goes on with the help of a Food Web

25. What would happen if a disease killed off many of the hawks?

26. There will be nothing to eat the snakes, so their numbers will increase.

27. All the frogs get eaten

28. No frogs.
More crickets

29. Most of the cattail gets eaten by the crickets

30. Now the crickets don’t have enough food so their numbers go down

31. ..and so on. Numbers of each species have an effect on the numbers of the other species in the web.

32. B) Humans nearby bring cats into the area.
Use the food web worksheet to predict what might happen in the following situations:
A) There is very little rain and much of the Marsh Grass and Cattail die off.
B) Humans nearby bring cats into the area.
C) The frogs eats some poisoned slugs from a garden