The process of biological change by which descendants come to differ from their ancestors
Linnaeus ideas
Developed a classification system for all organisms known at that time. Proposed that organisms could have arisen through hybridization.
Buffon ideas
Species shared ancestors instead of arising separately. Rejected idea that earth was only 6,000 years old.
Erasmus Darwin
All living things were descended from a common ancestor and complex forms of life came from simpler forms of life.
Lamarck ideas
Organisms evolved towards perfection and complexity. Species must have evolved into different forms instead of becoming extinct. Changes in an environment caused an organisms behavior to change, causing disuse of structures. Giraffes.
Species
Group of organisms so similar to one another that they can reproduce and have fertile offspring
Fossils
Traces of organisms that existed in the past. Cuvier
Catastrophism
Natural disasters such as floods and volcanic eruptions have happened often during Earth's long history. Cuvier
Gradualism
Changes in landforms resulted from slow changes over a long period of time. Hutton
Unformitarianism
Geological processes that shape Earth are uniform through time.
Variation
Difference in physical traits of an individual from those of other individuals in the group that it belongs.
Adaptation
A feature that allows an organism to better survive in its environment
Artificial Selection
The process by which humans change a species by breeding it for certain traits
Heritability
The ability of a trait to be passed down from one generation to the next
Natural Selection
A mechanism by which individuals that have inherited beneficial adaptations produce more offspring on average than do other individuals.
Population
All the individuals of a species that live in an area
Four main principles of natural selection
Variation
Overproduction
Adaptation
Descent with modification (same traits in population)
Fitness
The measure of the ability to survive and produce more offspring relative to the other members of the population in a given environment
Biogeography
The study of the distribution of organisms around the world
Homologous Structures
Features that are similar in structure but appear in different organisms and have different functions.
Analogous Structures
Structures that perform a similar function but are not similar in origin.
Vestigial Structures
Remnants of organs or structures that had a function in an early ancestor.
Paleontology
The study of fossils or extinct organisms that continues to provide new information and support current hypothesis about how evolution occurs
Homeobox Genes
Genes that control the development of specific structures. Found in almost every organism, suggest a common ancestry
Pseudogenes
sequences of DNA nucleotides that no longer function but are still carried along. They can change as they are passed down through generations.
Proteins
cells from different species that have the same proteins most likely come from a common ancestor.
Reproductive isolation
Occurs when members of different populations can no longer mate succesfully with one another.
Speciation
The rise of two or more species from one existing species
Behavioral isolation
Isolation caused by differences in courtship or mating behaviours
Geographical Isolation
Involves physical barriers that divide a population into two or more groups.
Temporal isolation
Exists when timing prevents reproduction between populations
Convergent evolution
Evolution towards similar characteristics in unrelated species
Divergent evolution
When closely related species evolve in different directions
Coevolution
the process in which two or more species evolve in response to changes in eachother
Extinction
The elimination of a species from Earth
Punctuated equilibrium
Episodes of speciation occur suddenly in geological time and are followed by long periods of little evolutionary change
Adaptive radiation
The diversification of one ancestral species into many descendent species