What is "extinction"

Extinction \Ex*tinc"tion\, n. [L. extinctio, exstinction: cf. F. extinction.]

1. The act of extinguishing or making extinct; a putting an end to; the act of putting out or destroying light, fire, life, activity, influence, etc.

2. State of being extinguished or of ceasing to be; destruction; suppression; as, the extinction of life, of a family, of a quarrel, of claim.

3. Specifically: The ceasing to exist of a species of living organism, such as a plant or animal, whose numbers declined to the point where the last member of the species died and therefore no new members of the species could ever again be born.

   Note: Extinctions have occurred many times throughout the history of life on Earth, and abundant evidence of the prior existence of animals and plants are found as fossils in rock formations many millions of years old. It is believed by some that due to the influence of man on the environment and destruction of habitat, the rate of extinction of species is now higher than at any previous time on this planet. Extinctions of some animals in recent years have actually been reliably recorded, such as that of the dodo bird. A remarkable example of extinction is that of the passenger pigeon ( Ectopistes migratorius) in North America, which once numbered in the billions, and the last living member of which species was recorded as dying in captivity in 191

early 15c., "annihilation," from Latin extinctionem/exstinctionem (nominative extinctio/exstinctio) "extinction, annihilation," noun of action from past participle stem of extinguere/exstinguere "quench, wipe out" (see extinguish). Originally of fires, lights; figurative use, the wiping out of a material thing (a debt, a person, a family, etc.) from early 17c.; of species by 1784.

n. The action of making or becoming extinct; annihilation.

1. n. no longer in existence; "the extinction of a species" [syn: defunctness]

2. no longer active; extinguished; "the extinction of the volcano"

3. the reduction of the intensity of radiation as a consequence of absorption and radiation

4. complete annihilation; "they think a meteor cause the extinction of the dinosaurs" [syn: extermination]

5. a conditioning process in which the reinforcer is removed and a conditioned response becomes independent of the conditioned stimulus [syn: experimental extinction]

6. the act of extinguishing; causing to stop burning; "the extinction of the lights" [syn: extinguishing, quenching]

In biology and ecology, extinction is the end of an organism or of a group of organisms ( taxon), normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence.

More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's current species range from 10 million to 14 million, of which about 1.2 million have been documented and over 86 percent have not yet been described.

Through evolution, species arise through the process of speciation—where new varieties of organisms arise and thrive when they are able to find and exploit an ecological niche—and species become extinct when they are no longer able to survive in changing conditions or against superior competition. The relationship between animals and their ecological niches has been firmly established. A typical species becomes extinct within 10 million years of its first appearance, although some species, called living fossils, survive with virtually no morphological change for hundreds of millions of years.

Mass extinctions are relatively rare events; however, isolated extinctions are quite common. Only recently have extinctions been recorded and scientists have become alarmed at the current high rate of extinctions. Most species that become extinct are never scientifically documented. Some scientists estimate that up to half of presently existing plant and animal species may become extinct by 2100.

Extinction is in biology and palaeontology, the end of a species or other taxon. Extinction may also refer to:

• Extinction (peerage), in the United Kingdom, happens when all possible heirs of a peer have died out

"Extinction" is the fifty-fifth episode of the American science fiction television series Star Trek: Enterprise, the third episode of season three. It first aired on September 24, 2003, on the UPN network in the United States. This was the first episode following the addition of the prefix "Star Trek" to the title of the series. Set in the 22nd century, the series follows the adventures of the first Starfleet starship, Enterprise, registration NX-01.

Season three of Enterprise features an ongoing story following an attack on Earth by previously unknown aliens called the Xindi. In this episode, while investigating a planet visited by the Xindi, several crewmembers including Captain Jonathan Archer become infected with a virus that mutates them into another species. The crew of the Enterprise must prevent an alien race from exterminating the mutated crew-members while developing a cure themselves. The episode was written by story editor André Bormanis and directed by Star Trek: The Next Generation alumnus LeVar Burton.

"Extinction" was shot across seven days, with the soundstage transformed into an alien jungle for filming. John Eaves designed a Xindi pod, as well as an alien spaceship which he strongly disliked. Jolene Blalock, Scott Bakula, Linda Park and Dominic Keating were each required to undergo extended make-up sessions during six days of the shoot in order to show their characters in various states of mutation. Around four million viewers watched "Extinction" on first broadcast, but the critical reception was mixed. Although the actors who underwent additional make-up were praised, the plot was found to be similar to previous episodes in the franchise and the ending was poor.

Extinction is a fantasy novel by Lisa Smedman. It is the fourth book of the Forgotten Realms series, War of the Spider Queen hexalogy. Like other books in the series, it is based on the Dungeons & Dragons fantasy role-playing game.

Extinction is the last of Thomas Bernhard’s novels. It was originally published in German in 1986.

Extinction is a neurological disorder that impairs the ability to perceive multiple stimuli of the same type simultaneously. Extinction is usually caused by damage resulting in lesions on one side of the brain. Those who are affected by extinction have a lack of awareness in the contralesional side of space (towards the left side space following a right lesion) and a loss of exploratory search and other actions normally directed toward that side.

In astronomy, extinction is the absorption and scattering of electromagnetic radiation by dust and gas between an emitting astronomical object and the observer. Interstellar extinction was first documented as such in 1930 by Robert Julius Trumpler. However, its effects had been noted in 1847 by Friedrich Georg Wilhelm von Struve, and its effect on the colors of stars had been observed by a number of individuals who did not connect it with the general presence of galactic dust. For stars that lie near the plane of the Milky Way and are within a few thousand parsecs of the Earth, extinction in the visual band of frequencies ( Photometric system) is on the order of 1.8 magnitudes per kiloparsec.

For Earth-bound observers, extinction arises both from the interstellar medium (ISM) and the Earth's atmosphere; it may also arise from circumstellar dust around an observed object. The strong atmospheric extinction in some wavelength regions (such as X-ray, ultraviolet, and infrared) requires the use of space-based observatories. Since blue light is much more strongly attenuated than red light, extinction causes objects to appear redder than expected, a phenomenon referred to as interstellar reddening.

Extinction is observed in both operantly conditioned and classically conditioned behavior. When operant behavior that has been previously reinforced no longer produces reinforcing consequences the behavior gradually stops occurring. In classical conditioning, when a conditioned stimulus is presented alone, so that it no longer predicts the coming of the unconditioned stimulus, conditioned responding gradually stops. For example, after Pavlov's dog was conditioned to salivate at the sound of a bell, it eventually stopped salivating to the bell after the bell had been sounded repeatedly but no food came. Many anxiety disorders such as posttraumatic stress disorder are believed to reflect, at least in part, a failure to extinguish conditioned fear.

Extinction is a term used in optical mineralogy and petrology, which describes when cross-polarized light dims, as viewed through a thin section of a mineral in a petrographic microscope. Isotropic minerals, opaque (metallic) minerals, or amorphous materials (glass) show no light (i.e. constant extinction). Anisotropic minerals will show one extinction for each 90 degrees of stage rotation.

The extinction angle is the measure between the cleavage direction or habit of a mineral and the extinction. To find this, simply line up the cleavage lines/long direction with one of the crosshairs in the microscope, and turn the mineral until the extinction occurs. The number of degrees the stage was rotated is the extinction angle, between 0-89 degrees. 90 degrees would be considered zero degrees, and is known as parallel extinction. Inclined extinction is a measured angle between 1-89 degrees. Minerals with two cleavages can have two extinction angles, with symmetrical extinction occurring when minerals have multiple angles that are the same. Minerals that have no cleavage or elongation can not have an extinction angle.

Minerals with undulose extinction, solid solution/zonation, or other factors (e.g. bird's eye extinction in mica) that may inhibit this measure and may be more difficult to use.

Extinction (formerly known as Welcome to Harmony) is a 2015 post-apocalypse horror film directed by Miguel Ángel Vivas who also co-wrote the screenplay with Alberto Marini from the novel "Y pese a todo" by Juan de Dios Garduno. The stars of "Extinction" are Matthew Fox, Jeffrey Donovan and Quinn McColgan. In a post-apocalypse future, three survivors confront issues from their past, as well as a race of crazed zombies. The film was released on July 31, 2015 in the United States.

Extinction is the first studio album by New York City crust punk band Nausea. It was released in 1990 on Profane Existence.