Term | Definition |
Natural Selection | The process that results in living things with beneficial traits producing more offspring than others. Changes the traits of living things over time. |
Jean Baptiste Lamarck (1744-1829) | Argued that species change over time. His idea of inheritance of acquired characteristics is incorrect. Traits an organism develops during its own lifetime cannot be passed on to an offspring. |
Charles Lyell (1797-1875) | Argued that gradual geological processes have gradually shaped Earth's surface. He believes Earth is older than most people believe. |
Thomas Malthus (1766-1834) | Argued that human populations grow faster than the resources they depend on. When populations become too large, famine and disease break out. |
Artificial Selection | The breeding of plants or animals desirable traits. The opposite is called natural selection. |
Alfred Russel Wallace | English naturalist that traveled places to study the environment and had the same theory as Darwin. |
Charles Darwin | Creator of evolution. |
Paleontologists | Scientists who find and study fossils. |
Comparative Anatomy | The study of similarities and differences in the structures of different species. |
Homologous Chromosomes | Structures that are similar in related organisms because they were inherited from a common ancestor. |
Analogous | Structures that are similar in unrelated organisms because they evolved to do the same job, not because they were inherited from a common ancestor. |
Comparative Embryology | The study of the similarities and differences in the embryos of different species. Similarities is the evidence of common ancestry. |
Vestigial Structure | Evolution has reduced their size because the structures no longer used. |
Biogeography | The study of how and why plants and animals live where they do. |
Microevolution | Occurs over a relatively short period of time within a population or species. |
Genotype | Genetic makeup of an individual. |
Gene Pool | A population that consists of many genotypes. |
Allele Frequency | The amount of times the allele occurs in a gene pool relative to the other alleles for that gene. |
Evolution Occurring | Occurs in a population when allele frequencies change over time. |
The Hardy- Weinberg Theory | Shows that allele frequencies do not change in a population if certain conditions are met. |
Forces of Evolution | Mutation, gene flow, genetic drift, and natural selection. |
Mutation | Creates a new genetic variation in a gene pool. |
Gene Flow | Occurs when individuals move into or out of a population. |
Genetic Drift | A random change in allele frequencies that occurs in a small population. |
Bottleneck Effect | Occurs when a population suddenly gets much smaller. |
Founder Effect | Occurs when a few individual start, or found, a new population. |
"Fit for the environment" | Organisms that are better adapted to the environment. |
Polygenic Traits | Stabilizing selection, directional selection, distributive selection. |
Stabilizing selection | Occurs when phenotypes at both extremes of the phenotypic distribution are selected against. |
Directional Selection | Occurs when one of the two extreme phenotype is selected for. |
Distributive Selection | Occurs when phenotypes in the middle of the range are selected against. |
Macroevolution | Occurs over geologic time above the level of the species. |
Speciation | Process by which a new species evolves. |
Allopatric Speciation | Species that are unable to interbreed. |
Sympatric Speciation | New species arises without geographic separation |
Coevolution | When species in symbiotic relationships evolve together. |
Gradualism | Occurs gradually due to stable geologic and climate conditions. |
Punctuated Equilibrium | Occurs rapidly because of geologic and climate conditions changing |