Final answer:
The listed terms represent periods of the geologic time scale, which is crucial for understanding Earth's history, the evolution of life, and geological events. The Paleozoic, Mesozoic, and Cenozoic eras are major subdivisions of this time scale.
Step-by-step explanation:
The terms Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Tertiary (Paleogene, Neogene), Quaternary all refer to different periods of the geologic time scale. This time scale is used by geologists and biologists to describe the timing and relationships of events in the Earth’s history. The division of time into eons, eras, periods, epochs, and ages helps scientists understand when different types of plants and animals existed, as well as the major geological and climatic events that have occurred.
The Paleozoic era is divided into six periods, starting with the Cambrian and followed by the Ordovician, Silurian, Devonian, Carboniferous (comprising the Mississippian and Pennsylvanian), and Permian. The Mesozoic era consists of the Triassic, Jurassic, and Cretaceous periods. Finally, the Cenozoic era includes the Tertiary period (which has been redefined into the Paleogene and Neogene periods) and the Quaternary period.
Geologists often use abbreviations when referring to these geological time units, such as "K" for Cretaceous and a C with a slash through it for Cambrian. The importance of this time scale is evident in studying the history of life, as it allows scientists to track evolutionary events and mass extinctions, like the Ordovician-Silurian, Devonian, Permian-Triassic, Triassic-Jurassic, and Cretaceous-Paleogene events.