midterm Flashcards
Define evolution
origin of entities possessing different states of one or more characteristics - and changes in the proportion of those entities over time
Define biological evolution
change over timein the proportion of individual organisms within a population differing genetically in one or more traits
Darwin defined evolution as…
descent with modification
What was Platos view on the natural world?
Platonic idealism - there is an ideal form that is imperfectly represented by earthly representations
- ideal forms can be perceived only through contemplation
What was Aristotles view on the natural world?
Essentialism - all members of a class of objects share certain properties that distinguish them from other classes
- species are immutable
- classified species using scala naturae
What was George Cuviers contribution?
- described extinction
Catastrophism - species are created by catastrophic extinction events
Father of palaeontology
What was James Huttons contribution?
- Uniformitarianism - natural processes that operated in the past are still ongoing in the present
What was Charles Lyells contribution
- influence on Darwin
- popularized Huttons uniformitariansm hypothesis
- change can happen on larger timescales
What was Lamarcks contribution?
- inheritance of acquired characteristics
- thought evolution had a goal
- traits acquired by use vs disuse
- transformism
Early influence on Darwin
What were the two main theories in the Origin of Species?
- descent with modification and natural selection
What are the five inter related theories of evolution?
- Evolution as such
-Common descent - Gradualism vs saltations
- Population variation vs. platonic idealism
- Natural selection - mechanism
Why was Darwin wrong about his mode of inheritcance via blending?
would ultimately reduce variation
What are the two main schools of thought on variation of traits?
- Mendelians - large differences - discrete traits - color
- Biometricians - small differences - quantitative traits - height - believed in natural selection
What did Fisher contribute?
- natural selection could work with mendelian inheritance
What is the modern synthesis?
Neo Darwinism
- mendelian inheritance and natural selection
Two types of phenotypic variation
discrete (one loci) and continuous (multiple loci)
Evolution within species and over shorter time scales is known as?
- microevolution
Evolution across species and over longer time scales is known as?
macroevolution
What is the primary ingredient for evolutionary change?
intraspecific variation
Three non genetic forms of inheritance?
- cultural
- maternal effects
- epigenetics
What is cultural inheritance?
- cross generational similarity in non-genetic behavioral traits, based on processes such as non-random imitation
- tool use in non humans
- song learning in birds (language?)
What are maternal effects? (/ parental effects)
- non genetic effect of a mother on the phenotype of her offspring due to factors such as cytoplasmic inheritance, transmission of symbionts from mother to offspring or provisioning.
- hormonally mediated
What is epigenetic inheritance?
- inherited changes in gene expression or phenotype that are not based on changes in DNA sequence
- due to DNA methylation
What is an example of evolutionary trade offs?
- offspring
- generally either many small simple offspring or few larger offspring