8.7: Disruptions To Ecosystems

What is evolution in a population over time?

change

What is an adaptation?

a genetic variation that is favored by selection

What causes adaptations to arise?

mutations which are random and are not directed by specific environmental pressures

What are some results of an increase in the frequency of adaptations?

1) increases biodiversity

2) populations evolve

3) speciation can occur

What is an invasive species?

a species not native to a specific area that harms the community it is introduced to

Why do invasive species often outcompete other native organisms?

they exploit new niches that are free of predators or competitors

How does human activity effect change on local and global levels?

it accelerates change

What are some examples of human impacts on ecosystems?

1) urbanization

2) deforestation

3) erosion

4) extinction

5) pollution

What are some geological or meteorological events that change ecosystems?

1) large habitat disruptions

2) chemical disruptions

How do these events accelerate evolution?

These events can cause:

1) reproductive isolation

2) change in selective advantage

3) new niches