5/11/17

1

UNIT EIGHT: POPULATIONS

Notes Pt. 2: Relationships in Populations

1. Communities

◦ All of the biotic (living) things that live in the same region.A. Niche◦ The role that a particular population serves within the community.

◦ Example: Keystone species - Wolves

B. Habitat◦ The environment that the population lives in.

5/11/17

2

2. Symbiotic Relationships

◦ How two organisms interact with each otherA. Mutualism: Both species benefit◦ Example: Bees & Flowers◦ How?◦ Bee’s get food◦ Plants are pollinated

2. Symbiotic Relationships

B. Commensalism: One species benefits, the other species is unaffected

◦ Example: Remora fish & Sharks◦ How? Remora fish gain protection from the sharks and can

feed off of the remains of meals from larger fish

5/11/17

3

2. Symbiotic Relationships

C. Parasitism: One species benefits at the expense of the other.

◦ Example: Mosquitos◦ How? Mosquitos suck the blood from organisms for food,

depriving the host of it’s nutrients

2. Symbiotic Relationships

D. Predator/Prey: Once species benefits by eating the other

◦ Example: Lion and Zebra◦ How? Lion (predator) catches the zebra (prey) for food for

their herd.

5/11/17

4

2. Symbiotic Relationships

E. Invasive Species: A group of organisms that is moved to another location. The new species competes with native species for resources until one of them wins. No two species can occupy the same niche.

◦ Example: Asian Carp, Sea Lamprey

Your Turn!

◦ Match the organisms to the symbiotic relationship a. Barnacle and whale:◦ Commensalism

b. Termites & Asian Carp◦ Invasive Species

c. Ostrich and gazelle◦ Mutualism

d. Mistletoe and Spruce◦ Parasitism

e. Wolf & Elk◦ Predator and Prey