Natural SelectionThe title of Darwins evolutionary biology book in1859 was:On the Origin of Species by Means of NaturalSelection, or the Preservation of Favoured Races inthe Struggle for Life
Natural SelectionDarwin suggested that Natural Selection is themechanism of evolution.
Think. Pair. Share.What is happening in this picture?
Natural SelectionNatural selection is the favouring of a trait that isbest suited for survival in its environment.
Natural SelectionThese traits arise from mutations. (Is this real?)
Natural SelectionMany different traits within a species is calledvariation, and these variations are heritable.
Natural SelectionDepending on the environment, different traits froma variety of species are more viable.
Natural SelectionFor example:•There is a population of mice living in a parking lot.Some are white and some are grey.•When a predator flies over the parking lot, it will eatthe first mouse it sees.
Natural SelectionFor example:•Since the grey mice are more difficult to see on theconcrete, white mice will be eaten more often thangrey mice.•Nature has selected the grey fur allele for survival inthis case.•The white fur allele may eventually die out in theparking lot population.