We see the same fact in the great difference between the inhabitants of Australia, Africa, and South America under the same latitude; for these countries are almost as much isolated from each other as is possible.
Egitate bera ikusten dugu Australia, Afrika eta Hego Amerikako biztanleen artean latitude beretan dagoen eskualde handian ere, izan ere, herrialde hauek elkarrengandik ahal den isolatuenik daude eta.