Descent With Modification Flashcards
Charles darwin’s book that focused biologist’s attention on the great diversity of organisms
On the origin of species by means of natural selection
Two points Charles darwin made in his book
- presented evidence that many species of organisms are descendants of ancestral species
- proposed a mechanism for the evolutionary process, natural selection
This greek philosopher viewed species as fixed and unchanging
Aristotle
He was interested in the ideal not in variation
Plato
Classification scheme. Scale naturae, lowest -> highest
Aristotle
Holds that species were individually designed by God and therefore perfect
Old testament Of bible
Turned away from the study of the natural world
Early christian church
This saint believed imperfect humans cant understand perfect creation
St augustine
Lack of scholarly work in the west meanwhile science was thriving in the islamic world
Dark ages
Revival of science an other scholarship
Renaissance
Inquiry into god’s creation idea that represents a great chain of being
St thomas aquinus
Studying nature to glorify god
Natural theology
Wrote the wisdom of God, manifested in the works of the creation; thought fossils represented undiscovered living species
John ray
Interpreted organismal adaptations as evidence that the creator had designed each species for a specific purpose; was a FOUNDER OF TAXONOMY, classifying life’s diversity “for the greater glory of God”
Carolus linnaeus
Small changes could occur through hybridization or _________
“acclimitization”
Discovery of rocks that resemble animal parts
Fossil record
Had microscopy studies showing that fossils closely resemble living form
Robert hooke
Geological layers correspond with age
Law of superposition
Helped lay ground work for darwin’s ideas
Study of fossils
remains or traces of organisms from the past; usually found in sedimentary rock, which appears in layers or strata
Fossils
Paleontologist and comparative anatomist who established extinction as a fact and suggested extinctions were caused by periodic global catastrophes
Georges Cuvier
Idea that profound change can take place through the cumulative effect of slow but continuous processes
Gradualism
They perceived that changes in earth’s surface can result from slow continuous actions
Geologists Hutton and Lyell
Wrote an encyclopedia of nature; suggested that species could degenerate in to other species
Leclerc comte de buffon
Buffon’s evidences
Similarity in limb structure of mammals and between related species
Charles’s grandfather; suggested that life evolved from a common ancestor
Erasmus darwin
Erasmus darwin’s evidences
Homology, artificial selection of domestic breeds
A vertebrate morphologist who believed that form dictates function (archetype)
Etienne Geoffroy - St. Hilaire
Evidence of St Hilaire
Homologous structures, vestigial traits, embryonic changes
Strong advocate of evolution; hypothesized that species evolved through use and disuse and inheritance of traits
Jean baptiste lamarck
Darwin proposed that species change through ________
Natural selection
The ship Darwin took to go to Galapagos
Beagle
He developed a theory of natural selection similar to darwin’s; sent darwin a manuscript
Alfred russell wallace
Darwin’s two main ideas
Evolution explains life’s unity and diversity; natural selection is a cause of adaptive evolution
This phrase summarized darwin’s perception of the unity of life; states that all organisms are related through descent
Descent with modification
Meaning of descent
Common ancestry, homology, relation, biogeography
What does modification denote
Change over time, vestigial traits, selective breeding, direct observation, fossil
What did darwin observe in galapagos
Marine iguanas, land tortoises, finches
Humans have selected plant and animal traits which benefit mankind; examples
Artificial selection; dog domestication, increase crop yield
Ability to pass on genes
Survival of the fittest
Force that drives evolution; individuals better adapted survive and leave more offspring; process by which individual organisms with favorable traits survive and reproduce
Natural selection
Components of natural selection
variation; differential reproduction; heredity
Mechanism for evolution
Variation
These are the environmental issues and illnesses that compose natural selection
Differential reproduction
Brown beetles that are left will mate and have brown offsprig
Heredity
Examples of natural selection
Orchid fool wasps, nonpoisonous snakes mimic poisonous snakes, katydids camouflage leaves
Factors of natural selection
Gene pool must vary (from mutation, immigration and emigration), variety must be inheritable, there must be competition
Evidence of evolution
Fossils (most direct evidence) , similar dna sequences (molecular level- gene and protein comparisons), homologous organs (similar in structure, diff in function), embryology
4 forces of evolutionary change
Genetic drift, gene flow, mutation, natural selection
Genetically based differences in survival or reproduction that leads to genetic change in population
Natural selection
Spontaneous changes in dna; results of mistakes
Mutations
Movement of genes between populations
Gene flow
Random changes in gene frequency
Genetic drift
Modes of natural selection
Stabilizing selection, directional selection, diversifying selection
Eliminates extreme phenotypes
Stabilizing selection
Shifts average in one dyrection by favoring one of the extreme phenotypes; anagenesis
Directional selection
Splits a population into 2 parts favoring both extremes ; cladogenesis
Diversifying selection
