Ecology is the scientific study of interactions between organisms and their environments, focusing on energy transfer. There are three main types of feeding relationships: producer-consumer, predator-prey, and parasite-host. Producers, like plants, make their own food through photosynthesis. Consumers eat other organisms for energy and include both predators that hunt prey and animals that eat plants or other animals. A food chain shows what organisms eat in a linear feeding order starting with producers, while a food web depicts the complex and interconnected feeding relationships in an ecosystem.

1. Ecology

2. What is ecology?
Ecology- the scientific study of
interactions between organisms
and their
environments, focusing on
energy transfer
• It is a science of relationships.

3. Feeding Relationships
• There are 3 main types of feeding
relationships
1. Producer- Consumer
2. Predator- Prey
3. Parasite- Host

4. Producers
• Plants are living organisms. They need
nourishment to survive.
• But…
• Plants do not eat other plants or
animals.
• Plants are called producers, because
they make their own food inside
themselves.

5. Consumers
• “Consume” means “eat”.
• Animals are consumers because they
“eat” (consume) food provided by plants
or other animals.

6. Predator
A predator eats other animals.
Cats eat fish. So do bears!

7. Predator
• The cat is a predator, because it eats
other animals.
• The bear is a predator, because it
eats other animals.
• People are predators too!

8. Prey
Any animal which is hunted and killed by
another animal for food is prey.
Predator
Prey

9. Match the predator to its
prey.

10. Parasite to Host Relationship
• One organism, usually physically smaller of
the two (the parasite) benefits and the other
(the host) is harmed
• Parasites examples: Ticks, Fleas, Mosquitos
• Hosts examples: Deer, Dogs, Humans

11. In order to live animals need energy.
Some animals get the energy they need to live from
eating plants and other vegetation.
Some animals get their energy from eating other
animals.
Some animals eat both plants and other animals.
All energy begins with the sun.

12. Food Chains
A food chain shows what is eaten.
The fly is eaten by the thrush.

13. Food Chains
A food chain shows what is eaten.
The lettuce is eaten by the
rabbit.

14. Food chains always start
with a plant.
The lettuce is eaten by the slug, the slug is eaten by the
bird.

15. Food Chains - a Reminder
• A food chain shows which animals eat
other animals or plants.
• Plants don’t eat things.
• A food chain starts with what gets
eaten and the arrows point towards
what does the eating.
• Food chains only go in one direction.

16. The top of the food chain.
Some animals are said to be at the top of the
food chain. This is because they are not hunted
by other animals. They are called APEX
predators.
No other animal hunts the
lion. The lion is at the top of
the food chain. Can you think
why?

17. Food Webs
• In the wild, animals may eat more than
one thing, so they belong to more than
one food chain.
• To get the food they need, small
herbivores may eat lots of different
plants, and carnivores may eat many
different animals.