Diversity

• Species:

  • Organisms that can successfully interbreed to produce viable and fertile offspring under natural conditions 
• Hybrid:

  • An individual produced by a cross between parents with different genotypes; often used to refer to the offspring of different varieties or species
• Viable:

  • An organism that is alive or capable of sustaining life
• Natural selection: Charles Darwin - 1858

  • Natural selection acts on the phenotypes of individuals so that some survive and reproduce while others do not. Through natural selection, favourable traits selected for are inherited and favourable alleles are passed onto the next generation
• Process of natural selection:

  
  

  V - Populations have variation between organisms (genetic diversity)

  E - Selection pressures (environmental factors and competition resources) act on populations

  S - Those individuals with the most suited phenotype or characteristic (best genetic build) are selected for, therefore survive and reproduce

  T - Over time, alleles of the ‘selected’ individuals are passed onto the next generation and therefore the population evolves
• Selective pressures:

  • The effect of the selective agent (an environmental factor that acts on a population during natural selection) on a population
• Artificial selection:

  • The process by which humans choose to breed particular organisms with desirable features 
  • Also known as selective breeding