Evolution by Random Processes

Question 1

Mutation:

Answer 1

• Occurs randomly

- Can add to genetic variation of a population

Question 2

Genetic Drift:

Answer 2

Change in the genetic composition of a population over time as a result of random mating

Question 3

Bottleneck Effect:

Answer 3

A reduction in the genetic diversity of a population caused by a reduction in its size

Question 4

Founder Effect:

Answer 4

When a small # of colonizing individuals creates a change in population

Question 5

Allopatric Speciation:

Answer 5

When new species are created by geographic or reproductive isolation

Question 6

Sympatric Speciation:

Answer 6

The process through which new species evolve from a single ancestral species while living in the same geographic region

Question 7

Realized Niche:

Answer 7

The range of abiotic & biotic conditions under which a species lives

Question 8

What does a realized niche determine?

Answer 8

The species distribution, or areas of the world where it lives

Question 9

Niche Generalist:

Answer 9

Species that live under a wide range of conditions

Question 10

Niche Specialist:

Answer 10

Species that live only in specific habitats

Question 11

Fossils:

Answer 11

Remains of organisms that have been preserved in rock

Question 12

Range of Tolerance:

Answer 12

The limit to the abiotic conditions a species can tolerate

Question 13

Fundamental Niche:

Answer 13

The ideal conditions for a species

Question 14

The Five Global Mass Extinctions:

Answer 14

When large numbers of species went extinct over a relatively short period of time.

Question 15

The Sixth Mass Extinction:

Answer 15

• Scientists feel we are currently in our Sixth Mass Extinction occurring over the past 2 decades
• Scientists agree this one is caused by humans