| rdfs:comment | - The ancestors of the dinoceratopsians, primitive cenoceratopsians similar to the dawnhorns, crossed from Asia to North America some time during the early Neogene (or possibly as early as the Oligocene), and in the late Miocene and Pliocene, they diversified into a host of huge and bizarre forms. These creatures, however, soon faced the fate of most of their earlier cousins, the ceratopsids, as North America cooled and the open deciduous forests ceratopsians prefer were replaced with inhospitable grasslands. Hadrosaurs and therizinosaurs spread to take advantage of the new Ice Age habitats, but North American ceratopsians were forced to migrate southward. In some places, the dinoceratopsids held on, and it now seems that a single species has survived in southern Florida, with rumors persist
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| abstract | - The ancestors of the dinoceratopsians, primitive cenoceratopsians similar to the dawnhorns, crossed from Asia to North America some time during the early Neogene (or possibly as early as the Oligocene), and in the late Miocene and Pliocene, they diversified into a host of huge and bizarre forms. These creatures, however, soon faced the fate of most of their earlier cousins, the ceratopsids, as North America cooled and the open deciduous forests ceratopsians prefer were replaced with inhospitable grasslands. Hadrosaurs and therizinosaurs spread to take advantage of the new Ice Age habitats, but North American ceratopsians were forced to migrate southward. In some places, the dinoceratopsids held on, and it now seems that a single species has survived in southern Florida, with rumors persisting of similar creatures in the swamps of Louisiana. Dinoceratopsia escaped oblivion, however, as some populations migrated past the dubious havens of Louisiana and Florida. As early as the Pliocene, populations of dinoceratopsians migrated across the Panama Isthmus and established themselves in South America. There were at least two distinct migrations, the early dinoceratopsids (today represented by a single species) and more advanced jugaloceratopsids (including the everglades tuskhorn). The enigmatic 'durocephalids' may represent another migration (possibly earlier than the jugaloceratopsids), or may have evolved in South America.
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