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Mesozoic era

(Encyclopedia)Mesozoic era mĕzˌəzōˈĭk [key] [Gr.,=middle life], major division of geologic time (see Geologic Timescale, tablegeologic timescale, table) from 65 to 225 million years ago. Great crustal disturb...

Cenozoic era

(Encyclopedia)Cenozoic era sēnəzōˈĭk, sĕn– [key], last major division of geologic time (see Geologic Timescale, tablegeologic timescale, table) lasting from 65 million years ago to the present. The Cenozoic...

era

(Encyclopedia)era, period of historic time. In geology, it is the name applied to large divisions of geological process, e.g., Paleozoic era (see geology). In chronology an era is a period reckoned from a fixed poi...

Paleozoic era

(Encyclopedia)Paleozoic era pāˌlēəzōˈĭk [key], a major division (era) of geologic time (see Geologic Timescale, tablegeologic timescale, table) occurring between 570 to 240 million years ago. It is subdivide...

Paleocene epoch

(Encyclopedia)Paleocene epoch pāˈlēəsēnˌ [key], first epoch of the Tertiary period in the Cenozoic era of geologic time (see geologic timescale) between 60 to 66 million years ago. In W North America, the upl...

era of good feelings

(Encyclopedia)era of good feelings, period in U.S. history (1817–23) when, the Federalist party having declined, there was little open party feeling. After the War of 1812 all sections were anxious to return to a...

ammonite

(Encyclopedia)ammonite ămˈənīt [key], one of a type of extinct marine cephalopod mollusk, related to the nautilus and resembling it in having an elaborately coiled and chambered shell. Unlike the interiors of n...

mammal

(Encyclopedia)mammal, an animal of the highest class of vertebrates, the Mammalia. The female has mammary glands, which secrete milk for the nourishment of the young after birth. In the majority of mammals the body...

Reconstruction Era National Historical Park

(Encyclopedia)Reconstruction Era National Historical Park: see National Parks and Monuments (table)national parks and monuments (table). ...

Geologic Timescale (table)

(Encyclopedia)Geologic Timescale 1 Not an era but the time preceding the Cambrian. ...