The first mammals evolved during the Late Triassic, but resembled reptiles.
This chapter emphasizes the raid evolution and diversification of mammals.
Angiosperms took over the land plant world during the Cenozoic.
Modern families of birds showed up early in the Cenozoic.
Because there has been less erosion, more Cenozoic fossils are found.
 

Corals became dominant reef builders during the Cenozoic.

Plants during the Cenozoic are similar to ones we have today,
but their distributions were different due to changing  climates (ex.  palms in Colorado)
 

55 million years ago a n abrupt heating event: PALEOCENE-EOCENE Thermal Maximum
Subtropical conditions all the way to Oregon and Wyoming.
 

Temperatures dropped rapidly at end of Eocene.
Gradual decrease in rainfall during the last 25 million years in N. America.

A large, predatory, flightless bird, DIATRYMA (7 ft) lived in N. America and Europe.
 

With the disappearance of dinosaurs, mammals quickly evolved and
diversified during the Cenozoic. Figure  18.7
Two major groups of MAMMALS:
      PROTOTHERIA ...MONOTREMES (Platypus and Spiny Anteater)
      THeria...MARSUPIALS (Kangaroo, Wallabies, Opossums, etc)
                    PLACENTALS (Horses, Bears, Dogs, Humans, etc..)
 

Paleocene...small mammals ( Fig.18.8)
Many orders of mammals that appeared during the Paleocene have died out.
Orders of mammals that showed up during Eocene are mostly still here.
*Look up UINTATHERES, ARSINOITHERIUM, and CHALICOTHERES**

About 4000 species of mammals still exist.

Fig. 18.11..largest rodent  PHOBEROMYS (700 kg)
Page 382 We saw the video Ashfall Fossil Beds-Nebraska
 

PRIMATES: lemurs, tarsiers present during the Eocene;
Oligocene New World and Old World Monkeys were present.
(Hominids present during the Miocene)

Strange:  hyenas are more closely related to cats than to dogs.
                  seals, walruses are related to bears

Hoofed mammals: Fig.18.14, 5 toes down to 1, 2, 3 or 4
 

Fig.18.15 note OREODONTS  (I'll bring in skull) Fig.18.17
 

MASTODON vs. MAMMOTH...difference is in the chewing teeth.
Horses evolved in N. America (Fig. 18.16b) but were gone until reintroduced by the Spaniards.

Whales...read student paper on the evolution of the whales.
 

During the Pleistocene: N.America...horses. mammoths, mastodons, saber-toothed cats,
giant beaver, GIANT GROUND SLOTH, GLYPTODONTS
About 14,000 years ago..many extinctions started
 

Last note:  When N.America and S.America connected, placental animals moved South
and some Marsupials moved North.  Most marsupials died out (except in Australia).