Exam 2

Question 1

What is gene flow? (Hint: What’s a synonym?)

Answer 1

Movement of an individual or genetic material from one population to another (aka Migration) - Important source of genetic variation

Question 1

What is genetic drift?

Answer 1

A mechanism of evolution in which things evolve by chance

Question 2

What are some examples of gene flow?

Answer 2

Pollen and people traveling

Question 3

What is natural selection?

Answer 3

The first proposed mechanism for evolution- dependent on environment and existing heritable variation

Question 4

How was natural selection discovered?

Answer 4

Discovered by Charles Darwin on the Galapagos Islands - high level of endemism

Question 5

How does natural selection work?

Answer 5

Limited resources —> organisms w/heritable traits favoring survival and reproduction tend to leave more offspring–> traits increase –> population becomes more adapted to environment overtime

Question 6

What is evolutionary fitness?

Answer 6

How good a genotype is at leaving offspring in the next generation relative to others (success @ surviving and reproducing)

Question 7

How does evolutionary fitness affect evolution?

Answer 7

Organisms with highly favored heritable traits pass their genes onto the next generation

Question 8

What are adaptations?

Answer 8

Features that arose and were favored by natural selection based on function that help organisms survive and reproduce

Question 9

Does a trait always stay adaptive?

Answer 9

No, things like vestigial structures show that not all past traits are adaptive now

Question 10

What kind of adaptations exist?

Answer 10

Behavioral - allows for better evasion of predators

Anatomical - feature giving organisms access to valuable new resources

Protein - functioning better @ body temp (?)

Question 11

What is “Survival of the Fit Enough” more accurate than “Survival of the fittest”?

Answer 11

Survival of the fittest implies biggest and toughest survive to pass genes while survival of fit enough implies that organisms that live long enough to pass on genes

Question 12

What is sexual selection?

Answer 12

A mechanism for evolution that takes two forms

Intersexual selection (mate chooses mate of other sex)

Intrasexual (mates compete w/ members of same-sex or opposite sex)

Question 13

How does sexual selection influence evolution?

Answer 13

Sexual dimorphism - differences/clear distinction between sexes of a species

Question 14

What is artificial selection?

Answer 14

A mechanism of evolution where people select organisms to reproduce

Question 15

How have humans leveraged inheritance long before the mechanisms of evolution were discovered?

Answer 15

Farmers and breeders allow only plants and animals with desirable traits to reproduce (think about fruit in grocery store)

Question 16

What is coevolution?

Answer 16

two or more species reciprocally affect each other’s evolution/have close ecological relations (ex, prey, and predator)

Question 17

Why ?

Answer 17

answer later

Question 18

When do we see organisms coevolve?

Answer 18

Two main examples

Competition (through share similar niches)

Mutualism (helping one another like bees and flower)

Question 19

How are organisms, population, and ecosystems related?

Answer 19

Organisms tend to live in populations with in ecosystems

Question 20

What are biotic factors in an ecosystem?

Answer 20

Living factors (fungi, plants, animals, bacteria)

Question 21

What are abiotic factors in an ecosystem?

Answer 21

Non-living factors (air, minerals, water, sunlight)

Question 22

How do biotic and abiotic factors influence each other?

Answer 22

They act as selective pressures and drive evolution (check)

Question 23

What are selective pressures?

Answer 23

Evolutionary forces that favor a certain phenotype in a certain environment

Question 24

How do selective pressures affect the evolution of populations?

Answer 24

They drive evolution through natural selection

Question 25

What is a niche?

Answer 25

A specific role that a species plays

Question 26

How do niches relate to evolution?

Answer 26

Niches are developed through evolution based on a species phenotype, type of food it eats, relations w/other species, where it lives, reproduces