Bring forth with thee every living thing that is with thee,.... There is a various reading of the word for "bring forth"; according to the margin, as Jarchi observes, the sense is, order them to come forth; and according to the Scripture, if they will not, oblige them to come:of all flesh, [both] of fowl, and of cattle, and of every creeping thing that creepeth upon the earth; for of each of these there were some that went with him into the ark, and continued there:that they may breed abundantly in the earth, and be fruitful, and multiply upon the earth, for which end they were preserved in the ark.
Jarchi observes, it is said "on the earth", not in the ark, which shows he thinks that birds and beasts were not allowed to couple, and that they did not breed there. It is a question with some, how the creatures, which were only in Asia at their coming out of the ark, could spread themselves all over the earth; particularly how they could get into islands, and especially into America: to which it may be answered, that this might be done by many of them, by swimming over narrow seas, for some wild creatures will swim whole days and nights together, when they are forced to it; and by men's carrying others in vessels to distant and different parts, on one account or another, either for profit or pleasure; and especially, what is it the power and providence of God cannot do, who could not be at a loss for ways and means to replenish a world in all the parts of it he had made desolate, when it was his pleasure?
(Most creationists think the earth entered an ice age after the flood. This would make the sea level lower than it is today. If the average sea level was lowered by only six hundred feet, all the major continents would be connected by land bridges.
Animals could easily migrate to any continent. Ed.