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Geologic time scale

Geologic time scale
The geologic time scale (GTS) is a system of chronological measurement that relates stratigraphy to time, and is used by geologists, paleontologists, and other earth scientists to describe the timing and relationships between events that have occurred throughout Earth's history. The table of geologic time spans presented here agrees with the nomenclature, dates and standard color codes set forth by the International Commission on Stratigraphy. Evidence from radiometric dating indicates that the Earth is about 4.54 billion years old. The geology or deep time of Earth's past has been organized into various units according to events which took place in each period. Different spans of time on the GTS are usually delimited by changes in the composition of strata which correspond to them, indicating major geological or paleontological events, such as mass extinctions. Terminology[edit] History and nomenclature of the time scale[edit] Graphical representation of Earth's history as a spiral

http://en.wikipedia.org/wiki/Geologic_time_scale

Geological history of Earth Geologic time represented in a diagram called a geological clock, showing the relative lengths of the eons of Earth's history and noting major events The geological history of Earth follows the major events in Earth's past based on the geologic time scale, a system of chronological measurement based on the study of the planet's rock layers (stratigraphy). Earth formed about 4.54 billion years ago by accretion from the solar nebula, a disk-shaped mass of dust and gas left over from the formation of the Sun, which also created the rest of the Solar System. As the surface continually reshaped itself over hundreds of millions of years, continents formed and broke apart. They migrated across the surface, occasionally combining to form a supercontinent. Roughly 750 million years ago, the earliest-known supercontinent Rodinia, began to break apart.

Homo habilis Homo habilis (also Australopithecus habilis) is a species of the Hominini tribe, which lived from approximately 2.33 to 1.44 million years ago, during the Gelasian Pleistocene period.[1] While there has been scholarly controversy regarding its placement in the genus Homo rather than the genus Australopithecus,[2][3] its brain size has been shown to range from 550 cm3 to 687 cm3, rather than from 363 cm3 to 600 cm3 as formerly thought.[3][4] These more recent findings concerning brain size favor its traditional placement in the genus Homo, as does the need for the genus to be monophyletic if H. habilis is indeed the common ancestor.[citation needed] Homo habilis has often been thought to be the ancestor of the more gracile and sophisticated Homo ergaster, which in turn gave rise to the more human-appearing species, Homo erectus. Findings[edit]

AMNH, NY: Permanent Exhibitions The Biodiversity and Environmental Halls offer a vivid and inspiring vision of the spectacular beauty and abundance of life on Earth. The Museum’s Birds Halls portray the wide variety of avian life on the planet, and the Hall of Reptiles and Amphibians reviews the anatomy, behavior, and various adaptations of these vertebrates. The Earth and Planetary Sciences halls showcase remarkable specimens, including meteorites, minerals, and rare gems, that offer clues about the origins of our solar system and the dynamic processes of our planet. One of the premier attractions in New York City is the Museum's series of fossil halls, including its two famed dinosaur halls in the David H. Koch Dinosaur Wing, as well as the Lila Acheson Wallace Wing of Mammals and Their Extinct Relatives. The Hall of Human Origins explores the evolutionary story of the human family, while the Cultural Halls examine the cultures of Asia, Africa, North and South America, and the Pacific.

Geological history of Earth Geologic time represented in a diagram called a geological clock, showing the relative lengths of the eons of Earth's history and noting major events The geological history of Earth follows the major events in Earth's past based on the geologic time scale, a system of chronological measurement based on the study of the planet's rock layers (stratigraphy). Earth formed about 4.54 billion years ago by accretion from the solar nebula, a disk-shaped mass of dust and gas left over from the formation of the Sun, which also created the rest of the Solar System. As the surface continually reshaped itself over hundreds of millions of years, continents formed and broke apart.

History of the Earth The history of Earth concerns the development of the planet Earth from its formation to the present day.[1][2] Nearly all branches of natural science have contributed to the understanding of the main events of the Earth's past. The age of Earth is approximately one-third of the age of the universe. An immense amount of geological change has occurred in that timespan, accompanied by biological change. Homo gautengensis Homo gautengensis is a hominin species proposed by biological anthropologist Darren Curnoe in 2010. The species is composed of South African hominin fossils previously attributed to Homo habilis, Homo ergaster or in some cases Australopithecus and is argued by Curnoe to be the earliest species in the genus Homo.[1] Discovery and analysis[edit] Analysis announced in May 2010 of a partial skull found decades earlier in South Africa's Sterkfontein Caves in Gauteng near Johannesburg identified the species, named Homo gautengensis by anthropologist Dr. Darren Curnoe of the UNSW School of Biological, Earth and Environmental Sciences.

History of the Earth The history of the Earth concerns the development of the planet Earth from its formation to the present day.[1][2] Nearly all branches of natural science have contributed to the understanding of the main events of the Earth's past. The age of Earth is approximately one-third of the age of the universe. An immense amount of biological and geological change has occurred in that time span. The first life forms appeared between 3.8 and 3.5 billion years ago. The earliest evidences for life on Earth are graphite found to be biogenic in 3.7 billion-year-old metasedimentary rocks discovered in Western Greenland[3] and microbial mat fossils found in 3.48 billion-year-old sandstone discovered in Western Australia.[4][5] Photosynthetic life appeared around 2 billion years ago, enriching the atmosphere with oxygen.

Seismic Monitor Longitude Latitude New: Earthquake browser with 3D viewer! Nuevo: Navegador de Terremotos con Vista 3D! y Boletines en español IEB is a new, interactive map that not only shows the latest earthquakes but allows you to display thousands of quakes from an archive of 3.4 million spanning from 1970 to minutes ago. Timeline of plant evolution This article attempts to place key plant innovations in a geological context. It concerns itself only with novel adaptations and events that had a major ecological significance, not those that are of solely anthropological interest. The timeline displays a graphical representation of the adaptations; the text attempts to explain the nature and robustness of the evidence. Plant evolution is an aspect of the study of biological evolution, involving predominantly evolution of plants suited to live on land, greening of various land masses by the filling of their niches with land plants, and diversification of groups of land plants. Earliest classifiable plants[edit]

Homo rudolfensis Homo rudolfensis (also Australopithecus rudolfensis) is an extinct species of the Hominini tribe known only through a handful of representative fossils, the first of which was discovered by Bernard Ngeneo, a member of a team led by anthropologist Richard Leakey and zoologist Meave Leakey in 1972, at Koobi Fora on the east side of Lake Rudolf (now Lake Turkana) in Kenya. On 8 August 2012, a team led by Meave Leakey announced the discovery of a face and two jawbones belonging to H. rudolfensis. KNM-ER 1470[edit] UR 501 (original specimen), the oldest fossil of genus Homo The fossil KNM-ER 1470 was the center of much debate concerning its species.

History of the Earth - EvoWiki From EvoWiki Painting of a late Jurassic Scene on one of the large island in the Lower Saxony basin in northern Germany. It shows an adult and a juvenile specimen of the sauropod Europasaurus holgeri and Iguanodons passing by. There are two Compsognathus in the foreground and an Archaeopteryx at the right. According to mainstream science, the universe is approximately 13.7 billion years old. It is thought that our universe's existence can be traced back to an event in space-time known as the Big Bang.

Evolutionary history of plants A late Siluriansporangium. Green: A spore tetrad. Blue: A spore bearing a trilete mark – the -shaped scar. The spores are about 30-35 μm across Hominidae The Hominidae (/hɒˈmɪnɨdiː/; also known as great apes[notes 1]) form a taxonomic family of primates, including four extant genera: The term "hominid" is also used in the more restricted sense as hominins or "humans and relatives of humans closer than chimpanzees".[2] In this usage, all hominid species other than Homo sapiens are extinct. A number of known extinct genera are grouped with humans in the Homininae subfamily, others with orangutans in the Ponginae subfamily. The most recent common ancestor of the Hominidae lived roughly 14 million years ago,[3] when the ancestors of the orangutans speciated from the ancestors of the other three genera.[4] The ancestors of the Hominidae family had already speciated from those of the Hylobatidae family, perhaps 15 million to 20 million years ago.[4][5]

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