EVO Flashcards
1
Q
What is Teleology?
A
Everything has a final cause in nature, and are designed with a purpose.
2
Q
What was Aristotles theory?
A
Teleology
3
Q
What was Linnaeus theory?
A
Taxonomy and Binomial Nomenculture.
4
Q
What was the Hutton theory?
A
Gradualism and Deep Time
5
Q
What was Lamarck’s theory?
A
Inheritance
6
Q
What was Cuviers theory?
A
Extinction and Palaeontology
7
Q
What was St. Hilaires theory?
A
Homology (but the term wasnt created by him)
8
Q
What was Lyells theory?
A
Uniformatarism
9
Q
What was Darwins theory?
A
Natural selection, leading to Metaphysical Naturalism
10
Q
What 4 things happened after Darwin?
A
> End of teleology
Gradualism
Human primate relationship considered
Uniformatarism accepted
11
Q
What six points did the Origin of Species make?
A
> Domestication > Natural selection > Geology > Diversity > Gradualism > Sexual behaviour
12
Q
What does Homology mean?
A
A very similar trait which is present in two species, due to sharing a common ancestor
13
Q
What four points did the evolution theory consider?
A
> Homology
Development
Vestigial organs
The fossil record
14
Q
Features of the evolutionary process?
A
> Gradual
Non random
Biological traits become mkre or less common
Greater fitness means greater reproductive success
15
Q
What evolutionary propositions were put forward?
A
> More offspring produced than survived
Intraspecies competition
Variation between individuals within a species
Favoured traits will increase in frequency
Genetic drift is a chanced change in the allele frequency
16
Q
What are the five selection modes?
A
> Stabilizing > Directional > Diversification > Sexual > Artificial
17
Q
What is the law of dominance?
A
Parents with pure and contrasting traits are crossed to produce a heterozygous offspring only showing the dominant allele
18
Q
What is the law of segregation?
A
Alleles responsible for a trait seperate during gamete formation
19
Q
What does Independent assortment mean?
A
The random orientation of chromosomes at the equator during metaphase 1 leads to the random distribution of the alleles.
20
Q
What are the exceptions of independent assortment (when does it not happen)?
A
> linkage
unnatural inheritance
dihybrid inheritance
21
Q
What is the chromosomal theory of inheritance?
A
> Nuclear substance controls cells form and function.
Haploid gametes produced - in order to combine during fertilization.
Inheritance patterns linked by the position of genes a chromosome.
22
Q
What 6 types of gene mutations are there?
A
> Substitution > Deletion > Duplication > Insertion > Horizontal gene transfer > Structural changes
23
Q
What happens when mutation frequency increases?
A
Speciation increases.
24
Q
Name three examples of mutations in animals?
A
> Naked Mole Rat
Gray horses
Bovine Chrond. Dwarfism
25
What is unit of heredity?
Evolution depends o the allele frequency changes, and this enables populatioms to continue through time
26
What is the hardy-weinberg principle?
A principle that can work out whether or not a population is evolving.
27
What is the Bottleneck effect?
A drastic change in population size, where the survivors must have had a different genotype to the rest of the population.
28
What is the Founder Effect?
When individuals from a population move to form a new population, and therefore, species with a different allele frequency.
29
Name some disadvantages of domestication?
> There are only certain traits selected - restricts gene flow.
> Restricts variation.
30
What are the 4 rules of Natural Selection?
> Organisms are genetically varied.
> At least one trait from the parent is inherited by the offspring.
> Some will have increased breeding and survival success than others.
> Some traits will be favoured more than others, thus lasting longer in the population.
31
What were the 5 main discoveries which led up tothe modern synthesis?
```
> Micro macro evolution
> Palaeontology
> Population genetics
> Taxonomy
> Mutational Analysis
```
32
What is mutational analysis?
The study of inheritance of a mutation through generations
33
What two discoveries did the modern synthesis connect together?
Genes and selection mechanisms
34
What are the 4 rules of the modern synthesis?
> Variation is down to chance, by gene segregation, recombination and mutation
> Diversification due to speciation
> Changes in genes have phenotyoic effect
> Evolution causes gene frequency changes, due to genetic drift, gene flow and natural selection
35
What is allopatric speciation?
> Geographical isolation
| > Have different selection pressures due to occupying two different areas.
36
What is sympatric speciation?
> Ecological barriers
| > Differences in food, time of day they are active ect
37
What is parapatric speciation?
> Overlapping territories
| > Differences in behaviour, human population, mutations, selection pressures abiotic factors.
38
What are 3 differences between the modern sythesis and darwinian evolution?
> Polygenic genes mostly determine variation between individuals in a population.
> More than one selection mechanisms, not just natural selection.
> Gradual changes are made up of lots of microevolutions to make up one macroevolution.
39
What is a polygenic inheritance ?
inheritance occurs when one characteristic is controlled by two or more genes.
40
What is microevolution?
Change in allele frequency of a population over time which eventually leads to a relatively small change in the species, which can sometimes lead of speciation.
41
What is macroevolution?
A major change in a lineage which can lead to the origin, diversifiction or extinction of a major group.
42
How can we measure diversity?
The total numbet of taxa
43
How can we measure disparity?
Differences between taxa
44
Give a brief history through time (13)?
```
> Origin
> Photosynthesis
> Multicellular cells
> Cambian explosion
> Silerian
> Denovian
> Permian
> Reptiles and dinos
> Mass extinction
> Mammals
> Grassland
> Ancestoral humans
> Ice age
```
45
What are the 5 mass extinctions?
```
> Ordovician -> Silerian
> Late devonian
> Permian -> triassic
> Triassic -> jurassic
> Cretaceous -> tertiary
```
46
What are the three fauna which are seen to be the 3 mass originations?
> Cambrian
> Paleozoic
> Modern
47
What is anagenesis?
Gradual transformation of one species into another
48
What is Cladogenesis?
Splitting of a species into two or more lineages along the tree
49
What is punctuated evolutionay pace?
When stasis occurs, isolation occurs, and this allows for rapid changes due to the smaller populations and thus, the smaller gene pool.
50
What are the 7 stages of punctuated equilibria?
> Stasis of evolution.
> Isolation mechanism.
> Rapid change and strong selection of small populations
> No preservation of transitional fossils
> Reintroduction of isolated populations and sister lineage
> Expansions and stasis is isolated population - outcompetes sister
> Preservation of isolated population which grows and allows stasis to begin again.
51
What is punctuated equilibria?
Theory that the evolution of species proceeds with long periods of relative stability interspersed with rapid change.
52
How can a trend be identified?
> Good fossil record
| > Known evolutionary relationships
53
What is Copes rule?
```
Lineages tend to increase in body size over evolutionary time due to:
> Dominate resources
> Dominate opponents
> Higher breeding success
> Higher survival rate
> Better fitness
```
54
What is direct competitive exclusion?
The increase in clade 2 causes the decrease in clade 1
55
What is incumbent replacement?
Clade1 extinction causes the diversification of clade 2
56
What is Bergmanns rule?
> Larger size = Colder climates (smaller SA:V ratio --> maintain temperature easier)
> Smaller size = warmer climates
57
What is Allens rule?
Colder climates = smaller appendages (limbs)
58
Is it abiotic or biotic that determines microevolution and why?
> Biotic
| > Causes smaller changes
59
Is macroevolution biotic or abiotic?
> Abiotic
| > due to the environment being able to cause rapid changes in a species
60
What are 4 examples of prezygotic barriers and what does it mean?
```
Inhibits mating
> Habitat
> Behavioural
> Temporal
> Mechanical
```
61
What is postzygotic barriers and what are 4 examples of it?
Inhibits fertilisation or formation of healthy embryo - Hybrid viability reduced
> Gamete incompatibility
> Hybrid sterilisation
> Hybrid mortality (not enough DNA; cells divide mitotically but then die )
> Hybrid breakdown (limited times to reproduce)
62
What does hybridisation mean?
The act or process of mating organisms of different varieties or species to create a hybrid.
63
What are the 3 outcomes of hybridisation and explain what they mean?
```
Reinforcement = prevents the gene flow
Fusion = extinction of gene pool stopped as the gene flow is continued
Stability = allows some gene flow but not enoughto allow the species to diverge
```
64
Define a species?
Group of organisms which all descended from a common ancestor, and who have common defining traits - they can interbreed to create fertile offspring.
65
What 6 points are needed for speciation to occur?
```
> Variation
> Isolation
> Decreased gene flow
> Selection
> Divergence
> Speciation
```
66
What sources of random variation are there?
```
> Mutation
> Regulation
> Duplication
> Segregation
> recombination
> Independent assortment
```
67
What sources of non random variation are there?
> Ontogeny
> Heterochrony
> Phenotypic plasticity
> Allometry
68
What does ontogeny mean?
Development or course of development especially of an individual organism.
69
What does Heterochrony mean?
Evolved differences in developmental timing.
70
What are the 4 models of heterochrony?
> Hypermorphosis = prolonged relative growth
> Acceleration = faster relative growth
> Progenesis = fore shortened relative growth
> Neoteny = slow relative growth
71
What is peramorphosis and what produces it?
> Exaggeration of adult characteristics
| > Caused by hypermorphosis and acceleration
72
What is paedomorphosis and what causes it?
> Retention of juvenile characteristics
| > Produced by progenesis and neoteny
73
What is dispersal?
Smaller population of main species crosses barrier from acesteral to new area and then speciation occurs.
74
What is vicariance?
The division of a group by a geographic barrier, often resulting in the evolution of related species on either side of the barrier.
75
What is archipelago speciation?
Dispersal from ancestral land to another then again and the process continues until speciation occures on each island.
76
Whats a ring species?
Neighbouring populations connected in a series where each can interbreed with the adjacent species but the starting and ending species are reproductively isolated due to being very morphologically different.
77
What is competitve exclusion?
Two species differing their ecological niches to accommodate and coexist in a stable environment.
78
What is character displacement?
A phenomenon in which species that live together in the same environment tend to diverge in those characteristics that overlap. Darwins finches seed eaters.
79
When do we use phylogentic systematics?
When we want to compare multiple taxa.
80
What is a cladogram?
diagram used in cladistics which shows relations among organisms.
81
What is synapormorphy?
> Homology features
| > Feature that shows we are all related
82
What is plesiomorphy?
> Shared trait which are primitive and are present in ancestors.
83
What is homoplasty?
> Convergent evolution
> Analogous trait
> Evolves multiple times
84
What are the advahtages of phylogenetic systematics?
```
> Quantitive
> Simple
> Computers used
> Evolutionary
> Parsimonious
> Can use different types of data
```
85
Name 4 problems with the phylogenetic systematics?
> Isnt objective
> No ancestors identified
> Hybridization and lateral gene transfer
> Evolution may not be parsimonious
86
Why is development important in evolutionary biology?
When an embryo is developing, there are similaritiesin the morphologies between the species and these commonalities can reflect common ancestry
87
How is development achieved?
Gene regulation
88
What is the theory of biogeography?
Larger the area - the more species.
89
What are the features of colonizing organisms?
> Adaptive radiation
| > Endemic species
90
Why does the island rule happen?
```
Islands tend to have :
> Limited resources
> Reduced predation
> Need to be bigger to be able to compete and gain the resources as much as possible due to the limitation of it.
> Interspecies competition
> Optimal body size
```
91
What are the 3 exceptions to the island rule?
> Bears ➡ gigantism
> Carnivores vary
> Rabbits ➡ dwarf
92
Why are elephants such good swimmers and why does this help with their diversity?
> Aquatic ancestors
> Took to water to take the load off their skeleton.
> Trunk and elastic lungs enables them to take deep breaths from their trunk with minimal effort
> This helps with their dispersal as they can move to new islands easier.
93
Give evidence of how birds breathed?
> Pneumatic bones show air sacs were present.
| > These were present in dinosaurs
94
Give evidence on how birds developed flight?
> Raised knobs on the ulna for feather attachment.
| > Ligaments prevented the feather being lost in flight.
95
What where feathers used for prior to flight?
```
> Insolation.
> Communication.
> Camouflage.
> Water repellent.
> Defence.
```
96
What are the functions of predigits in elephant feet?
> Stiffen
> Reduce stress
> Transfer loads
> More flat footed - load bearing
97
What are the stages involved in the primordial soup?
```
> Chemically reducing atmosphere
> Energy exposure
> Simple organic compounds produced
> Concentrations varied
> Complex organic polymers produced
```
98
What is panspermia?
The belief that there was an extraterrestrial origin of life
99
What was the Miller-Urey experiment? And why could this not be true ?
> Urey believed that the early atmosphere was made up of methane, ammonia and hydrogen
> Miller put together water vapour, gas and an electric spark and created amino acids.
> However, there is no evidence of ammonia or methane in the early atmosphere
100
Briefly describe the properties of hydrothermal vents?
```
> Reverse krebs cycle
> Acts as cell membrane
> Extreme conditions
> Low oxygen concentration
> Heat energy released as hot mineral rich water
```
101
What are mid oceanic ridges and vents caused by?
Sea floor spreading due to shift in plate tectonics
102
What are the 3 domains of life?
> Bacteria
> Archaea
> Eukaryotic
103
What does symbiosis mean?
A long term interaction between two biological species for a mutual benefit
104
How did eukaryotes become aerobic and photosynthetic?
An ancestor engulfed a prokaryote which had a mitochondrion and chloroplast
105
What is the animalia hypothesis?
Cells developed specialised cells and gastrulated.
106
What are choanoflagellates ?
```
> Unicellular
> Flagellated eukaryotes
> Microvilli collar
> Closest relative to metazoans
> Similar to sea sponges
```
107
What is the disadvantage of asexual reproduction?
They collect deleterious mutations through time and genetic loading occurs ; the population will go extinct
108
What is the advantage of sexual reproduction ?
As the genetic material gets recombines, there is a prevention of the deleterious mutations building up
109
What did thecambrien explosion lead to?
```
> Predation
> Taxonomic diversity
> Morphological disparity
> Body plans
> Lifestyles
> Community function and structure
> Benthic zone - bottom of de sea
> Pelagic - middle region of de sea
```
110
What are a few of the tiggers for the cambrien explosion?
> Glaciation
> Upwelling of oceans -> increase oxygen levels
> Mutation in the hox gene -> changes morphology and development constraints.
111
Definition of a agenesis ?
Gradual change involving mini changes, and when the changes are sufficient enough,this leads to speciation
112
What is a dichotomy?
A fully resolved phylogenetic tree
113
What is a polygons ?
An incomplete/unresolved phylogenetic tree
114
What is monophyletic ?
The group in question and all the ancestors and species included
115
What is paraphyletic ?
Organisms which are like the species in question, and share the same common ancestor
116
What is ployphyly?
Organisms which shouldn't be grouped together on a phylogenetic tree even though they share similar features.
117
What are the uses of cladograms (5)?
```
> Classification
> biogeographical analysis
> Paleo hypothesis
> Character sequencing
> Reconstructing diversity patterns and seek how species have changed.
```
118
What evolved first, swim bladders or lungs?
Lungs -> intermediate -> swim bladders
119
What is the main reason for evolutionary trees?
Depict recency of common ancestry
120
What is 'Mullers ratchet' ?
bad mutations building up in DNA over time - sex stops this.
121
What is genetic polymorphism?
Different phenotypes
