Chapter 22 - Intro Evolution

Question 1

How did humans get the opsin gene?

Answer 1

through mutation from previous ancestors

Question 2

When was the earth formed?

Answer 2

4.6 bya (billion years ago)

Question 3

When did life form?

Answer 3

~3.8 bya

Question 4

What was early life?

Answer 4

prokaryotic cells

Question 5

Changes in species can lead to?

Answer 5

a formation of new, separate species

Question 6

In the simplest sense, what are species?

Answer 6

different kinds of organisms

Question 7

Individuals of the same _______ share genetic similarity and can (potentially) interbreed

Answer 7

species

Question 8

all the individuals of the same species occupying a specific area at a particular time

Answer 8

population

Question 9

Example of populations

Answer 9

black bears and Joshua Trees

Question 10

What constitutes the Joshua tree species?

Answer 10

all the populations together

Question 11

explanation for a natural phenomenon

Answer 11

theory

Question 12

measure of successful reproduction

Answer 12

fitness

Question 13

All species have descended from other _______. And a single, _______ ancestor lies at base of the evolutionary tree

Answer 13

species; common

Question 14

Natural Selection is what process?

Answer 14

a trait (or character) that confers reproductive advantage to an individual, spreads in a population over successive generations

Question 15

Natural selection required understanding the ________ ________ of populations

Answer 15

biotic potential

Question 16

T/F

Most populations are capable of producing more offspring than can be supported by the environment

Answer 16

true

Question 17

What is exponential growth?

Answer 17

doubling

Question 18

Natural selection requires variation in _______

Answer 18

phenotype

Question 19

Example of phenotypic variation

Answer 19

population of Geospiza fortis, one of Dawrin’s finches

Question 20

Within populations, there is variation between individuals - some of this variation is _______

Answer 20

heritable

Question 21

Overtime, beneficial traits ______ through the population

Answer 21

spread

Question 22

________ is required for natural selection

Answer 22

competition

Question 23

T/F
Genetic traits that provided an advantage will be spread within a population, but those that do not will be lost from the population

Answer 23

True

Question 24

What is evolution?

Answer 24

genetically based change of phenotype in a population over successive generations

Question 25

Species are not fixed entities, but instead are what?

Answer 25

constantly undergoing modification and change

Question 26

Origin of Species | Perceived ___________ as the primary force driving descent with modification

Answer 26

natural selection

Question 27

independently developed theory of evolution

Answer 27

Alfred Russel Wallace

Question 28

Naturalist who believed species were not fixed entities

Answer 28

Jean-Baptiste de Lamarck

Question 29

What are the five agents of evolution?

Answer 29

``` Natural selection Sexual selection Gene flow Genetic drift Mutation ```

Question 30

more offspring are produced then can be supported by the environment

Answer 30

competition

Question 31

a change in DNA sequence (change in nucleotides)

Answer 31

mutation

Question 32

Mutation is an ______ of evolution. How?

Answer 32

agent; Mutations create new alleles

Question 33

the movement of existing alleles from one population to another by dispersal

Answer 33

gene flow

Question 34

Example of gene flow

Answer 34

deer populations

Question 35

chance alteration of allele frequencies in a population

Answer 35

genetic drift

Question 36

Two forms of genetic drift:

Answer 36

Founder effect and Population bottleneck

Question 37

New population is started by a few individuals that are not representative of genetic diversity in the original population

Answer 37

Founder effect

Question 38

What form of genetic drift was seen in red spotted toads?

Answer 38

Founder effect

Question 39

Following population decline, surviving individuals do not represent genetic diversity of the original population

Answer 39

Population bottleneck

Question 40

In population bottleneck, survival is _______

Answer 40

random

Question 41

Example of population bottleneck

Answer 41

elephant seals

Question 42

Differential reproductive success based on differences in the success of obtaining mates

Answer 42

sexual selection

Question 43

Example of sexual selection

Answer 43

Female mate choice within guppies

Question 44

How new species come into being

Answer 44

speciation

Question 45

Occurs when the geographical range of a species is split into discontinuous parts by formation of barriers to gene flow

Answer 45

Allopatric speciation

Question 46

In Allopatric speciation, populations can become _______ in many different ways. List a couple

Answer 46

separated; environmental change, dispersal to an isolated area

Question 47

Allopatric speciation in forest frogs

Answer 47

* Populations become isolated in different areas * If enough gene flow occurs the populations will remain genetically similar * If gene flow is lacking, populations diverge * Overtime, if individuals from the diverging populations can no longer reproduce, speciation has occurred

Question 48

What occurred almost 500 million years ago?

Answer 48

the Cambrian explosion