Kauffman (1977) has presented a model of Cretaceous paleogeography and paleoclimatology as the supercontinent of Pangea broke up and the Atlantic Ocean opened. A circum-equatorial ocean, the Tethys Seaway, dominated world paleogeography, stretching across the America, northern Africa, and southern Europe into the Paleo-Indian Ocean (where India was still a drifting subcontinent). Branching off this east-west ocean were several north-south epicontinental seaways including the Western Interior seaway and the Northern Atlantic Seaway, both stretching from the Tethys northward into the paleo-Arctic Ocean. The Western Interior Seaway was characteristically a shallow, epicontinental seaway, perhaps little more than a hundred meters deep while the northern Atlantic was a true oceanic area floored by oceanic crust extruded along the mid-Atlantic Ridge as the ocean basin opened by sea floor spreading. The Atlantic Ocean was certainly a deeper, more oceanic body of water less prone to the vagaries of local climate and tectonic activity. Within this setting the primitive decapods underwent several major adaptive radiations and formed the lineages leading to modern decapod faunas.