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            Dinosaurs

            Dinosaurs are a prehistoric species that lived on Earth from 230 to 65 million years ago.

            Asked in Dinosaurs, Extinct Animals

            What do scientists believe caused the extinction of the dinosaurs?

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            Scientists have many theories about what caused the extinction of dinosaurs. Below are thoughts on some of the most common theories: Since about 90% of dinosaurs were herbivores (plant eaters), it was thought that when an asteroid hit earth and many tons of dust was thrown into the atmosphere that the result was a "long night" due to the lack of sunlight that was able to reach earth, the plants died out and without a food source, so did the dinosaurs. It could also have been the combination of the Chicxulub asteroid impact event (causing worldwide fires and environmental catastrophe) in association with the Deccan Traps volcanic event, which occurred at around the same time, or possibly as a result of, the asteroid impact event. There are many theories that are written throughout history of why the dinosaurs exactly were driven into extinction. Most are meteor impact related. By looking at craters all over the world, scientists can estimate the meteors size, speed and its impacts effect on the local environment. See the related link for more information. Though the large meteorite impact (Chicxulub) figures prominently in a lot of the theories of how the dinosaurs became extinct, the idea of a gamma ray burst has also come up now that we are aware of them and the threat they pose. Additionally, there was an "outburst" of volcanic activity during this period. This extinction event is at the Cretaceous-Tertiary (K-T) boundary. It should also be added that several other large impact events occurred right about the time of Chicxulub, including Silverpit and Boltysh craters, among others. It seems the deck was "stacked against" the dinosaurs, regardless of how you look at it. It is possible that things are "found" to "corroborate" extinction by space rock, but the facts are pretty convincing, even for the skeptic. It was noted but is worth repeating: many of the ideas that represent credible ways that could have triggered the dinosaurs' extinction could have arisen separately and acted in concert to kill off all these creatures. One thing is certain - they're gone. And the demise of the terrible lizards was caused by something dramatic given the relatively narrow window in which they disappeared. The hypothesis that states an asteroid-impact was the sole cause of the extinction is just that - an hypothesis, not a fact. Most paleontologists feel that the asteroid impact was just one of a series of catastrophic events that ultimately wiped out the dinosaurs. There is evidence of a huge meteor strike just off the Yucatan Peninsula, true. And a meteor may well have put a final period to the extinction pulse. But there is also evidence that other factors may have been involved. For one thing, the dinosaurs didn't become extinct all at once. The pulse seems to have taken more than 10-thousand years to complete which makes the asteroid theory implausible as a complete explanation. There is evidence that there was massive volcanic activity also, and a drastic climatic change. The dinosaurs were in decline in number of species long before the K/T extinction was over. Furthermore, some dinosaurs did survive into Laramide time - the birds are still around (admittedly that's begging the issue, but it's not unreasonable to ask how they managed to survive when so many their brethren were killed). Dinosaurs were already fast becoming endangered species before the Chicxulub impact. Increased volcanic activity such as the Deccan Traps in modern day India was slowly killing many species. Between 68 to 60 million years ago 150,000 km2 of igneous rock was deposited in places more than 2 km thick. The bulk of the eruptions occurred about 66 million years ago near modern day Mumbai. These eruptions lasted as little as 33,000 years but the effect on the environment would have been staggering. Dust and debris thrown into the atmosphere along with sulphur dioxide would have cooled the earth. Also many poisonous gases would also have been released. Studies on modern day birds suggest that these poisonous gases not only directly killed dinosaurs but also caused thinning of the shells of their eggs which meant that many would fail to hatch. It has also been suggested that disease killed off the dinosaurs. A very deadly and contagious disease may have circulated among the dinosaurs forcing them to become extinct. Still yet another theory is that the Earth just gradually changed in climate over a long time period and the dinosaurs were not able to adapt to the cooler, dryer climate. When the continents broke up, they couldn't get to new feeding grounds when theirs were exhausted ------------------------------------------- It mst also be pointed out that the avian type dinosaurs (the birds), did not become extinct and are living today.
            Asked in Paleontology, Dinosaurs, Asteroids

            What caused the extinction of the dinosaurs?

            User Avatar
            Scientists have many theories about what caused the extinction of dinosaurs. Below are thoughts on some of the most common theories: Since about 90% of dinosaurs were herbivores (plant eaters), it was thought that when an asteroid hit earth and many tons of dust was thrown into the atmosphere that the result was a "long night" due to the lack of sunlight that was able to reach earth, the plants died out and without a food source, so did the dinosaurs. It could also have been the combination of the Chicxulub asteroid impact event (causing worldwide fires and environmental catastrophe in association with the Deccan Traps volcanic event, which occurred at around the same time, or possibly as a result of, the asteroid impact event. There are many theories that are written throughout history of why the dinosaurs exactly were driven into extinction. Most are meteor impact related. By looking at craters all over the world, scientists can estimate the meteors size, speed and its impacts effect on the local environment. See the related link for more information. Though the large meteorite impact (Chicxulub) figures prominently in a lot of the theories of how the dinosaurs became extinct, the idea of a gamma ray burst has also come up now that we are aware of them and the threat they pose. Additionally, there was an "outburst" of volcanic activity during this period. This extinction event is at the Cretaceous-Tertiary (K-T) boundary. It should also be added that several other large impact events occurred right about the time of Chicxulub, including Silverpit and Boltysh craters, among others. It seems the deck was "stacked against" the dinosaurs, regardless of how you look at it. It is possible that things are "found" to "corroborate" extinction by space rock, but the facts are pretty convincing, even for the skeptic. It was noted but is worth repeating: many of the ideas that represent credible ways that could have triggered the dinosaurs' extinction could have arisen separately and acted in concert to kill off all these creatures. One thing is certain - they're gone. And the demise of the terrible lizards was caused by something dramatic given the relatively narrow window in which they disappeared. The hypothesis that states an asteroid-impact was the sole cause of the extinction is just that - an hypothesis, not a fact. Most paleontologists feel that the asteroid impact was just one of a series of catastrophic events that ultimately wiped out the dinosaurs. There is evidence of a huge meteor strike just off the Yucatan Peninsula, true. And a meteor may well have put a final period to the extinction pulse. But there is also evidence that other factors may have been involved. For one thing, the dinosaurs didn't become extinct all at once. The pulse seems to have taken more than 10-thousand years to complete which makes the asteroid theory implausible as a complete explanation. There is evidence that there was massive volcanic activity also, and a drastic climatic change. The dinosaurs were in decline in number of species long before the K/T extinction was over. Furthermore, some dinosaurs did survive into Laramide time - the birds are still around (admittedly that's begging the issue, but it's not unreasonable to ask how they managed to survive when so many their brethren were killed). Dinosaurs were already fast becoming endangered species before the Chicxulub impact. Increased volcanic activity such as the Deccan Traps in modern day India was slowly killing many species. Between 68 to 60 million years ago 150,000 km2 of igneous rock was deposited in places more than 2 km thick. The bulk of the eruptions occurred about 66 million years ago near modern day Mumbai. These eruptions lasted as little as 33,000 years but the effect on the environment would have been staggering. Dust and debris thrown into the atmosphere along with sulphur dioxide would have cooled the earth. Also many poisonous gases would also have been released. Studies on modern day birds suggest that these poisonous gases not only directly killed dinosaurs but also caused thinning of the shells of their eggs which meant that many would fail to hatch. It has also been suggested that disease killed off the dinosaurs. A very deadly and contagious disease may have circulated among the dinosaurs forcing them to become extinct. Still yet another theory is that the Earth just gradually changed in climate over a long time period and the dinosaurs were not able to adapt to the cooler, dryer climate.
            Asked in Dinosaurs, Scattergories and Words Starting with Certain Letters, Adjectives and Articles

            What are some adjectives that begin with the letter F?

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            Some adjectives that begin with the letter F are: fabled fabulous factual fad faded failed failing (as in a failing grade) faint fair, fairer, fairest faithful faithless fake fallacious fallow false faltering familiar famished famous fanatical fanciful fancy, fancier, fanciest fantabulous fantastic fantastical far, farther, farthest far-fetched far-off fascinated fascinating fashionable fast, faster, fastest fastidious fasting fat, fatter, fattest fatal fated fatherly fatigued fatty faulty favorable favorite feared fearful fearing fearless fearsome feathered feathery feeble feigned feisty, feistier, feistiest feline felonious female feminine feral ferocious fertile fervent festering festive festooned few fey fibrous fickle fictional fictitious fidgety fierce, fiercer, fiercest fiery fifth fifty Filipino filled filling filthy, filthier, filthiest final financial fine, finer, finest finicky finished finite Finnish fireproof firm, firmer, firmest first firsthand fishy, fishier, fishiest fit, fitter, fittest fitful fitted fitting five fixated fixed fizzy, fizzier, fizziest flabby, flabbier, flabbiest flagrant flaky, flakier, flakiest flamboyant flammable flared flashy, flashier, flashiest flat, flatter, flattest flattering flatulent flawed flawless flecked fleecy fleshy flexible flighty, flightier, flightiest flimsy flippant flirtatious flirty flitting floated flocked floppy, floppier, floppiest floury flowery fluctuating fluent fluffy fluid fluky fluorescent flustered fluted fluttering flying foamy, foamier, foamiest focused (as in He's a very focused individual) foggy folksy foolhardy foolish forceful foregoing foreign forgetful forked formal formative former formidable forsaken forthright fortuitous fortunate forward foul, fouler, foulest fouled found four fourth foxy fractured fragile fragmented fragrant frail frank frankly frantic fraudulent freaked-out freaky, freakier, freakiest free freed freezing French frenetic frequent fresh fretful friendly, friendlier, friendliest frightened frightening frightful frigid frilly frisky frivolous frizzy, frizzier, frizziest frontal frosted frosty, frostier, frostiest frothy frozen frugal fruitful fruity frumpy frustrating fudgy full full-figured fumbling fun functional fundamental funky funny, funnier, funniest furrowed furry, furrier, furriest furtive fussy, fussier, fussiest futile future futuristic fuzzy, fuzzier, fuzziest · faithful · fanatical · fearless · feisty · fickle · finicky · flaky · flawless · forgetful · funny
            Asked in Prehistoric Animals, Dinosaurs

            What are leaf eating dinosaurs called?

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            Plant eating dinosaurs are referred to the same way plant eating animals are classified today. The word you're looking for is herbivores
            Asked in History, Politics & Society, Dinosaurs

            What is dinosaur mentality?

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            How smart were they? The general answer is that every successful animal is just as smart as it needs to be. While that isn't very helpful if you're looking for an IQ score, it's significant for understanding. Big herbivores don't need particularly big brains because their need for intelligence is low: the eat, they mate, they flee from danger. The brain of a predator does need to be good and the brain of a small animal with many different predators trying to eat it hardly less good. Tyrannosaurs had bigger brains than humans, but of course they were bigger creatures. Also, much of their brains were probably (we're guessing based on shape) devoted to sense of smell. Some man-sized dinosaurs like saurorthoides had brains as big as ostriches'.
            Asked in Dinosaurs, Fossils

            Why were there never dinosaurs found in Louisiana?

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            The eastern United States is primarily composed of marine deposits from the Paleozoic, meaning that most fossils are of fish, mollusks, and arthropods. Dinosaurs have only been found in four states east of the Great Plains: Alabama, Maryland, Missouri, and New Jersey.
            Asked by Archibald Bernier in Dinosaurs, Paleontology

            Do we know what dinosaurs sounded like?

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            In a word, no, but scientists can make educated guesses. The closest living relatives of the dinosaurs are crocodilians and birds, and we can look to the ways they vocalize to give us a hint. Alligators and crocodiles use their larynxes to communicate—they’ll hiss, groan, and yes, roar (here’s a compilation of their sounds). Dinosaurs might have had larynxes, but since those don’t fossilize, it’s impossible to know for sure. Birds, meanwhile, use an organ called a syrinx, which seems to have evolved after dinosaurs. That might indicate that dinos couldn’t vocalize at all, which would be a bummer. However, there’s also a possibility that they evolved a unique way to vocalize. For example, based on studying their skulls and inner ears, some have theorized that hadrosaurs used their crests to bellow at each other. So, they probably didn’t roar, but bellowing can be pretty cool too, right?
            Asked in Dinosaurs, History of Science, Fossils

            Where was the first fossil in Alberta found?

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            It was found near the Badlands in Drumheller.
            Asked in Dinosaurs

            How long ago did the ichthyosaurus live?

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            The Ichthyosaurs, predatory sea reptiles, were rather like modern dolphins. They existed from the Early Triassic Period (250 million years ago) till the Middle Cretaceous Period (100 million years ago).
            Asked in India, Dinosaurs

            Did Dinosaurs live in India?

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            Yes, many species of dinosaur lived in India in the Mesozoic era. Rajasaurus and Isisaurus are some named examples, interestingly with Rajasaurus sharing the name of an Indian prince. See the related link below.
            Asked in Dinosaurs

            What noise does a dinosaur make?

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            Most dinosaurs made a roar, bellow, or whine kind of noise.
            Asked in Dinosaurs

            Was there a dinosaur without a tail?

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            No, there is no evidence of terrestrial dinosaurs which lacked a pronounced tail. But modern penguins would probably qualify for not having a tail.
            Asked in Dinosaurs, Biggest, Strongest, Fastest and Other Extremes

            Which was the strongest dinosaur in the world?

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            Answer 1 if you mean strongest, then probably one of the sauropods, such as seismosaurus or amphicoelias if it existed. However, they aren't neccessarily the most effective at battle, since t-rex was tall enough to reach their neck and simply crush it (which in turn would be smashed to bits by Ankylosaurus which in turn would be crushed by the large sauropods...) Answer 2 Amphicoelias probably it could just crush everything in its way.
            Asked in Dinosaurs

            Do dinosaurs go to heaven?

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            It depends on what one believes, mostly.
            Asked in Reptiles, Dinosaurs

            What are some of the features that dinosaurs share with modern reptiles?

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            Both reptiles and dinosaurs lay eggs and many reptiles have similar skin to what we believe dinosaurs had. Also, alligators and crocodiles are very similar to predator dinosaurs, e.g T-Rex, Spinosaurus etc., as they have many sharp teeth and also their skin is very similar. Another similarity could be that, many lizards have a "line" that raises from their skin running through their back and if you look at some dinosaurs, such as the Spinosaurus and many others, you can see they share the same feature only that it is much larger.
            Asked in Dinosaurs

            Did humans live before dinosaurs?

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            No! Current scientific studies show that humans did not exist until 65 million years AFTER the dinosaurs became extinct! If we did exist before and when the dinosaurs existed, the dinosaurs would have killed us all off!
            Asked in Dinosaurs, Prehistoric Animals

            Did some dinosaurs evolve into sentient beings?

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            The most widely accepted definition of sentience is possessing the cognitive ability to think for oneself autonomously and experience subjectivity. However, for others, the innate ability to experience pleasure and pain defines sentience. However, this is a very loose definition, given that pleasure and pain are merely one axis of information-encoding phenomena. Therefore, cognitive autonomy and subjectivity is more accurate. When most people speak of "dinosaurs", they are usually speaking of the birds and lizards that existed prior to the tertiary period. In such a case, we can say that dinosaurs are not sentient. The reptilian brain is not capable of the level of cognitive ability that we common define as "sentient". Yet, if you are very loosely using the term "dinosaur" to mean anything from before the tertiary period forward, then you can say that, yes, the smaller lifeforms that evolved along the same lines as the hominids (smaller animals that would have been prey to the larger, carnivorous lizards long ago) did end up becoming humans.
            Asked in Dinosaurs

            When did the dinosaurs appear on earth?

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            230 million years ago.
            Asked in Prehistoric Animals, Dinosaurs, Extinct Animals

            What was the first dinosaur with feathers?

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            This is a tricky question for many scientists for two reasons. The first being that feathers cannot be fossilized with the bone. We have to look for their imprints in the surrounding rock, and even those are rare. The second is that the line between dinosaur and bird is very thin. If you mean all dinosaurs including birds, then primitive fliers such as Archaeopteryx had the first feathers. If not, then a Early Cretaceous genus called Sinosauropteryx is the first known non-avian (not a bird, per se) dinosaur to have feathers.
            Asked in Greece, Dinosaurs

            Were there any Dinosaurs in Greece?

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            During the times of the dinosaurs, Greece did not exist. The lands looked extremely different to how they do today. Dinosaurs dominated every single continent on the globe, so, yes, dinosaurs did live in what is nowadays recognised as Greece.
            Asked in Prehistoric Animals, Dinosaurs

            What animal has been around since pre-historic times?

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            Most animals, (including humans), evolved in prehistoric times. It is far harder to name an animal that has evolved after prehistoric times. EDIT Some good examples of blueprints of animals that have existed for millions of years are sharks and another species of fish I can name is the Coelacanth that is still around today :).
            Asked in Dinosaurs

            Do dinosaurs kill each other?

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            well of course they do!!!!!!
            Asked in Dinosaurs

            Did eoraptor have any enemies?

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            Eoraptor lived in a perilous environment, fraught with danger. The largest predator around was Saurosuchus, a 20 foot crocodile relative. Saurosuchus could easily swallow a Eoraptor whole! Eoraptor also had to contend with Herrerasaurus, another early carnivorous dinosaur.

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