There is an island in the middle of a large river that houses a large population of ants. Damming of the river causes the island to flood and only the highest points of the island are now above water. The ants cannot swim, so are now in multiple isolated populations. Which of the following best describes this event?A. isolation by dispersalB. isolation by vicarianceC. a form of sympatric speciationD. only a rare development of polyploidy could lead to speciation in this caseE. speciation will not occur in this case because of gene flow