Industry that provides services rather than goods. Economists divide the products of all economic activity into two broad categories, goods and services. Industries that produce goods (tangible objects) include agriculture, mining, manufacturing, and construction. Service industries include everything else: banking, communications, wholesale and retail trade, all professional services such as engineering and medicine, all consumer services, and all government services. The proportion of the world economy devoted to services rose rapidly in the 20th century. In the U.S. alone, the service sector accounted for more than half the gross domestic product in 1929, two-thirds in 1978, and more than three-quarters in 1993. Worldwide, the service sector accounted for more than three-fifths of global gross domestic product by the early 21st century. As increases in automation facilitate productivity, a smaller workforce is able to produce more goods, and the service functions of distribution, management, finance, and sales become relatively more important.

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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.

Climate

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.

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