User:Abyssal/Portal:Quaternary

Portal topics: Activities; Culture; Geography; Health; History; Mathematics; Nature; People; Philosophy; Religion; Society; Technology; Random portal

The Quaternary prehistory Portal

Introduction

The Quaternary (/kwəˈtɜːrnəri, ˈkwɒtərnɛri/ kwə-TUR-nə-ree, KWOT-ər-nerr-ee) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the Phanerozoic eon. It follows the Neogene Period and spans from 2.58 million years ago to the present. The Quaternary Period is divided into two epochs: the Pleistocene (2.58 million years ago to 11.7 thousand years ago) and the Holocene (11.7 thousand years ago to today); a proposed third epoch, the Anthropocene, was rejected in 2024 by IUGS, the governing body of the ICS.

The Quaternary is typically defined by the Quaternary glaciation, the cyclic growth and decay of continental ice sheets related to the Milankovitch cycles and the associated climate and environmental changes that they caused. (Full article...)

Show new selections below (purge)

edit

Selected article on the Quaternary prehistory world and its legacies

The evolutionary history of life on Earth traces the processes by which living and fossil organisms have evolved since life on the planet first originated until the present day. Earth formed about 4.5 Ga (billion years ago) and life appeared on its surface within one billion years. Microbial mats of coexisting bacteria and archaea were the dominant form of life in the early Archean. The evolution of oxygenic photosynthesis, around 3.5 Ga, eventually led to the oxygenation of the atmosphere, beginning around 2.4 Ga. The earliest evidence of eukaryotes (complex cells with organelles), dates from 1.85 Ga, and while they may have been present earlier, their diversification accelerated when they started using oxygen in their metabolism. Later, around 1.7 Ga, multicellular organisms began to appear, with differentiated cells performing specialised functions.

The earliest land plants date back to around 450 Ma (million years ago), although evidence suggests that algal scum formed on the land as early as 1.2 Ga. Land plants were so successful that they are thought to have contributed to the late Devonian extinction event. Invertebrate animals appear during the Vendian period, while vertebrates originated about525 Ma during the Cambrian explosion. During the Permian period, synapsids, including the ancestors of mammals, dominated the land, but the Permian–Triassic extinction event251 Ma came close to wiping out all complex life. (see more...)

More articles...

edit

Selected article on the Quaternary prehistory in human science, culture and economics

Edward Drinker Cope (left) and Othniel Charles Marsh (right).

Bone Sharps, Cowboys, and Thunder Lizards: A Tale of Edward Drinker Cope, Othniel Charles Marsh, and the Gilded Age of Paleontology (2005) is a graphic novel written by Jim Ottaviani and illustrated by the company Big Time Attic. The book tells a slightly fictionalized account of the Bone Wars, a period of intense excavation, speculation, and rivalry which led to a greater understanding of dinosaurs in the western United States. This novel is the first semi-fictional work written by Ottaviani; previously, he had taken no creative license with the characters he depicted, portraying them strictly according to historical sources.

Bone Sharps follows the two scientists Edward Drinker Cope and Othniel Marsh as they engage in an intense rivalry for prestige. Ottaviani has Cope and Marsh interact and meet many important figures of the Gilded Age, from P. T. Barnum to U.S. Grant, as the two scientists pursue their hotheaded and sometimes illegal acquisitions of fossils. Unlike in his previous books, "the scientists are the bad guys this time". Upon release, the novel received praise from critics for its exceptional historical content, although some reviewers wished more fiction had been woven into the story. (see more...)

More articles...

edit

Selected image

Sir Richard Owen and a Dinornis skeleton.
Photo credit: John van Voorst

More pictures...

edit

Did you know?

... that the New Zealand and the Chatham Coot were likely hunted to extinction by the Māori people?
... that Archaeoindris (pictured), a recently extinct giant lemur from Madagascar, was the largest known lemur, comparable in size to a male gorilla?
... that fossils of Eucommia constans are the youngest and most southerly examples of Eucommia in North America?
... that French paleontologist Charles Lamberton scathingly rebutted a theory claiming that some extinct, giant lemurs were aquatic and that one of them was an "arboreal-aquatic acrobat"?
... that the broad-fronted moose was probably the largest species of deer that has ever existed?