evolution Flashcards
meaning of evolution
change over time
organisms related by decent from a common ancestor
evolution through natural selection
Bishop James Ussher
interpreted genesis
said earth was made in 4004 BC
darwin drew inspiration from
Taxonomy Geology Paleontology Demography Evolutionary biology
taxonomy
Classifying living organisms and identify biological relationships
Wanted to present God’s plan for creation
Not evolutionary thinkers
Carolus Linnaeus
Developed classification system for and animals Systema Naturae Included humans with animals Humans grouped with apes Binomial nomenclature
geology
reconstructing the changing surface of the earth
Charles Lyell
Uniformitarianism
Forces active in past are same forces as those active in present
Earth changes by flood erosion, drought, wind
“Stacking” of changes = strata or layers
Principles of Geology (1830-1833)
Earth much older than Ussher suggested
paleontology
reconstructing the history of life on earth
Georges Cuvier
Father of zoology, paleontology, and comparative anatomy
Theory of Catastrophism
Each stratum of earth contained different fossils
Earth’s history one of subsequent disasters resulting in extinctions and repopulations
Demography
Study of populations
Birth rates
Death rates
Factors that influence these
thomas Malthus
Human population doubles every 25 years
Food production increase only in a arithmetic progression
Species overpopulation checked by the struggle for existence
Competition for limited resources
Evolutionary Biology
Early attempts to explain transformation of life forms
Fossils were early forms of species
Jean Baptiste Lamarck
Theory of Transformism Organs develop to satisfy needs Inheritance of acquired characteristics Interaction of organic forms with their environment Spontaneous generation Popularized idea of evolution
Alfred Russel Wallace
Expeditions to the Amazon and Malayan Archipelago
Similar ideas to darwin
Also influenced by Malthus
July 1, 1858 Wallace and Darwin presented joint papers to the Linnean Society
origin of species
Mutability of species
Species evolve from other species via Natural Selection
Descent with modification
Evolution through Natural Selection
Surviving offspring have advantageous characteristics for survival
These offspring survive and reproduce themselves
Over time the frequency of these advantageous traits increases
darwin’s evidence
Domestication of plants and animals Breeding Geographic distribution of life forms Geological and paleontology record Comparative anatomy Vestigial organs Embryology
embryology
Ontogeny recapitulates phylogeny
More general characteristics appear before more specific ones
Animals progressively diverge from related forms during development
Ontogeny recapitulates phylogeny
Early stages of young animals resemble early stages of primitive forms
Philosophical Materialism
Matter is the stuff of all existence
Mental and spiritual phenomena are by-products
Other evolutionists spoke of vital forces, organic striving
Wallace claimed the human mind was a divine creation
Darwin did not address issue of human evolution until 1871
Descent of Man
Evolution through Natural Selection
A trait must be inherited
Natural selection cannot occur without variation in a population
Fitness is relative
Evolution is not directed (random)
Selection is a non-random (directed) force
Occurs at the level of the individual
Acts on the phenotype but affects the genotype
Works through differential net reproduction
number of offspring born - number of offspring that die before reaching reproductive age
If die before reproducing then it is as if you never lived
With breeding isolation can lead to speciation
`Can account for high degree of sexual dimorphism
types of evolution
Directional
Stabilizing
Disruptive
Bimodal
evolution
Occurs at the level of the population, species
Occurs because of differential net reproduction
parallel evolution
Develop of similar structures that occur independently and are probable due to similar evolutionary conditions
convergent evolution
Development of structure in remotely related forms that superficially resemble each other
divergent evolution
Closely related species become more morphological divergent due to different evolutionary pressures
darwin’s failures
Unable to explain source of variation
Failed to know mechanism by which parents transmit traits
