"If pressures change so that those with below average beak size gain some advantage than they can exploit it instantly . From the word go they will be eating better and be more healthy than their big beaked cousins , and so more likely to breed successfully come next breeding season ."
"Again , true . But that does n't take into account that there are two populations under consideration ."
"and so more likely to breed successfully come"
"Again , true ."