1. Chapter 10 Lesson 2 Relationships Within Ecosystems
Ms. Amanda and Ms. Diana

2. Niches
Niche – is the way a species interacts with abiotic and biotic factors to obtain food, find shelter, and fulfill other needs.

3. Competition
Competition – the demand for resources, such as food, water, and shelter, in short supply in a community.
Competition can take place among members of a population or between two populations of different species.
Competition limits population size.

4. Overpopulation
Overpopulation – when a population becomes so large that it causes damage to the environment.
Examples:
1. When too many deer live in an ecosystem, they eat all the plants and that reduces habitats for other animals.
2. Deers move into areas where they are forced to live too close together. Disease can spread easily within populations when this happens.
Overpopulation is temporary because when resources run out, animals will move somewhere else, starve, or die from diseases.
So the population decreases, then it gives the environment some time to return back to normal.

5. Competing with Humans
Humans need the same biotic and abiotic factors as other organisms. Humans need food, living space, and water.
To get their needs, humans do many different things:
Plant food crops
Build roads and buildings
Use water from lakes for drinking
These actions put humans in competition with other species for the same resources.

6. Predation
Predation – the act of one organism, a predator, feeding on another organism, its prey. (predator – organism that hunts and kills other organisms for food)
Predators help control the size of prey populations.

7. Symbiosis
Symbiosis – a close, long-term relationship between two species that usually involves an exchange of food or energy.
There are 3 types of Symbiosis:
1. Mutualism – relationship in which both organisms benefit.
2. Commensalism – relationship in which one organism benefits but the other doesn’t benefit and is not harmed.
3. Parasitism – relationship in which one organism benefits while the other is harmed.

8. Types of Symbiosis