Intro to Evolution
Evolution & HW
Speciation
Terms
RANDOM
100

True/False: Evolution only occurs slowly and gradually

FALSE

Small population size, short generation time, and big shifts in the environment can lead to rapid evolution 

100

What is the definition of evolution?

Change in gene frequencies over time

100

Reproductive isolation, in the absence of geographical isolation, can result in what?

Sympatric Speciation 

100
What is the ultimate source of variation?

Mutations

100

Evolution occurs at the ___________ level and natural selection occurs at the __________ level.

Evolution = Population Level

Natural Selection = Individual Level

200

T/F 

Adaptations are changes to the genes that increase survivorship and arise through demand

False. They do not arise through demand.

200

True/False: The bottleneck effect takes place when a few individuals become isolated from a larger population.

False

Founder Effect = a few individuals become ISOLATED from a larger population

Bottleneck Effect = a sudden REDUCTION in population size due to environmental change 

200

What is the key evolutionary unit?

Species

200

What type of isolation is the most important for the biological species concept?

Reproductive Isolation

200

Geographical isolation is generally (intrinsic/extrinsic).

Extrinsic

Occurs outside of the population/organism

300

What are the 2 requirements a trait must have in order to be able to evolve?

1. The trait must be heritable

2. There must be variation in the traits

300

Draw a graph for each of the 3 patterns of natural selection (write which is which).

300

What types of speciation takes place when a portion of the population is separated?

Peripatric Speciation 

300

What type of isolation occurs when species occupy different habitats.

Ecological Isolation 

300

Allopatric is caused by ______ factors

Extrinsic. Think of a barrier arising and permanently separating two populations. 

400

Define a scientific theory.

A hypothesis with LOTS of support

400

What is the difference between "p," "p^2," & "2pq"?

p = frequency of the dominant ALLELE in the population

p^2 = percentage of homozygous dominant INDIVIDUALS 

2pq = percentage of heterozygous INDIVIDUALS

400

Define divergent evolution.

Organisms with a recent common ancestor evolve to look different due to different environmental pressures.

400

One of the driving forces of  ___________ __________ is habitat heterogeneity.

Adaptive Radiation 
400

What is artificial selection? 

Manually controlling which traits are selected for and passed down to future generations 

500

List 1 of Darwin's observations and 1 of Darwin's inferences. (Hint: you learned 2 of each)

Observations

1. Individuals in a population vary in their heritable characteristics

2. Organisms produce more offspring than the environment can support

Inferences

1. Individuals that are well suited to their environment tend to leave more offspring than other individuals

2. Over time, favorable traits accumulate in the population 

500

List the 5 assumptions of Hardy Weinberg.

1. No natural selection

2. Random mating

3. No mutations

4. No migration

5. Infinite population 

500

List the 5 types of pre-zygotic isolation.

1. Ecological

2. Temporal

3. Behavioral

4. Mechanical

5. Gametic

500

List the 5 mechanisms of evolution.

1. Natural Selection

2. Sexual Selection

3. Mutations

4. Genetic Drift

5. Gene Flow

500

What is convergent evolution?

When unrelated/distantly related species begin to adapt for the similar traits over time.