APES unit 3

  1. Biological Evolution

    1. Organisms change from generation to generation through changes in their genetic material

  2. Gene pool

    1. Total collection of genes in a population

  3. Gradualism

    1. Evolution occurs through small incremental changes over a long period of time

  4. Punctuated Equilibrium

    1. Long periods of stability interrupted by brief periods of rapid change

  5. Microevolution

    1. Evolutionary changes within a species/small group of organisms usually over a short period of time

  6. Macroevolution

    1. Large-scale changes that result after the formation of a new species over a long period of time.

  7. Background Extinction

    1. Normal, low-level rate of extinction that occurs naturally throughout Earth’s history.

  8. Mass Extinction

    1. Widespread, rapid decrease in biodiversity

  9. Causes for Extinction

    1. HIPPO

  10. Founder Effect

    1. A small group of organisms establishes a new population with a different gene pool from the original population


  1. Bottleneck

    1. Sharp reduction in the size of a population sometimes caused by a natural disaster that drastically reduces the genetic diversity

  2. Artificial Selection

    1. Human-directed breeding to promote desirable traits

  3. Natural Selection

    1. Organisms with favorable traits are more likely to survive and reproduce

  4. Genetic Drift

    1. Random changes in the frequency of alleles, often in small populations, happens quickly

  5. Allopatric Speciation (Geographic Speciation)

    1. Speciation that occurs when a population is geographically isolated

  6. Sympatric Speciation (Behavioral Speciation)

    1. Occurs in the same geographical area, bu6t usually results from a change in behavior of ecological difference

  7.  Biodiversity

    1. The variety of life in a particular habitat or ecosystem

  8. Fitness

    1. The ability of an organism to survive and reproduce in its environment

  9. Causes of Mutations

    1. DNA Replication errors

    2. Exposure to radiation

    3. Chemicals

    4. Viruses

  10. Directional Selection

    1.  Favors one extreme

  11. Stabilizing Selection

    1. Favors the average individuals

  12. Disruptive Selection

    1. Favors both extremes

  13. Measuring Diversity

    1. Richness

      1. Number of species in a community 

      2. Qualitative

    2. Evenness

      1. How evenly the species is distributed in a community, abundance of individuals in each species

      2. Quantitative 

  14. Simpson’s Diversity Index

    1. Measure of diversity that accounts for both species richness and evenness

    2. D=1-[ (n/N)2]

  15. Endangered Species Act (Richard Nixon)

    1. Law aimed at prevented species from going extinct

  16. Alleles

    1. Different versions of a gene

  17. Invasive Species

    1. Non-native species that spread rapidly in a new environment, usually damaging it

  18. Biological Corridors

    1. Areas that connect different ecosystems, allowing species to migrate and maintain genetic diversity

  19. Island Biogeography

    1.  If an island is closer it will have higher biodiversity

    2. If an island is larger it will have higher biodiversity

  20. Endemic

    1. A species that is native to a specific geographic area and found nowhere else

  21. HIPPO

    1. Habitat destruction

    2. Invasive species

    3. Pollution 

    4. (human) Population

    5. OVerharvesting

  22. Error Bars

    1. If they overlap it is significant and if they don’t it is insignificant

  23. Lyme Disease

    1. A bacterial infection transmitted by ticks

  24. Coevolution

    1. Species influence each other’s evolution through close ecological interactions

  25. Divergent Evolution

    1. Two or more species share a common ancestor but continue to evolve and become less similar over time

  26. Convergent Evolution

    1. Unrelated species evolve to develop similar traits independently due to similar environmental pressures or ecological niches