Why are the trilobites from Oklahoma and Morocco so similar?
One interesting example of trilobite paleogeography involves the Devonian trilobite sites of Oklahoma (such as the famous Haragan Formation), and those of Morocco (such as the prolific Hamar Laghdad Formation of the Atlas Mountains). Although on different continents today (as well as different paleocontinental systems during the Devonian), the similarities of the taxa from the two regions are amazing. Here, for example, are three of the parallel developments between the Oklahoma trilobite assemblage (top) and that of Morocco (bottom). In some cases, the same genera are found in both locations.
