Chapter 02 pt 1

Question 1

what is natural selection?

Answer 1

individuals with the most beneficial characteristics are the most reproductively successful

Question 2

what does natural selection explain about organisms?

Answer 2

how traits become more prevelent in populations over time

Question 3

theory of evolution states that:

Answer 3

genetic change of a population over time leads to physical changes

Question 4

What are the 4 tenets that explain natural selection?

Answer 4

1. individuals within a population vary
2. many traits are passed from parent to offspring
3. populatons should grow exponentially but do not
4. individuals with beneficial traits will survive and pass down their triats

Question 5

what are different selective agents that drive natural selection?

Answer 5

intra and interspecific

Question 6

intraspecific

Answer 6

mate choice, competition

Question 7

interspecific

Answer 7

predation, parasitism

Question 8

fitness

Answer 8

the number of viable offspring an individual produces, and amount of genetic information it passes down

Question 9

mutation

Answer 9

a heritable chang ein a gene or chomosome, random evolutinary force

Question 10

microevolution

Answer 10

evolution on a small scale

Question 11

artificial selection

Answer 11

humans slect animals to breed together based on prefered traits

Question 12

macroevolution

Answer 12

evolution on a larger scale

Question 13

sexual selection

Answer 13

process that leads to adaptations that increase reproduction chances

Question 14

phylogeny

Answer 14

history of the evolution of a species or group

Question 15

Homologus structures

Answer 15

a trait shared by 2 or more species due to a shared common ancestor

Question 16

analogous structures

Answer 16

trait shared by 2 or more due to simular natural selection pressures

Question 17

convergent evolution

Answer 17

simular adaptations due to simular enviornmental contraints

Question 18

phylogenetic trees

Answer 18

shows the history of evolution of a species or group and can help distinguish between homologies and analogies

Question 19

taxa

Answer 19

group/ species placed at ENDS of branches

Question 20

Characters

Answer 20

placed at opposite of taxa names

Question 21

root

Answer 21

at the bottom of the phylogenetic tree

Question 22

basal/ ancestral/ primative species

Answer 22

evolved early on in time

Question 23

derived species

Answer 23

evolved later on in time

Question 24

nodes

Answer 24

where two branches come togehter, represent a shared common ancestor between two or more species

Question 25

clade

Answer 25

group made of an ancestor and all its decendants

Question 26

sister taxa

Answer 26

adjacent branches on a tree that form a clade together, (closely related)

Question 27

plesiomorphies

Answer 27

primative/ inherited form a common ancestor

Question 28

synapomorphies

Answer 28

derived traits

Question 29

what are the 5 mechanisms for evolution?

Answer 29

1. natural selection
2. mutations
3. genetic drift
4. gene flow
5. assortative mating

Question 30

natural slection

Answer 30

adaptations

Question 31

mutations

Answer 31

random heritable change in gene or chromosome

Question 32

what is unique about mutations?

Answer 32

• ultimate source of genetic variation
• new alleles
• makes good and bad traits

Question 33

genetic drift

Answer 33

change in genetic variation as a result of random chance

Question 34

meiosis

Answer 34

creates genetically unique gametes that increase genetic variation

Question 35

bottleneck effect

Answer 35

traits lost due to shrinking population size

Question 36

founder effect

Answer 36

small number of individuals go to islands

Question 37

gene flow

Answer 37

movement of genetic info among populataions bc of migration

Question 38

imigration

Answer 38

import

Question 39

emigration

Answer 39

export

Question 40

assortive mating

Answer 40

individuals mate non- randomly (choose mate like humans)

Question 41

sexual selection

Answer 41

process that leads to adaptations that increase reproduction chances

Question 42

what is the ultimate source of genetic variation in the gene pool? and why

Answer 42

mutations, they introduce new alleles into the gene pool

Question 43

what factors can lead to genetic drift?

Answer 43

immigration, emigration, and the bottleneck effect

Question 44

what happens to genetic variation when there is gene flow?

Answer 44

• increase genetic variation within a population
• reduced genetic variation among populations

Question 45

What kind of selection results from assortative (non-random) mating? How does this
differ from natural selection?

Answer 45

sexual selection, this differes from natural selection becasuse they are choosing a mate and leads to choosing adaptations that increase reproductive chances

Question 46

What are the 4 requirements for natural selection to act on a behavior?

Answer 46

1. variaton
2. heritability
3. limited recources leading to COMPETITION
4. fitness consequences

Question 47

Why is it important to build a phylogenetic tree using homologous traits rather than
analogous traits?

Answer 47

bc homologuous traits are ancestor related like the goal of trees is to show ancestoral relations

Question 48

What kind of data are used to construct a phylogenetic tree?

Answer 48

homologus and analogous traits