Carolus Linneaus
The scientist who developed a classification system for living things
Georges Louis Leclerc de Buffon
The scientist who proposed species shared ancestors
Erasmus Darwin
The scientist who proposed all living things descended from a common ancestor
Jean-Baptiste Lamarck
The scientist who proposed a theory that all organisms evolved toward perfection and complexity
James Hutton
The scientist who proposed that Earth was very old, saying geologic change occurred gradually & at a constant rate
Charles Lyell
The scientist who published “Principles of Geology”
6000
For a long time, people believed the Earth was only ____ years old
Galapagos Islands
The place Darwin did his studies
Adapted to their surroundings
Darwin discovered animals did this
Variations
Differences in physical traits, like those Darwin observed between animals in different locations
Artificial Selection
The process by which humans change a species by breeding it for certain traits
Natural Selection
The process by which the environment influences evolution
Fitness
An organism’s ability to survive
Variation, Overproduction, Adaptation, & Descent with Modification
The 4 main factors necessary for natural selection
Phenotype
Natural selection acts on _______
Fossils, Geography, Embryology & Anatomy
4 pieces of evidence for evolution
Embryology
The observation of similarities in embryos among animal species
resembled
Darwin found finches on Galapagos Islands ______ those found on the mainland, with a few adaptations
Homologous Structures
Features in different animals similar in structure but with different functions
Analogous Structures
Structures that perform similar functions but that aren’t similar in origin
Vestigial Structures
Structures or organs seemingly lacking in function, left over from previous ancestors
Pseudogenes
Genes left over from ancestors that no longer function
DNA Sequence Analysis
Based on _____________, more closely related organisms have more similar DNA
Gene Pool
Genetic variation stored in populations
Allele Frequency
The percentage of organisms in a population with a certain allele
Mutations & Recombination
2 sources of genetic variation
Mutations
Random change in an organism’s DNA that can form new traits
Recombination
A new allele combination showing up in offspring, most frequently happening during meiosis
Normal Distribution
Distribution of a trait resembling a bell curve
Microevolution
An observable change in allele frequency of a population over time
Directional Selection
A shift in population’s phenotypic distribution. For instance, an extreme phenotype that was once rare is now common
Stabilizing Selection
The intermediate phenotype is favored and becomes more common, decreasing genetic diversity
Disruptive Selection
Both extreme phenotypes are favored, possibly leading to formation of new species
Gene Flow
The movement of alleles between populations
Similar
Gene flow between populations keeps gene pools ______
Genetic Drift
A change in allele frequencies by chance
Bottleneck Effect & Founder Effect
2 ways genetic drift occurs
Bottleneck Effect
Genetic drift occurring after an event that kills much of the population
Founders Effect
Genetic drift occurring after a small number of individuals colonize a new area
Loss of genetic variation & possible increase in lethal alleles
Effects of genetic drift
Sexual Selection
The effect of traits increasing mating success
Hardy-Weinberg Equilibrium
Populations that are not evolving
Large populations, no migration, no mutations, random mating, and no natural selection
Conditions for populations that aren’t evolving
Speciation
The rise of 2 or more species from one existing species`
Reproductive, Behavioral, Temporal, or Geographic Isolation
Reasons for speciation
Reproductive Isolation
When members of the same species can no longer successfully mate
Behavioral Isolation
Differences in courtship or mating behavior stopping individuals of a species from mating
Geographic Isolation
Geographic barriers preventing members of a species from mating
Temporal Isolation
Timing preventing members of a species from mating
They’re unable to mate
What makes one species split into 2?
Convergent Evolution
Evolution when unrelated species become more similar
Divergent Evolution
Evolution when related species begin to differ
Coevolution
2 or more species evolving in response to changes in the other
Extinction
Elimination of a species from Earth
Punctuated Equilibrium
Bursts of evolutionary activity
Adaptive Radiation
Diversification of one species into many descendant species