The five orders grouped together here are of African origin and all closely related.
The Hyracoidea are rodent-like in size and appearance. The remaining four orders all share
a tendency toward large, heavy sizes. The Embrithopoda are known mainly from the Oligocene Fayum deposits of Egypt.
The Proboscidea are the largest and most diverse order in this group; they include the
ancestral moeritheres, the dinotheres, the barytheres, and the Euelephantida, a clade
that includes mastodonts, stegodonts, mammoths, and elephants. Most Proboscidea are extinct;
only two living genera remain. Throughout their evolution, the Proboscidea have possessed
defensive tusks derived from the incisor teeth. In an early evolutionary trend, the jaws
became longer, but the trend later reversed and the jaws became shorter and the teeth fewer
and more specialized to retain their grinding surfaces over an increasing lifespan.
Two aquatic orders, the Sirenia and Desmostylia, are related to the Proboscidea.
Cenozoic climates were generally warmer than they are currently. Continents were
mostly in their modern positions, but South America was an island continent (like Australia)
until the end of the Pliocene. Sporadic migrations were possible at high latitudes between the Americas
and Eurasia during the Tertiary. During the Pleistocene, lower sea levels made the Bering and Panama land bridges available
for widespread migrations between North and South America and between North America and Eurasia.
- African origins
- Order Hyracoidea
- Order Embrithopoda
- Order Proboscidea
- Moeritheres
- Trends among the Proboscidea
- Deinotheria
- Barytheria
- Euelephantida
- Long-jawed mastodonts (Gomphotherioidea)
- Crested-tooth mastodonts (Mastodontoidea)
- Stegodonts (Stegodontoidea)
- Elephants and mammoths (Elephantoidea)
- Order Sirenia
- Order Desmostylia
Illustrations
- Cenozoic continents and faunas
- Cenozoic continents
- Cenozoic climates
- Intercontinental migrations
- Pleistocene glaciations and sea level changes
- Paleontology research around the world
- A model for the post-colonial history of science:
- 1st generation: research by European (and North American) visitors
- 2nd generation: research by indigenous scientists trained in Europe or North America
- 3rd generation: research by indigenous scientists trained in their home country
- Paleontology in Europe and Africa
- Paleontology in the Americas
- Paleontology in Asia (e.g. Mongolia)
- Is China a special case?
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