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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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.
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.