Domain VEvolution

Origins of EvolutionJean Baptiste de Lamarck and Acquired CharacteristicsCharles DarwinCharles Lyells Principles of GeologyThomas Malthus called The Principles of Population40,000-mile trip on the Beagle

Galapagos IslandsWhat did he find there?Aquatic iguanasGiant Tortoises Species of finches

2 Themes EmergedVariations within a species were dependent on the environment.Organisms on the Galapagos Islands had become geographically separated resulting in reproductive isolation which leads to speciation.

Natural SelectionChanges in a population that occur when organisms with favorable variations for that particular environment survive, reproduce and pass these variations on to the next generation.

Darwins TheoryDecent with modification through natural selection.Environmental Challenges result in certain traits increasing the reproductive fitness of certain individuals within a species.

History of LifeTypes of EvolutionDivergent (Adaptive Radiation)ConvergentRates of EvolutionGradualismPunctuated Equilibrium

Types of Natural SelectionStabilizing SelectionDirectional SelectionDiversifying SelectionDisruptive SelectionBalancing Selection

Diversifying SelectionWhen a population is faced with conditions so diverse that no single phenotype is more successful that any other, genetic and phenotypic variability allow different selective pressures to operate at the same time.

Balancing Selection operates to counteract the loss of variant alleles in a population.Two forms of : heterozygote advantage and frequency-dependent selection.

BiodiversityResulted from divergent evolution.

Lines of EvidenceIncomplete Fossil Record >Relative Dating >Time Averaging >Radioisotope DatingBuilding a Phylogeny >Phylogenetic Tree

Mass ExtinctionsWere catastrophic events the cause of mass extinctions, did they happen quickly or did they occur over a long period of time?

If they occurred over a long period of time, why did the species not adapt to their changing environment in order to survive?

Biological ResistanceOysters in Malpeque BayInsect Resistance to InsecticidesViruses Gene Amplification