Explain how geographic isolation can affect
evolution.
need

Geographic isolation stops the exchange of genetic material between the two populations. ... Differences in climate and food sources can create selective pressures unique to each population. Eventually, the two populations might become different species, but not always.

the offspring would all be white. if the parents are both white flowers then they have the genotype rr, which when crossed results in an all white punnet square.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".