AP Bio Unit 7: Natural Selection

studied byStudied by 16 people
5.0(1)
Get a hint
Hint

biogeography

1 / 64

flashcard set

Earn XP

Description and Tags

65 Terms

1

biogeography

the geographic distribution of species

New cards
2

evolution

change in the genetic makeup of a population overtime; descent with modification

New cards
3

natural selection

a process in which individuals that have certain traits tend to survive and reproduce at higher rates than other individuals because of their traits

New cards
4

artifical selection

the selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits

New cards
5

population

a group of individuals of the same species that live in the same area and interbreed to produce fertile offspring

New cards
6

gene pool

a population genetic makeup; consists of all copies of every type of allele

New cards
7

microevolution

small scale genetic changes in a population

New cards
8

genetic drift

chance events that cause a change in allele frequency

New cards
9

bottleneck effect

when a large population is drastically reduced by a non-selective disaster

New cards
10

founder effect

when a few individuals become isolated from a large population and establish a small population with a gene pool that differs from the large population

New cards
11

gene flow

the transfer of alleles into or out of a population due to fertile individuals or gametes

New cards
12

relative fitness

the number of surviving offspring that an individual produced compared to others left in population

New cards
13
<p>directional selection</p>

directional selection

selection on the extreme towards one phenotype

New cards
14
<p>stabilizing selection</p>

stabilizing selection

selection towards the mean away from extremes

New cards
15
<p>disruptive selection</p>

disruptive selection

selection against the mean and towards the extremes

New cards
16

sexual selection

a type of natural selection that explains why many species have showy unique traits; selection for mating based on certain traits (affects fitness)

New cards
17

Hardy-Weinberg Equilibrium

a model used to assess whether natural selection or other factors are causing evolution at a particular locus

New cards
18

Hardy-Weinberg principle

frequency of alleles and genotypes in a population will be remain constant from generation to generation provided that ONLY Mendelian segregation and recombination of alleles are at work

New cards
19

five conditions of Hardy-Weinberg equlibrium

  • No mutation

  • No gene flow

  • No natural selection

  • Random mating

  • Large population size

New cards
20

fossils

remains or traces of past organism

New cards
21

fossil record

gives a visual of evolutionary change overtime

New cards
22

comparative morphology

analysis of the structure of living and extinct organisms

New cards
23

homology

characteristics in related species that have similarities even if structures differ

New cards
24

vestigial structures

structures that are conserved even though they no longer have a use

New cards
25

molecular homology

similarities in DNA and AA sequencing between species

New cards
26

homologous structures

characteristics that are similar in 2 species because they have a common ancestor

New cards
27

convergent evolution

similar adaptation that have evolved in distantly related organisms due to similar selection presures

New cards
28

analogous structures

structures that are similar but have separate evolutionary origins

New cards
29

biogeography

the distribution of animals and plants geographically

New cards
30

systematics

classification of organisms and determining their evolutionary relationships

New cards
31

taxonomy

naming and classifying species

New cards
32
<p>phylogentic trees</p>

phylogentic trees

diagrams that represent the evolutionary history of a group of organisms

New cards
33
<p>node</p>

node

branching point; represents common ancestors

New cards
34
<p>sister taxa</p>

sister taxa

two clades that emerge from the same node

New cards
35
<p>bassal taxum</p>

bassal taxum

a lineage that evolved from the root and remains unbranched

New cards
36

synapomorphy

a derived trait shown by clade member

New cards
37

derived charateristic

similarly inherited from the most recent common ancestor of an entire group

New cards
38

ancestral characteristic

similar trait that arose prior to common ansestor

New cards
39

outgroup

a lineage that is least closely related to the rest of the organisms

New cards
40

monophyletic group

includes the most recent common ancestor of the group and all its descendants (clade)

New cards
41

paraphyletic group

includes the most recent common ansestor but not all of it’s desendents

New cards
42

polyphyletic group

does not include most recent common ancestor of all members of the group

New cards
43

species

a group able to interbreed and produce viable offspring

New cards
44

speciation

formation of a new species

New cards
45

allopatric speciation

physical barrier divides population or a smaller group of the population is separated from the main population preventing gene flow

New cards
46

sympatric speciation

a new species evolved while still inhabiting the geographic regions of the ancestral species, usually due to the exploration of a new niche

New cards
47

2 types of reproductive isolation

prezygotic and postzygotic barriers

New cards
48

prezygotic barriers

prevent mating or hinder fertilization

New cards
49

habitat isolation

species live in different areas or occupy different habitats in the same area

New cards
50

temporal isolation

species breed at different times of the day, year or season

New cards
51

behavioral isolation

unique behavioral patterns and rituals separate species (sexual selection)

New cards
52

mechanical isolation

the reproductive anatomy of species does not fit the anatomy of another

New cards
53

genetic isolation

proteins on the surface of gametes do not allow for sperm and egg to fuse

New cards
54

reduced hybrid viability

the genes of different parent species many interact in a way that impair the hybrids development or survival

New cards
55

reduced hybrid fertility

a hybrid can develop into a healthy adult but is sterile

New cards
56

hybrid breakdown

the hybrid of the first generation may be fertile, but when they mate with a parent species or one another, their offspring will be sterile

New cards
57

microevolution

change in allele frequencies within a single species or population

New cards
58

macroevoltion

large evolutionary patterns

New cards
59

stasis

no change over long periods of time

New cards
60

punctuated equilibrium

when evolution occurs rapidly after long periods of statis

New cards
61

gradualism

when evolution occurs slowly over hundreds, thousands or millions of years

New cards
62

divergent evolution

groups with the same common ancestor evolve and accumulate differences resulting in the formation of new species (homologous traits)

New cards
63

adaptive radiation

if a habitat or niche becomes available, species can diversify rapidly

New cards
64

convergent evolution

two different species develop similar traits despite having different ancestors (analogus traits)

New cards
65

extinction

the termination of a species

New cards

Explore top notes

note Note
studied byStudied by 9 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 3 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 14 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 41 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 55 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 20 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 5 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 6 people
Updated ... ago
5.0 Stars(1)

Explore top flashcards

flashcards Flashcard84 terms
studied byStudied by 10 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard25 terms
studied byStudied by 4 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard156 terms
studied byStudied by 2 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard116 terms
studied byStudied by 55 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard101 terms
studied byStudied by 16 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard29 terms
studied byStudied by 3 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard29 terms
studied byStudied by 1 person
Updated ... ago
5.0 Stars(1)
flashcards Flashcard95 terms
studied byStudied by 29 people
Updated ... ago
5.0 Stars(1)