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F.C. Whitmore

Publications and source records attributed to F.C. Whitmore.

7 recordsLinked to original sources
USGS2000

Endocranial volume of mid-late eocene archaeocetes (order: cetacea) revealed by computed tomography: Implications for cetacean brain evolution

The large brain of modern cetaceans has engendered much hypothesizing about both the intelligence of cetaceans (dolphins, whales, and porpoises) and the factors related to the evolution of such large brains. Despite much interest in cetacean brain evolution, until recently there have been few estimates of brain mass and/or brain–body weight ratios in fossil cetaceans. In the present study, computed tomography (CT) was used to visualize and estimate endocranial volume, as well as to calculate level of encephalization, for two fully aquatic mid-late Eocene archaeocete species, Dorudon atrox and Zygorhiza kochii. The specific objective was to address more accurately and more conclusively the question of whether relative brain size in fully aquatic archaeocetes was greater than that of their hypothesized sister taxon Mesonychia. The findings suggest that there was no increase in encephalization between Mesonychia and these archaeocete species.

Journal of Mammalian Evolution↗
USGS1967

Elephant teeth from the Atlantic Continental Shelf

Teeth of mastodons and mastodons have been recovered by fishermen from at least 40 sites on the continental shelf as deep as 120 meters. Also present are submerged shorelines, peat deposits, lagoonal shells, and relict sands. Evidently elephants and other large mammals ranged this region during the glacial stage of low sea level of the last 25.000 years.

Science↗
USGS1965

Miocene mammals and Central American seaways

The presence of Miocene mammals of North American affinity in the Panama Canal Zone indicates that Central America was attached to North America. That this attachment was a broad and stable land mass is shown by the close relation of the Panama Miocene herbivores to the widely distributed Miocene herbivore fauna of North America. A continuous connection existed probably throughout the Tertiary, to the west and north of the isthmian region, but the tectonically active isthmus probably was broken up into an archipelago during most of Tertiary time. Between the islands ran the Strait of Panama; from time to time parts of the isthmian area were connected to the stable land to the west, allowing eastward migration of land animals. The mammals of North American affinity in the Cucaracha Formation were found only a few kilometers from the western end of the San Blas Area, a stable land mass in eastern Panama that was separated from South America by the Bolivar Trough during most of the interval between Oligocene and Pliocene time. The Strait of Panama was a less stable barrier than the Bolivar Trough; this being so, it is likely that the San Blas Area was inhabited by land animals of North American rather than South American affinity. Thus, the disappearance of the Bolivar seaway in Pliocene time would have allowed, probably for the first time, mingling of the North and South American mammal faunas.

Panama Canal↗