What is evolution?
Change in the heritable characteristics of a population over time
What are the two theories of evolution?
Lamarckism and Darwinian
What is the idea behind Lamarckism?
That frequently used structures strengthen over time and are more likely to be inherited - “inheritance of acquired characteristics”
What is the idea behind the Darwinian theory?
Natural selection
Individuals with favorable characteristics live longer (by outcompeting others) & produce more offspring => trait becomes more prevalent in population
What is a paradigm shift?
A change in the fundamental understanding of a phenomena
How exactly do adaptations/evolution happen?
Through random genetic mutations
What is sequence similarity?
Similarity in DNA/protein sequences, implying organisms are closely related
What is divergence & what is it used for?
Accumulation of mutations in DNA leads to changes in amino acid sequence of proteins
These changes are used to trace evolutionary relationships
What are comparative genomics?
Comparison of genomes - any conserved (ie useful) regions are likely result of common ancestry
What is cladistics analysis?
Cladograms (visual representation of evolutionary relationships)
What do we use evidence for evolution for?
Tracking changes to genetic sequences
What is artificial selection and what does it demonstrate?
Deliberate breeding of animals/crops with favorable traits
Demonstrates that evolution does occur
Describe the process of artificial selection
1) Overproduction of offsrping
2) Variation in heritable traits
3) Selection pressure affects survival/reproduction
4) Differential survival as an effect
5) Change of frequency of heritable trait over time
Now go interpret a cladogram
Ask which species are more closely related etc.
What is divergent evolution?
When species from a common ancestor evolve to become different species
What are homologous structures and how do they differ in modern species?
Structures inherited from common ancestors
Structures needed to solve different purposes -> diverse evolution
(pentadactyl limb)
What is convergent evolution?
When species develop similar traits due to similar challenges in the same niche despite not having a common ancestor
What are analogous structures/behaviors?
Similar structures/behaviors NOT a result of common ancestry
What is the analogous and homologous structure of bats and birds?
Analogous - can fly
Homologous - pentadactyl limb
What is speciation?
Result of divergent evolution when species splits & creates new species (cladograms)
What is the problem with speciation?
It’s hard to to distinguish unique species because species are constantly evolving
What needs to happen for speciation?
Geographical & reproductive isolation leading to prolonged gene differences -> speciation event
What is sympatric isolation?
Reproductive
What is allopatric isolation?
Geographic
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(1) Populations & Communities C 4.131
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(2) Transfer of energy and matter C 4.212
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(3) Ecological niches B 4.219
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(5) Evolution A 4.131
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(6) Diversity of Organisms A 3.1 + HL Content26
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(7) Conservation of Biodiversity A 4.212
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(8) Natural selection D 4.114
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(9) Classification & cladistics A 3.2 AHL18
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(10) Inheritance D 3.219
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(11) Cell division D 2.133
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(12) Cancer D 2.1 AHL14
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(13) Mutation D 1.313
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(14) Biotechnology D 1.3 AHL13
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(15) Epigenetics D 2.2 AHL39
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(16) Gene pools D 4.1 AHL30
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(17) Nucleic acids A 1.223
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(18) DNA replication D 1.119
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(19) Nucleic acids AHL A 1.214
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(20) DNA synthesis AHL D 1.121
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(21) Translation - protein synthesis D 1.219
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(22) Proteins B 1.222
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(23) Translation B 1.2 AHL26
