Geo2: Chapter 8

• 1. Wind
• Ex. Anemophores
• 2. Water
• Ex.Hydrophores
• 3. Animals
• Ex. Zoochores

• 1. Seed predation
• -Ex. Acorn woodpecker

ability to successfully expand onto a new area

• the annual movement of an organism from region to another
• Ex. Salmon migration 

the episodic explosion in the population size and geographic range of insects or animals

• 1. Exponential growth 
• -an unrestricted increase in population size
• 2. Logistic growth
• -the S-shaped growth in an environment which there is a limitation to the population size

the number of individuals of a species that a given area can support

gradual, slow penetration 

long distance expansion 

geographical feature that blocks dispersal/colonization 

geographical feature that promotes dispersal/colonization 

-allowed human and animal migration from Asia to North America

• movement of terrestrial fauna after formation of the Isthmus of Panama 
• -from North America to South American and reverse

colonization of remote islands

• -non-native species
• -introduced voluntarily or involuntary by the people
• -Ex. Asian longhorned beetles destroy mature trees

• -species that is not native and causes disruption 
• Ex. Cane Toad(South America) introduced to Hawaii

• Ex. Nile(Africa) perch introduced to lake Victoria
• Ex. zebra mussels

allowed zebra mussels to enter the Great Lakes from the ballast water of ships

• 1. Emergent Layer
• 2. Canopy
• 3. Under Store
• 4. Shrub layer
• 5. Forest floor