Topic 1: Evolution Flashcards
1
Q
Evolution
A
Gradual change of population of organisms over time
2
Q
Natural Selection
A
Important driver of evolution
3
Q
Artificial Selection
A
Human - mediated evolution
4
Q
Agents of Selection
A
Factors that promote natural selection
5
Q
Agents of Selection Examples
A
- limited food
- habitat
- predation
- competition
- disease
6
Q
Population
A
A group of interbreeding individuals of a species that live together in a specific place
7
Q
Evolution happens at the _________ level
A
population
8
Q
Evolution depends on……
A
- Variation among a population
- Heritability of that variation
9
Q
Adaptations
A
Inherited aspects of an individuals that makes it better suited to a particular environment that other individuals
10
Q
Fittness
A
Individual reproductive success
11
Q
Fitter organisms have more _________ offspring
A
Surviving
12
Q
3 Aspects of Fitness Important to Understand Evolution
A
- Fitness is a relative concept
- A trait is only adaptive if it increases fitness
- The traits that increase fitness may change
13
Q
Mutations
A
Random, habitable change in DNA sequence
14
Q
Mutations may come from…
A
- errors in DNA
- physical agents
- chemical agents
- biological agents
15
Q
Generation Time
A
Rate of change within a population is determined by generation time (average difference in age between a parent and its offspring)
16
Q
Experimental Evolution
A
- Simulates evolution in nature in a controlled environment (lab)
- Can span much time to study many generations
17
Q
The Scale of Nature
A
Aristotle created a ladder liked classification of nature (scala Naturae)
18
Q
Taxonomy
A
Linnaeus developed branch of biology that classifies organisms
19
Q
Biogeography
A
Studies of the world distribution of plants and animals (raised question about the scale of nature)
20
Q
Perfecting Principal
A
New theory the Stuart’s simple organisms evolve to become more perfect and move up the scale of nature (proposed by Larmark)
21
Q
3 Areas of Study for the Basis of Darwin’s Insights
A
- Geology and fossil records
- Geographic distribution of species
- Comparative morphology of species
22
Q
2 Key Concepts of Darwin’s Theory of Evolution
A
- Descent with modification
- existing species descended from ancestral species - Natural Selection
- natural selection in the mechanisms of evolution
23
Q
Variation is _________
A
Inherited
24
Q
Adaptive Evolution
A
- Process that results in a better fit between organisms and their living environment
- Leads to adaption specific conditions
25
Natural selection favours the characters of organisms and allows for a greater ________ __________ in a given environment
Relative fitness
26
Evolutionary Evidence
1. Fossil Records
2. Homologies
3. Embryology
4. Molecular Biology
27
Fossil Records
- show organism is that appear in historical sequence
- link ancestral species with the living species show changes in sedimentary a rocks (strata)
28
Comparative Anatomy
Compares body structures between different species, and shows that evolution is a remodelling process
29
Homologous Structures
Similar anatomical structure resulting form common ancestor, but often different functions
30
Morphology
The study of comparing animal shapes
31
Vestigial Structures
Redundant structures that might have been useful for ancestors
32
Comparative Embryology
Compares development in early stages
33
Darwin’s Theory
- descent with modification
- natural selection
34
Are humans still evolving?
Yes
35
The Modern Synthesis
- Integrates data from evolutionary evidence
- Natural selection is not the only mechanism of evolution
- Change happens gradually, mutations do NOT play as big of a role as once believed
36
Phylogenetic Trees
Hypotheses about evolutionary relationships among a group of organisms
37
Genotype
Genetic make up of an organism
38
Phenotype
Observable or expressed traits of an organism
39
Phenotype ______ upon the genoptpye
depends
40
Genotype can be influenced?
True, by environmental factors
41
Mutation
Changes in DNA sequence (change cellular instructions)
42
What mutations are important?
Those that pass to the offspring
43
Causes for mutation
- Defective cell division
- Environmental toxins
44
Sexual Reproduction
Production of parental gametes accounts for genetic variation
45
Sexual Reproduction + Mutations = ?
Genetic variation of individuals and then in population
46
Micro evolution
Change in populations gene pool over generations (single spescies over short amount of time)
47
Gene Pool
All alleles at all gene loci in all individuals in a population
48
The Origin of Species
Evolution by natural selection explains how life on Earth has evolved over time
49
50
Macro evolution
The broader pattern of evolutionary change over longer periods of time (more than an individual species)
51
Speciation
The emergence of a new species
52
Allele
Different form of the same gene
53
Allele Frequency
Proportion of a particular allele (variant of a gene) among all elements copies in a gene pool
54
Why keep gene pools of an evolving population separated from dilution?
So new species can take place (speciation)
55
Speciation vs. Anagenesis
S: Looks like ancesetor
A: Does not look like ancestor
56
What can cause change in allele frequency?
- mutations
- sexual reproduction
- gene flow
- natural selection
57
Gene Migration / Gene Flow
Movement of gene from on population to another
58
Allopathic Speciation
Population separated by geographic barriers
59
Geologic isolation allows new species to arise by?
- maintaining the gene pool
- enhancing allele frequencies
- preventing gene flow
60
Archipelogo
Chain, cluster, or collection of islands
61
Adaptive Radiation
Evolution of many diverse species from a common ancestor
62
Sympatric Speciation
Formation of new species form an ancestral species inhabiting in the same geographical region
63
What facilitates sympatric speciation by promoting reproductive isolation in the same area?
- sexual selection
- habitat differentiation
- polyploidy
64
Habitat Differentiation
Habitats can vary within the same area
65
Ploidy
Number of different copies of each chromosome present
66
Polyploid
State of a cell having multiple set of chromosomes beyond the wild-type set most likely due to errors in cell division
67
Systematic Biology
Discipline of biology that focuses on identifying and classifying organisms to determine their evolutionary relationships
68
Taxonomy
Science of identifying and classifying organisms into an ordered system that indicates thier natural relationships
69
Phylogeny
Evolutionary history of a group of organisms
70
Hierarchy of Classification
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
71
Basic Phylogenic Tree
Describes ancestral relationships between groups of individuals
72
Evolutionary Phyogenitc Tree
Branching diagram showing the hypothetical evolutionary relationships among biological species based on their structure and molecular similarities (homologies)
73
2 Major Goals of Systematic Biology:
1. Taxonomy
2. Reconstruction of phylogeny
74
Who developed Binomial Nomenclature?
Linnaeus
75
Importance of Systematci Biology
- enhance understanding of evolution
- control pests and diseases
- identify endangered species
- choose organisms for research
76
Binomial Nomenclature composed of:
Genus and species
77
Genus
First part in Binomial Nomenclature (capitalized)
78
Species
Last part in Binomial Nomenclature (not capitalized)
79
Taxon
Group of organisms within a particular taxonomic hierarchy
80
Homoplasy Structures
Similar anatomical structures within different species that resemble each other and have some functions but do not have a common ancestral origin
81
Phylogeny based on Evidence
1. Fossil records
2. Homologous structures
3. Ancestral Characters
4. Derived Characters
5. Morphology
6. Physiological functioning
7. Patterns of behaviour
82
Ancestral Characters
Old forms of traits
83
Derived Characters
New forms of traits, relative to other organisms
84
Molecular Clock
Seen differences in nucleic acid or amino acid sequences
85
Large Differences in DNA sequences =
Divergence in the distant past
86
first part in Binomial Nomenclature (capitalized)
Genus
87
Small Differences in DNA sequences =
More recent common ancestor
88
Outgroup Comparison
Used to compare the groups under study with more distantly related species that are not included in the analysis (can identify ancestral and derived characters)
89
Parsimony
The simplest explanation that can explain the data in preffered
90
Anagenesis
Evolutionary changes may accumulate slowly in a lineage when the environment shifts
91
Monophyletic Taxa
Includes one ancestral species and all the descendants
92
Polyphyletic Taxa
Includes species form separate lineages
93
Paraphyletic Taxa
Contain an ancestor and some, but not all descendants
94
Traditional Evolutionary Systematics
Use phenotypic similarities and differences to infer evolutionary relationships
95
Cladistic Evolutionary Systematics
Use only evolutionary relationships to classify organisms
96
Clade
Monophyletic taxon to reflect the branching pattern of evolution
97
Cladogram
Tree made of clades
98
99
What are the 2 kinds of Speciation?
1. Allopathic
2. Sympatric
100
