Also known as the K – T extinction event, it is associated with a geological signature known variously as the K – T boundary, the Cretaceous – Paleogene boundary or the K – Pg boundary, usually a thin band of sedimentation visible wherever rocks of this age are exposed.

None of them are known to survive into the Paleogene, and their persistence into the latest Maastrichtian therefore provides strong evidence for a mass extinction of archaic birds coinciding with the Chicxulub asteroid impact.

The Cenozoic is also known as the Age of Mammals, because the extinction of many groups allowed mammals to greatly diversify.

and on a natural global scale is known to cause the extinction of many species.

Because of its magnitude, scientists formerly speculated that the gases released during the formation of the Deccan Traps played a role in the Cretaceous – Paleogene extinction event ( also known as the K-Pg extinction ), which included the extinction of the non-avian dinosaurs.

An extinction event ( also known as: mass extinction, extinction-level event ( ELE ), or biotic crisis ) is a widespread and rapid decrease in the amount of life on earth.

The Holocene extinction includes the disappearance of large mammals known as megafauna, starting between 9, 000 and 13, 000 years ago, the end of the last Ice Age.

For example, the only pinniped ever known to the Caribbean, the Caribbean monk seal once occurred in Jamaican waters and has now been driven to total extinction.

The era began in the wake of the Permian-Triassic event, the largest mass extinction in Earth's history, and ended with the Cretaceous – Paleogene extinction event, another mass extinction which is known for having killed off non-avian dinosaurs, as well as other plant and animal species.

It is also known as the " Great Dying " because it is considered the largest mass extinction in the Earth's history.

It is also the only known mass extinction of insects.

The Permian – Triassic ( P – Tr ) extinction event, informally known as the Great Dying, was an extinction event that occurred 252. 28 Ma ( million years ) ago, forming the boundary between the Permian and Triassic geologic periods, as well as the Paleozoic and Mesozoic eras.

It is the Earth's most severe known extinction event, with up to 96 % of all marine species and 70 % of terrestrial vertebrate species becoming extinct.

It is the only known mass extinction of insects.

This phenomenon, known as ecological naivete, has resulted in numerous declines in many species and has been strongly implicated in the extinction of the Guadalupe Storm Petrel.

If a predator hunts its prey species to numbers too low to sustain the population in the short term, they can cause not only the extinction or extirpation of the prey, but also the extinction of their own species, a phenomenon known as coextinction.

Impulses originating from or below the His bundle, also known as ventricular, will produce a wide QRS complex with heart rates between 20 and 40 bpm.

Enhanced Data rates for GSM Evolution ( EDGE ) ( also known as Enhanced GPRS ( EGPRS ), or IMT Single Carrier ( IMT-SC ), or Enhanced Data rates for Global Evolution ) is a digital mobile phone technology that allows improved data transmission rates as a backward-compatible extension of GSM.

These specific studies have shown that episodic memory performance does in fact decline with age and have made known that older adults produce vivid rates of forgetting when two items are combined and not encoded.

Singer trained as an atmospheric physicist and is known for his work in space research, atmospheric pollution, rocket and satellite technology, his questioning of the link between UV-B and melanoma rates, and that between CFCs and stratospheric ozone loss

In many countries the ISO codes for the more common currencies are so well known publicly that exchange rates published in newspapers or posted in banks use only these to delineate the different currencies, instead of translated currency names or ambiguous currency symbols.

Excessive debt is known to ultimately have negative consequences for the economy, although monetary policy, such as low interest rates, is used to increase borrowing and stimulate growth.

Minimum wage rates vary greatly across many different jurisdictions, not only in setting a particular amount of money ( e. g. US $ 7. 25 per hour under U. S. Federal law ( or 2. 13 for employees who receive tips, known as the tipped minimum wage ), $ 9. 04 in the U. S. state of Washington, and £ 6. 08 ( for those aged 21 +) in the United Kingdom ), but also in terms of which pay period ( e. g. Russia and China set monthly minimums ) or the scope of coverage.

In the United States, earned income tax credit rates, also known as EITC or EIC, vary by state — some are refundable while other states do not allow a refundable tax credit.

Although invertebrate species remain poorly studied on Madagascar relative to other wildlife, researchers have found high rates of endemism among the known species.

Radiometric dating ( often called radioactive dating ) is a technique used to date materials such as rocks, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates.

The contention of the proponents, that the tax rate cuts would more than pay for themselves, was influenced by a theoretical taxation model based on the elasticity of tax rates, known as the Laffer curve.

For generalized or extended thermodynamics, the definition of the quantity known as the entropy of a small local region is in terms beyond those of classical thermodynamics ; in particular, flow rates are admitted into the definition of the entropy of a small local region.

There also remained a strong economic divide between the north and south of England during this period, with the south of England and the Midlands fairly prosperous by the Thirties, while parts of south Wales and the industrial north of England became known as " distressed areas " due to particularly high rates of unemployment and poverty.

Nevertheless, the Hubble sequence is still commonly used in the field of extragalactic astronomy and Hubble types are known to correlate with many physically relevant properties of galaxies, such as luminosities, colours, masses ( of stars and gas ) and star formation rates.

An NPV calculated using variable discount rates ( if they are known for the duration of the investment ) better reflects the situation than one calculated from a constant discount rate for the entire investment duration.

Because Medicare offers statutorily determined benefits, its coverage policies and payment rates are publicly known, and all enrollees are entitled to the same coverage.

Increased rates of depression are known to produce higher rates of obesity through decreased physical activity.

The conversion rates between various common taels were well known.

In the early 20th century, radioactive materials were known to have characteristic exponential decay rates or half lives.

Graham's Law can also be used to find the approximate molecular weight of a gas if one gas is a known species, and if there is a specific ratio between the rates of two gases ( such as in the previous example ).

Even the knowledge that she was losing another boy, as a mother always does when a marriage is made, did not prevent her from having the first carefree, dreamless sleep that she had known since they dropped down the canyon and into Bear Valley, way, way back there when they were crossing those other mountains.

Those writers known collectively as the `` Southern school '' have received accolades from even those critics least prone to eulogize ; ;

Besides, Miss Henrietta -- as she was generally known since she had put up her hair with a chignon in the back -- had little time to spare them from her teaching and writing ; ;

The malady was popularly known as the `` Spanish flu '' from the alleged locale of its origin.

In light of the scholarly reappraisals engendered by the higher criticism this is a most remarkable statement, particularly coming from one who was well known for his antifundamentalist views.

This is a phenomenon familiar to all radio listeners, resulting from reflection of skywave signals at night from the ionized layer in the upper atmosphere known as the ionosphere.

The turret screw machine, now known as the Brown & Sharpe hand screw machine, takes its ancestry directly from Mr. Brown's efforts to introduce equipment to simplify the manufacture of the sewing machine.

At the beginning of the Hippodrome I saw the Kaiser's Fountain, an ugly octagonal building with a glass dome, built in 1895 by the German Emperor, and on my left, directly across from it, the tomb of Sultan Ahmet, who constructed the Blue Mosque, more properly known by his name.

Until better records have been kept over longer periods of time and much more is known about the maximum dimensions, it will be wise to refrain from drawing conclusions.

It was assumed that the shift in autonomic hypothalamic balance occurring spontaneously in neuropsychiatric patients from the application of certain therapeutic procedures follows the pattern known from the sleep-wakefulness cycle.

In this case the stage R operating with conditions Af transforms the state of the stream from Af to Af, but only the probability distribution of Af is known.

Consultation with a reputable wine dealer and constant experimentation -- `` steering ever from the known to the unknown '' -- are the requisites.

It is known that Morse did associate with a group of itinerant horse traders who made their headquarters at Westport, a town not far from Fall River.

He sucked in his breath and kept quiet while Killpath laid down the sheet again, wound the gold-wire stems of his glasses around his ears and then, eying the report as it lay before him on the desk, intoned, `` Acting Lieutenant Gunnar Matson one failed to see that the station keeper was properly relieved two absented himself throughout the entire watch without checking on the station's activities or the whereabouts of his section sergeants three permitted members of the Homicide Detail of the Inspector's Bureau to arrogate for their own convenience a patrolman who was thereby prevented from carrying on his proper assignment four failed to notify the station commander Acting Captain O. T. Killpath of a homicide occurring in the district five frequented extralegal establishments known as after-hours spots for purposes of an unofficial and purportedly social nature and six '' -- he leaned back and peeled off his glasses `` -- failed to co-operate with the Acting Captain by returning promptly when so ordered.

Thus, while it remains possible that the Babylonians and/or the Pythagoreans may perhaps have had the magic square of three before the Chinese did, more definite evidence will have to turn up from the Middle East or the Classical World before China can lose her claim to the earliest known magic square by more than a thousand years.

What was omitted from `` A Neglected Education '' were those essentials known as `` the facts of life ''.

Perhaps he had known then where that hundred dollar bill had come from and where it was taking his wife.

Alchemy is an influential philosophical tradition whose early practitioners ' claims to profound powers were known from antiquity.

As sun-god and god of light, Apollo was also known by the epithets Aegletes ( ; Αἰγλήτης, Aiglētēs, from αἴγλη, " light of the sun "), Helius ( ; Ἥλιος, Helios, literally " sun "), Phanaeus ( ; Φαναῖος, Phanaios, literally " giving or bringing light "), and Lyceus ( ; Λύκειος, Lukeios, from Proto-Greek * λύκη, " light ").

For this he was also known as Parnopius ( ; Παρνόπιος, Parnopios, from πάρνοψ, " locust ") and to the Romans as Culicarius ( ; from Latin culicārius, " of midges ").

To the Romans, he was known in this capacity as Averruncus ( ; from Latin āverruncare, " to avert ").