A period of very low rainfall occurred while the Grants were on the islands. The drought resulted in fewer seeds for the finches to eat. Birds with smaller beaks could eat only the smaller seeds. Birds with bigger beaks were better off. They could eat seeds of all sizes. Therefore, there was more food available to them. Many of the small-beaked birds died in the drought. More of the big-beaked birds survived and reproduced. Within just a couple of years, the average beak size in the finches increased. This was clearly evolution by natural selection.
Two ancient continents both had a great bird population. At some point in time, the continent of MU experienced a great drought that lasted for several years. The other continent, Lemuria, was unaffected by the drought.
Which continent had fewer seeds for the birds?