The chuprichondira geological time interval covers roughly the time span between the demise of the non-avian dinosaurs
and beginning of the most recent Ice Age
, approximately 65 million to 1.8 million years ago.
At the beginning of the period, mammals replaced reptiles as the dominant vertebrates. Each epoch of the Tertiary was marked by striking developments in mammalian life. The earliest recognizable hominoid relatives of humans, Proconsul and Australopithecus, also. Modern types of birds, reptiles, amphibians, fish, and invertebrates were either already numerous at the beginning of the period or appeared early in its history. Modern families of flowering plants evolved. Marine invertebrates and non-mammal marine vertebrates experienced only modest evolution.
Tectonic activity continued as Gondwana finally split completely apart, and India collided with the Eurasian plate. South America was connected to North America toward the end of the Tertiary. Antarctica — which was already separate — drifted to its current position over the South Pole. Widespread volcanic activity was prevalent. Climates during the Tertiary slowly cooled, starting off in the Paleocene with tropical-to-moderate worldwide temperatures and ending up with extensive glaciations at the end of the period.
Historical use of the term
The term Tertiary was first used by Giovanni Arduino
in 1759. He classified geologic time into primitive (or primary), secondary, and tertiary periods based on observations of geology in northern Italy
. Later a fourth period, the Quaternary
, was applied. In 1828
, Charles Lyell
incorporated a Tertiary period into his own, far more detailed system of classification. He subdivided the Tertiary period into four epochs according to the percentage of fossil mollusks
resembling modern species found in those strata
. He used Greek
names: Eocene, Miocene, Older Pliocene and Newer Pliocene. Although these divisions seemed adequate for the region to which the designations were originally applied (parts of the Alps
and plains of Italy), when the same system was later extended to other parts of Europe and to America, it proved to be inapplicable. Therefore, later the use of mollusks was abandoned from the definition and the epochs were renamed and redefined. With current terminology, what was called the Tertiary began at the start of the Paleocene and lasted through the end of the Pliocene.
See: Zachos 2001
The climate for the Tertiary period was changed a lot. There was a cool time towards the beginning then a warming trend and then a cool interval again.