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

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It mst also be pointed out that the avian type dinosaurs (the birds), did not become extinct and are living today.
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What caused the extinction of the dinosaurs?

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 km 2 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.

Did tsunamis cause the dinosaur extinction?

No. Scientists believe that a giant meteor hit the Earth, killing all the dinosaurs and causing their extinction. It is true that the extinction of dinosaurs is mostly due to the meteor that hit earth during the time but according to scientists, only around 60 percent of the organisms on earth died due to direct impact. Some other reasons the dinosaurs are extinct may have included climate change, competition, or volcanic eruptions. And on the part about tsunamis, there actually was a massive tsunami near the Gulf of Mexico after the disturbance of the meteor that swept nearly 180 miles inland. But it was the meteor that caused the tsunami and also then the meteor, not the tsunami that may have contributed to the extinction of dinosaurs. .

Why do scientists believe dinosaurs became extinct?

because back in the 1800's there was this huge asteroid that hit the earth. since it was so big all the dinosaurs in the world all died and now u can find dinosaur tracks on the ocean floor, rivers, lakes, and other bodies of water.so they died and became extinct because of the asteroid. that's how it happened because back in the 1800's there was this huge asteroid that hit the earth. since it was so big all the dinosaurs in the world all died and now u can find dinosaur tracks on the ocean floor, rivers, lakes, and other bodies of water.so they died and became extinct because of the asteroid. that's how it happened

When were Dinosaurs believed to have becomed extinct?

Dinosaurs became extinct along with many other types of ancient organisms in the K-T mass extinction that occurred 65 million years ago which probably coincided with an asteroid impact. This marked the end of the Mesozoic Era and the beginning of the Cenozoic.

What do scientist believes how the universe was caused?

answ2 No one knows other than our present grasp of physics is insufficient to answer the Question. It is tempting to say that the Big Bang was preceded by a sense of anticipation - but that is tautology. But it is good fun trying to find the right questions.

How do scientists know the dinosaurs are extinct?

Since there are no more known dinosaurs living on this planet, dinosaurs are considered to be extinct. If a dinosaur is found to actually be living in some exotic part of the world, then that species will be removed from the extinct list. This can also apply to modern animals, like the coelacanth, which was thought to be extinct, but then found again by fishermen in Africa in 1938.

Did early mammals cause the extinction of dinosaurs?

No. By the time the dinosaurs went extinct mammals still played a relatively minor role ecologically. It is generally accepted that an asteroid or comet struck the earth, causing ecosystems to collapse worldwide and resulting the extinction of many groups of animals including the dinosaurs.

Why do scientist believe troodon is the smartest dinosaurs?

The only way for paleontologists to try to determine the intelligence of an extinct animal is to compare its brain mass to its total mass. Troodon had the biggest brain to body mass ratio of any known dinosaur. Judging by brain size, scientists believe that Troodon had the same intelligence level as modern birds.

Why do scientists believe an asteroid collision probably killed the dinosaurs?

The most important feature in this answer will be becausegeologists found a separation in earth segments. Before that line,there were dinosaurs and afterwards no more. In that segment, justa few inches wide, they found high levels of iridium, which wouldprove an asteroid destroyed the Dinosaurs. Also; I would recommendyou to read the dinosaur article on Wikipedia. Especially theparagraph on their extinction. Answer2: Listing some speculations as to what happened to them,Princeton scientist G. L. Jepson stated: "Authors with varying competence have suggested that dinosaursdisappeared because the climate deteriorated . . . or that the dietdid. . . . Other writers have put the blame on disease, parasites,. . . changes in the pressure or composition of the atmosphere,poison gases, volcanic dust, excessive oxygen from plants,meteorites, comets, gene pool drainage by little mammalianegg-eaters, . . . cosmic radiation, shift of Earth's rotationalpoles, floods, continental drift, . . . drainage of swamp and lakeenvironments, sunspots."-The Riddle of the Dinosaur. It is apparent from such speculation that scientists are not able,with any certainty, to answer the question: What happened to thedinosaurs? University of Arizona scientist David Jablonski concludes that 'formany plants and animals, extinction was abrupt and somehowspecial.Mass extinctions are not merely the cumulative effects ofgradual dyings. Something unusual happened.' Their arrival was alsoabrupt. Scientific American observes: "The sudden appearance ofboth suborders of the pterosaurs without any obvious antecedents isfairly typical of the fossil record." That is also the case withdinosaurs. Their relatively sudden appearance and disappearancecontradicts the commonly accepted view of slow evolution. A more recent theory was put forth by a father-and-son team, Luisand Walter Alvarez. Walter Alvarez discovered, outside the town ofGubbio in central Italy, a curious thin, red layer of claysandwiched between two limestone layers in the rock formation. Thelower layer of limestone yielded an abundance of fossils. The toplayer was almost devoid of fossils, leading the geologists toconclude that life suddenly disappeared and that the thin, redlayer of clay had some connection with the extinction. Analysis revealed that the clay was rich in iridium (a metal), 30times richer than the concentration normally found in rocks. Theyknew that such high concentrations of this rare element could comeonly from the earth's core or from sources outside the earth. Theyconcluded that the iridium was deposited by a huge asteroid thathit the earth, causing the sudden extinction of the dinosaurs. After the discovery of the iridium-enriched clay at Gubbio, similardeposits were found in other parts of the world. Did thiscorroborate the asteroid hypothesis? Some scientists remainskeptical. But as the book The Riddle of the Dinosaur acknowledges,the Alvarez hypothesis added "fresh yeast to the study ofextinction and evolution." And paleontologist Stephen Jay Gouldadmits that it could diminish "the importance of competitionbetween species." Commenting on this new theory and the apparently sudden extinctionof the dinosaurs, one science writer admits: "They could shake thefoundations of evolutionary biology and call into question thecurrent concept of natural selection

What do scientist think cause the dinosaurs to become extinct?

We think a huge comet or asteroid killed the dinosaurs. We don't know for sure, but we have evidence. A crater several miles in diameter has been found, with proof of extreme shockwaves meeting up at the exact opposite side of the globe and causing a massive earthquake. The combination of asteroids, shock waves, earthquakes, volcanoes caused by earthquakes, and the ash from all of those forces combined blocking out the sun for years because of its quantity and dinosaurs breathing the ash, the dinosaurs didn't stand a chance. We do not know if it was a chain reaction, such as the ash blocking the sun killing the plants, which starved the herbivores to death, which starved the carnivores to death. Some people believe there was a volcano that blew its top and was so huge, the lava swept across the globe. But I say, if that happened, the lava would have melted all evidence of dinosaurs, bones and eggs, for example. I have seen the massive crater with my own eyes, and so I believe that an asteroid's shockwaves killed the dinosaurs. But, feel free to decide for your self.

Why do scientists believe that dinosaurs are million of years old?

One of the most unrewarding things a scientist (or science writer) can attempt to do is rebut the arguments of Creationists. This isn't because it's difficult to demolish the Creationist point of view, but because meeting anti-evolutionists on their own terms can make it seem to readers as if there are two logical sides to the argument (which, of course, there aren't). Still, the attempts by Creationists to fit dinosaurs into their Biblical world view is a worthy topic of discussion, if only for amusement purposes. Here are some of the main arguments fundamentalists use, and the contrasting views from the science camp.

Why do scientist think the dinosaurs went extinct?

One reason is that there were a lot of fossils in many layers of rock and then suddenly, there are a lot fewer. Also, there don't appear to be many dinosaurs alive today. So, they went extinct. Do you really mean "how" did the dinosaurs go extinct?

What is theorized to be the cause of the dinosaur extinction?

The most likely single cause for the extinction of the dinosaurs is an asteroid impact that occurred around 65 million years ago. The asteroid is estimated to have been around 6 miles wide and struck the Earth off the Yucatan Peninsula in what is now Mexico. All life forms within the vicinity were destroyed. Large amounts of debris were thrown into the atmosphere. The dust clouds engulfed the Earth and temperatures changed dramatically. The dinosaurs and many other animals, including marine and flying reptiles, could not cope with the drastic change, and went extinct. Evidence for this impact is found in an ancient, partially buried crater off the Yucatan Peninsula in Mexico, called the Chicxulub crater, dated to be 65 million years old. There is also a thin layer of iridium within rock layers that also dates back 65 million years. The iridium is significant evidence because the element is rare on Earth but abundant in asteroids. Shocked quartz of the same age has also been found, providing information about the nature of the impact. However, the asteroid impact is not the sole cause of the dinosaur extinction. Prior to the event, scientists think there was already increased volcanic activity which released poisonous gases into the atmosphere and caused global climate change. By the time their nemesis arrived from space, the dinosaurs, among other animals, were already being stressed by the changing climate, loss of habitat and strained food chain.

Why do some scientists think that the dinosaurs gradually became extinct?

It has to do with the food chain. Say if T-Rex are extinct, the animals it eats over-populate and take all the food or water. Slowly, all the animals start to become extinct. Or, if a certain animal becomes extinct, the things it eats over-populate and the things that eat it normally become extinct.

What do scientist think they may have caused dinosaurs to become extinct?

answ2 . Current ideas support the concept of a large bolide landing in the Yucatan Peninsula in Mexico, a place called Chixculub, about 65 million years ago. This bolide was about 10km in diameter, and created a crater of about 180 km diameter. The bolide contained an unusual concentration of iridium, and Ir dust from this impact is found world wide. This produced huge destruction and the increased clouds and particles would have chilled the atmosphere and killed off most life forms. The ones that survived were able to burrow (Tuatara), and of course the sharks. Other possible causes would include great flood basalt events, and these would also poison the atmosphere. There have been several other major catastrophes in Earth history.

Why is it important to understand the cause of the dinosaurs extinction?

Understanding the causes of an extinction can help us prepare for and hopefully prevent a similar situation in the future. The fact that as much as 90% of dinosaur species died out from climate change near the end of the Mesozoic warns us not to allow global warming to get out of hand. Because we know that the death blow to the dinosaurs was the asteroid impact, astronomers keep track of Near Earth Objects, and are formulating plans for deflecting a large asteroid or comet in the event that one heads toward Earth.

What were some reasons people believe dinosaurs went extinct?

We believe that dinosaurs died out because of A.Meteorites,B.Volcanic Eruptions,C.An extremely upscaled natural disaster,D.Disease,E.They saw the meteor and had a huge party and all died of kidney diseases XD,F.Flamingos,G.All evolved to birds,H.Ice Age.

What event caused dinosaurs to become extinct?

The correct answer is that no one knows. A popular theory at the moment is that a large meteor struck the earth 65 million years ago. There is evidence of large meteor strike at a site called Chicxulub, near Mexico. There are alternative theories such a volcanism. There are immense lava flows that date back to the time of the dinosaurs, indicating that volcanic activity was at a peak contributing to a climate change which dinosaurs could not survive. Increased competition for resources from the growing mammal kingdom provides yet another theory. There is evidence for all these theories, so it could just be the combined effect of all these factors that led to the dinosaurs demise.

How do scientists believe that a great flood killed the dinosaurs?

Scientists do not believe that the extinction of the dinosaurs was the result of a great flood. There are still a number of competing theories about the extinction of the dinosaurs although it is clear that there was a large meteor impact in the Yucatan region, which played a role. It may also be that rising carbon dioxide levels and ocean acidity played a role as well. It may be that there were a number of contributing factors, rather than just one single cause. But scientists do not think that flooding was involved. Note that some dinosaurs were aquatic, and would not have been killed by flooding since they already lived in the water.

Why do some scientist believe that dinosaurs were warm blooded?

There are a number of indicators. Some dinosaur fossils show indications of an active lifestyle that a cold-blooded animal is unlikely to have. One dinosaur was found to have had a four-chambered heart, which is also found in mammals and birds, but not in modern reptiles.

What event is believed to have led the extinction of the dinosaurs?

There are many theories as to how the dinosaurs became extinct, from ultraviolet radiation, to diseases or starvation. The one theory that seems most likely is the impact of an asteroid, about 65 million years ago during the end of the Cretaceous Period. This is also known as the K-T extinction, K standing for Kreide (chalk in German, this describes the sediment layer at that time) and T standing for Tertiary (The next geological period). The crater left by the said 'Asteroid strike of doom' is located in The Gulf of Mexico. However another possible impact site is under the Arabian sea and could have been part of a much larger crater, split up by tectonic shifts.

What do scientists believed caused the mass extinction?

Which ones? There were five big extinction events and the causes were from extreme temperature changes due to volcanism, meteor strikes and other causes to causes not well understood, such as massive die off due to ocean condition changes, such as acidification.

How many scientists believe extinction is real?

Essentially all of them. The fossil record indicates that manyspecies that existed in the past are no longer alive. Regrettablysome species that were being monitored in recent decades havedisappeared and numerous species that are also being watched at thepresent are in sharp decline.

What event cause the dinosaurs to become extinct?

No one knows for sure, but there is a good chance that the dinosaurextinction came about as a result of a very large meteor strike onEarth. Such a strike would have filled the air around Earth withdust, blocking a lot of sunlight. Without enough sunlight, plantswould die back, causing many dinosaurs to starve. (They needed tonsand tons of plant material a day to eat.) With a scarcity of plant-eating dinosaurs, the meat-eatingdinosaurs in turn starved to death. Little animals that did not eatmuch mostly have survived.