Natural Selection Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Primary sources of evidence supporting evolution:

A
  1. The fossil record
  2. Comparative morphology
  3. Biogeography
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Fossils and the fossil record

A

-Traces of past organisms that give a visual of evolutionary change over time
-Can be dated by examining of carbon 14 decay

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Comparative morphology

A

Analysis of structures of living and extinct organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Homology

A

Characteristics in related species that have similarities even if the functions differ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Embryonic homology

A

Many species have similar embryonic development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Vestigial Structures

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Molecular homology

A

Many species share similar genetic information

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Homologous structures

A

Characteristics that are similar in two species because they share a common ancestor
ex. Arm bones of many species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Convergent evolution

A

Similar adaptations that have evolved in distantly related organisms due to similar environments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Analogous structures

A

Structures that are similar but have separate evolutionary origins
Ex. Wings in birds vs bats vs bees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Common ancestry evidence

A
  1. Membrane bound-organelles
  2. Linear chromosomes
  3. Introns in genes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Biogeography

A

The distribution of animals and plants geographically

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Systematics

A

Classification of organisms and determining their evolutionary relationships

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Taxonomy

A

Naming and classifying species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Phylogenetics

A

Hypothesis of evolutionary history
-Use phylogenetic trees to show evolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

To determine evolutionary relationships, scientists use

A

-Fossil records
-DNA, proteins
-Homologous structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Phylogenetic trees

A

diagrams that represent the evolutionary history of a group of organisms, similar to cladograms except trees show the amount of time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Cladograms

A

-Each line represents a lineage
-Each branching point is a node
-Root is the common ancestor of all the species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Sister taxa

A

Two clades that emerge from the same node
<

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Basal Taxon

A

Lineage that evolved from the root and remains unbranched -

21
Q

Synapomorphy

A

A derived character shared by clade members
Derived characteristics: similarly inherited from the most recent common ancestor of an entire group
Ancestral characteristics: Similarity that arose prior to the common ancestor

22
Q

Monophyletic group

A

Includes the most recent common ancestor of the group and all of it’s descendants

23
Q

Paraphyletic group

A

Includes the most recent common ancestor of the group, but not all of it’s descendants

24
Q

Polyphyletic group

A

Doesn’t include the most recent common ancestor of all members of the group

25
Q

Species

A

Group able to interbred and produce viable, fertile offspring

26
Q

Speciation

A

Formation of a new species

27
Q

Allopatric speciation

A

-Physical barrier divides pop. or a small pop. is separated from main pop.
-Populations are geographically isolated
*prevents gene flow
*Often caused by natural disasters

28
Q

Sympatric

A

-New species evolves while still inhabiting the same geographic region as the ancestral species
*usually due to the exploitation of a new duty within the population

29
Q

Speciation occurs due to

A
  1. Prezygotic
  2. Postzygotic
30
Q

Prezygotic barriers

A
  1. Habitat isolation
  2. Temporal isolation
  3. Behavorial isolation
  4. Mechanical isolation
  5. Gametic isolation
31
Q

Habitat isolation

A

Species live in different areas or they occupy different habitats within the same area

32
Q

Temporal isolation

A

Species breed at different times

33
Q

Behavioral isolation

A

Unique behavioral patterns and rituals separate species

34
Q

Mechanical isolation

A

Reproductive anatomy of one species doesn’t work with the anatomy of another species

35
Q

Genetic isolation

A

Proteins on the surface of the gametes don’t allow for sperm and egg to fuse

36
Q

Postzygotic-reduced hybrid viability

A

genes of different parent species may interact that impair hybrids development or survival

37
Q

Reduced hybrid fertility

A

Hybrid can develop into a healthy adult, but is sterile

38
Q

Hybrid breakdown

A

The hybrid of the first generation may be fertile, but when they mate again or with another species offspring will be sterile

39
Q

Microevolution

A

Change in allele frequencies within a single species or pop

40
Q

Macroevolution

A

Large evolutionary patterns

41
Q

Punctuated equilibrium

A

Rapid evolution

42
Q

Gradualism

A

Slow evolution over hundreds, thousands of years

43
Q

Divergent evolution

A

Groups with the same common ancestor evolve and accumulate differences resulting in the formation of a new species

44
Q

Adaptive radiation

A

If a new habitat or niche becomes available, species diversifies rapidly

45
Q

Convergent evolution

A

Two different species develop similar traits despite having different ancestors

46
Q

Origins of life

A

-Earth formed 4.6 billion years ago
-Life suitable 3.9, fossils found 3.6
*cyanobacteria

47
Q

How did life arise?

A

Early life contained inorganic molecules, these could have synthesized organic molecules due to free energy and abundant oxygen

48
Q

Miller and Urey hypothesized

A

Organic molecules served as building blocks for macromolecules

49
Q

RNA world hypothesis

A

Proposes that RNA could have been the earliest genetic material