Portal:Paleontology

The Palaeontology Portal

Introduction

Paleontology or palaeontology is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geologic time, and assess the interactions between prehistoric organisms and their natural environment. While paleontological observations are known from at least the 6th century BC, the foundation of paleontology as a science dates back to the work of Georges Cuvier in 1796. Cuvier demonstrated evidence for the concept of extinction and how the life of the past was not necessarily the same as that of the present. The field developed rapidly over the course of the following decades, and the French word paléontologie was introduced for the study in 1822, which was derived from the Ancient Greek word for 'ancient' and words describing relatedness and a field of study. Further advances in the field accompanied the work of Charles Darwin who popularized the concept of evolution. Together, evolution and extinction can be understood as complementary processes that shaped the history of life.

Paleontology overlaps the most with the fields of geology and biology. It draws on technology and analysis of a wide range of sciences to apply them to the study of life and environments of the past, particularly for the subdisciplines of paleobiology and paleoecology that are analogous to biology and ecology. Paleontology also contributes to other sciences, being utilized for biostratigraphy to reconstruct the geologic time scale of Earth, or in studies on extinction to establish both external and internal factors that can lead to the disappearance of a species. Much of the history of life is now better understood because of advances in paleontology and the increase in interdisciplinary studies. Several improvements in understanding have occurred from the introduction of theoretical analysis to paleontology in the 1950s and 1960s which led to the rise of more focused fields of paleontology that assess the changing geography and climate of Earth, the phylogenetic relationships between different species, and the analysis of how fossilization occurs and what biases can impact the quality of the fossil record. (Full article...)

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Selected article on the prehistoric world and its legacies

The Cretaceous–Paleogene extinction event, often referred to as the Cretaceous–Tertiary extinction event, was the large-scale mass extinction of animal and plant species in a geologically short period of time, approximately 66 million years ago (mya). The K–Pg extinction event is associated with a geological signature, usually a thin band dated to that time and found in various parts of the world, known as the K–Pg boundary. K is the traditional abbreviation for the Cretaceous Period, and Pg is the abbreviation for the Paleogene Period. The event marks the end of the Mesozoic Era, and the beginning of the Cenozoic Era.

Non-avian dinosaur fossils are only found below the K–Pg boundary and became extinct immediately before or during the event. A very small number of dinosaur fossils have been found above the K-Pg boundary, but they have been explained as reworked, that is, fossils that have been eroded from their original locations then preserved in later sedimentary layers. Mosasaurs, plesiosaurs, pterosaurs and many species of plants and invertebrates also became extinct. Mammalian and bird clades passed through the boundary with few extinctions, and radiation from those Maastrichtian clades occurred well past the boundary. Rates of extinction and radiation varied across different clades of organisms.

Many scientists theorize that the Cretaceous–Paleogene extinctions were caused by one or more catastrophic geological events such as massive asteroid impacts or increased volcanic activity. Several impact craters and massive volcanic activity in the Deccan Traps have been dated to the approximate time of the extinction event. These geological events may have reduced sunlight and hindered photosynthesis, leading to a massive disruption in Earth's ecology. Other researchers believe the extinction was more gradual, resulting from slower changes in sea level or climate. (see more...)

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Did you know?

... that a revolution in burrowing marks the base of the Cambrian period, and is followed by the Cambrian explosion of animal diversity?
... that the extinct Chamaecyparis eureka is the oldest confirmed member of the genus Chamaecyparis?
... that when first described, the extinct bird Cruschedula was thought to be a "dry-land" penguin?
... that Puppigerus, an extinct sea turtle, had a specialized jaw structure which kept it from accidentally inhaling water?
...that Kirill Eskov named a genus from the Linyphiidae spider family discovered by him in 1988 after Kikimora, a female spirit in Slavic mythology?

... that both Fordilla and Pojetaia, Cambrian members of the extinct bivalve family Fordillidae, are part of the Turkish small shelly fauna?
... that, being a descendant of Pliohippus, Astrohippus is not considered to be an ancestor to modern horses?
... that the ichnogenus Chondrites (pictured) can be used as an indicator of anoxia in sediments?
... that the extinct plant species Eucommia jeffersonensis and Eucommia rolandii were both described from fossils in 1997?
... that, when described, the brown lacewing species Wesmaelius mathewesi was the most ancient member of its subfamily?

More did you know facts

General images - load new batch

The following are images from various paleontology-related articles on Wikipedia.

Image 1Illustration from William Smith's Strata by Organized Fossils (1817) (from History of paleontology)
Image 2Fossil of the Taung child discovered in South Africa in 1924 (from History of paleontology)
Image 3Diagram by O.C. Marsh of the evolution of horse feet and teeth, reproduced in T. H. Huxley's 1876 book, Professor Huxley in America (from History of paleontology)
Image 4A Spriggina fossil from the Ediacaran (from History of paleontology)
Image 5Duria Antiquior – A more Ancient Dorset is a watercolor painted in 1830 by the geologist Henry De la Beche based on fossils found by Mary Anning. The late 18th and early 19th century was a time of rapid and dramatic changes in ideas about the history of life on Earth. (from History of paleontology)
Image 6Illustration of the fossil jaw of the Stonesfield mammal from Gideon Mantell's 1848 Wonders of Geology (from History of paleontology)
Image 7Illustration of fossil Iguanodon teeth with a modern iguana jaw for comparison from Mantell's 1825 paper describing Iguanodon (from History of paleontology)
Image 8Geologic time scale from an 1861 book by Richard Owen shows the appearance of major animal types. (from History of paleontology)
Image 9A complete Anomalocaris fossil from the Burgess Shale (from History of paleontology)
Image 10Philippe-Charles Schmerling (from List of paleontologists)
Image 11A drawing comparing jaws was added in 1799 when Cuvier's 1796 presentation on living and fossil elephants was published. (from History of paleontology)
Image 12Illustration from Steno's 1667 paper shows a shark head and its teeth along with a fossil tooth for comparison. (from History of paleontology)
Image 13Photograph of the second Archaeopteryx skeleton to be found, taken in 1881 at the Natural History Museum, Berlin (from History of paleontology)
Image 14Stephan Endlicher (from List of paleontologists)
Image 15Johann Jakob Scheuchzer tried to explain fossils using Biblical floods in his Herbarium of the Deluge (1709). (from History of paleontology)
Image 16First mention of the word palæontologie, as coined in January 1822 by Henri Marie Ducrotay de Blainville in his Journal de physique (from History of paleontology)
Image 17Elmer Riggs and H.W. Menke in Field Columbian Museum's paleontology lab, 1899 (from History of paleontology)

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Selected article on paleontology in human science, culture and economics

Stephen Jay Gould (September 10, 1941 – May 20, 2002) was an American paleontologist, evolutionary biologist, and historian of science. He was also one of the most influential and widely read writers of popular science of his generation. Gould spent most of his career teaching at Harvard University and working at the American Museum of Natural History in New York. In the later years of his life, Gould also taught biology and evolution at New York University.

Gould's most significant contribution to evolutionary biology was the theory of punctuated equilibrium, which he developed with Niles Eldredge in 1972. The theory proposes that most evolution is marked by long periods of evolutionary stability, which is punctuated by rare instances of branching evolution. The theory was contrasted against phyletic gradualism, the popular idea that evolutionary change is marked by a pattern of smooth and continuous change in the fossil record.

Most of Gould's research was based on the land snail genera Poecilozonites and Cerion. He also contributed to evolutionary developmental biology, and has received wide praise for his book Ontogeny and Phylogeny. In evolutionary theory he opposed strict selectionism, sociobiology as applied to humans, and evolutionary psychology. Gould was known by the general public mainly from his 300 popular essays in the magazine Natural History, and his books written for a non-specialist audience. In April 2000, the US Library of Congress named him a "Living Legend". (see more...)

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On this day...

July 28:

1823 - Gaston de Saporta was born in Saint-Zacharie, France.
1840 - Edward Drinker Cope was born in Philadelphia, Pennsylvania, USA.
1893 - Edward Charlesworth died at age 79.
1914 - Joseph T. Gregory was born in Eureka, California, USA.
1937 - Frederic Brewster Loomis died of a brain hemorrhage in Sitka, Alaska, USA.

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Selected image

A 95-million-year-old slab of fossiliferous rock from Hakel, Lebanon measuring 24 cm in width. The specimen prominently preserves a member of the lobster genus Pseudostacus as well as the fish Diplomystus birdii A fragmentary specimen of an additional fish, Dercetis triqueter, is visible in the lower right-hand corner of the specimen.
Photo credit: Brocken Inaglory