evolution 2 dr. james. whitfield, ph.d. hardy-weinberg equilibrium five factors are known to effect...
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Evolution 2Evolution 2Dr. James . Whitfield, Ph.D
Hardy-Weinberg Hardy-Weinberg EquilibriumEquilibriumFive Factors are known to effect
HWE, these include
Hardy-Weinberg Hardy-Weinberg EquilibriumEquilibriumFive Factors are known to effect
HWE, these includeGene migration or gene flow
Hardy-Weinberg Hardy-Weinberg EquilibriumEquilibriumFive Factors are known to effect
HWE, these includeGene migration or gene flowGenetic drift
Hardy-Weinberg Hardy-Weinberg EquilibriumEquilibriumFive Factors are known to effect
HWE, these includeGene migration or gene flowGenetic driftMutation
Hardy-Weinberg Hardy-Weinberg EquilibriumEquilibriumFive Factors are known to effect
HWE, these includeGene migration or gene flowGenetic driftMutationGenetic recombination
Hardy-Weinberg Hardy-Weinberg EquilibriumEquilibriumFive Factors are known to effect
HWE, these includeGene migration or gene flowGenetic driftMutationGenetic recombinationNatural selection
Founder EffectFounder EffectThe founder effect can result if
genes/alleles migrate from one population to another. Genes are lost in the original and added to the new population. If this migration happens multiple times it is called gene flow. If the same changes occur by chance it is called genetic drift. In any of these cases if the change is substantial enough speciation may occur and these individuals will become the founders of future generations
Founder EffectFounder EffectThe founder effect can also occur
as a result of a genetic bottleneck. A bottleneck can occur after a natural disaster or a severe disease that wipes out a significant percentage of the population. The surviving population may not represent the same genetic make-up as the original population hence the survivors become the founders of the new population
Founder EffectFounder EffectThe founder effect can also result
as a consequence of natural selection. Given enough time natural selection coupled with gene flow, variation due to recombination of genes, gene flow and genetic drift can all lead to speciation. Three different types of populations may occur, they are referred to as
StabilizingStabilizingStabilizing – in stabilizing
selection the average is favored and the extremes are tightened (less favorable) genetic diversity is decreased
Robin eggs and human baby weight, spider size
DirectionalDirectionalDirectional – in directional
selection both extremes are favored but at different times
Bird beaks, peppered moth
DisruptiveDisruptiveDisruptive – In disruptive
selection both extremes are favored at the same time. It is not good to be average. Two distinct populations form
Sea spongesRabbits