There are many theories on how dinosaurs became extinct from the realistic to the ridiculous. With the many reasons given the most popular one at the moment is the asteriod theory and there are good reasons for this. Scientist know that a huge asteriod hit our planet approximately 65 million years ago which coinsides with the extinction of the dinosaur.We can consider each theory that is given and decide which explanation is more feasible.
There is proof that an asteroid did hit the earth sixty five million years ago. There is proof that the asteroid was over nine miles wide and struck on the tip of the Yucatan Peninsula in the Gulf of Mexico. Asteroids are not rare even today, in reality; they still strike our planet but the size that falls to our planet today is miniscule to what hit the earth 65 million years ago. A nine mile asteroid would have devastated our planet drastically and not merely from the immediate impact but it would also be the aftermath of this collision. It would alter the atmosphere all over the world, it would cause massive forest fires that would burn through entire countries and there would be devastating storms that would take place in the atmosphere. It would cause such poor air quality that anything living out in the open would find it difficult to escape. There would be massive tidal waves from ocean to ocean but the most catastrophic of all, it would eradicate all sunlight from the earth for longer than six months. This would result in the eradication of seventy percent of all life on earth. The only life that would survive a catastrophe such as this would be the animals that could hide out for the duration of this upheaval deep into the earth. Although there is defining substantiation that the asteriod did hit the earth we can assume this is what happened to the dinosaurs. This therory it is a very logical one and one that is widely acknowledged in the field of science.
The Greenhouse Effect
Some people’s have a therory that the extinction of the dinosaurs came from the greenhouse effect. This scenario would be the earth’s atmosphere trapping all solar radiation caused by the collection of gases, carbon dioxide, water vapor, and methane, which allow inward bound light to pass through but absorb heat radiated back from the earth’s surface with no place to escape. In a simpler form this means it would be like a blanket covering the earth where no heat could escape and temperature would rise drastically makeing the earth scorching enough to melt the arctic ice caps. This process would take over a thousand years from start to finish but how does it transmit to the extinction of the dinosaur?
Well, volcano’s can create a greenhouse effect if there is enough activity all over the world this would produce the cause of global warming. Today you would not find such activity in volcanos there was an extreme amount of volcanic activity in the Cretaceous time and this was immediately before the extinction of the dinosaurs. Scientist says that during this era the earth was defaced by volcanic eruptions. Proof of this is found when scientist excavate dinosaur’s fossils at the ground level of the Triassic, Jurassic period and the dirt appears normal but when fossils were found from the Cretaceous period they found a unusual mineral that was only produced by volcanic material such as high levels of sodium or volcanic rock. This is a feasible explanation to the disappearance of the dinosaurs.
Heinrch K. Erban had his own theory as to why the dinosaurs went extinct and when explained it does make sense although there is no proof to substantiate his theory. Heinrch collected a great amount of dinosaur eggs over the years. He noticed dissimilarity in the eggs collected and found that the oldest eggs had a very thick shell and the latest dated shells where very thin. It seemed that the egg shells were getting thinner over millions of years. This would mean that if this was happened it could be that a baby dinosaur would have a small chance of hatching or the immunity to survive. But does this verify that stress caused extinction? If the shells got thinner then we should be asking why?
Actually the answer is basically simple. It is known that some animals don’t stand up to change very well. We know from the fish that we put in a fish tank and from poultry when they are stressed. With fish if there is a change in their water temperature they under go stress, in poultry if they are under stress their egg shells get thinner.The same thing could have happened to the dinosaurs. We see this phenomenon in birds today that go through stress so it’s not such a farfetched proposal. In the dinosaur days there were intense temperature changes that would cause stress and this would certainly cause the thin egg theory. Unfortunately Heinrch could never provide rock-solid proof and again we are left to contemplate the reason for the extinction of dinosaurs.
We have all heard the saying “Only the strong survive” which brings up the therory that even these huge animals just wern’t able to adapt due to the size of their brain. Maybe the dinosaur having small brains would have had an impact on their extinction but can we base the theory of dinosaur extinction on the dinosaurs having small brains? Some people believe this theory to be correct. Ninety nine present of dinosaurs did have small brains. Scientists know this by the dinosaur skull fossils they have found that determine how much space is left for the brain related to the size of the bone structure.
Like all cold blooded animals they are not recognized for decision making but relatively automatic functions. They do not have the capability to plan in advance or problem solve. Based on this being true then it is possible that dinosaurs could have very easily become endangered due to their incapability to cope with the changes that were taking place in their world. This left them powerless to cope with contending life forms which let them gradually fade away into extinction. Logically we can see this theory to be feasible but again there is no solid proof.
Another theory that is bantered around between scientists is the assumption that a Supernova was the fault for the dinosaur extinction. There is absolutely no evidence to support this theory but they still say it was quite probable. A Supernova happens when a star explodes and sends shockwaves out in the energy of radiationjust as the sun creates. This Supernova can destroy anything in its path and anything that escapes the explosion itself would be in the path of deadly radiation. This would kill just about all forms of life on earth. It is not as farfetched as it happens in the Milky Way every fifty years. Again there is no proof on this theory, just assumptions.
There are some theories on the extinction of the dinosaur that are just too far out there to be believed at all and this is one of those theories. Some people have brought up the idea that caterpillars were the cause of the dinosaur extinction by exhausting all plant life causing a shortage of food for dinosaurs. It is true that caterpillars have gone through several stages of evolution during the Cretaceous period and that they were much larger then that what we know today. The conclusion to this theory is that all herbivores became extinct and the carnivores soon followed. This therory is very hard to accept as the reason that dinosaurs became extinct. This is not a consideration in the scientific world or in the layman’s world either.
We all realized that the sun is the giver of life on earth but it can also take life away by the ultraviolet rays that come from it given the right situation. We know that ultra ray is harmful to all living organisms on earth but we have an Ozone shield around the earth that protects us from these harmful rays. But this layer can be damaged by pollution as we well know today with the emissions of factories and automobiles to mention a few causes.
During the time of the dinosaur there were no factories or automobiles so the Ozone layer would be in perfect condition. There was one natural disaster that could have damaged the Ozone layer back then and that was volcanoes. This leads back to scientist digging up dinosaur fossils from the Cretaceous period and also finding a lot of volcanic rock. We know that scientist know there were lots of volcanic eruptions so it is not a far jump to figuring out that this had a very detrimental effect on the Ozone layer.
When a volcano errupts it not only produces lava but it also produces huge amounts Hydrochloric acid. This poisonous gas can deface the Ozone layer. Scientists know there were mass amounts of active volcanoes during the Cretaceous period. This could have spread cancer like wildfire with no protection from the sun. Dinosaurs did not have any protection like birds and other creatures who had the protection of feathers so they would be left totally endangered by the activity. This would have been the beginning of the end for the dinosaur. This again is just a theory. Well, maybe a little proof as we do know there were massive volcanic eruptions.
These are just a few of the theories that are being discussed but we have to base our decision on the facts that are available today and the fact it that an asteriod would have wiped out the dinosaur. in the world today the quest to find out how dinosaurs did become extinct will not end in pursuit of the truth. We may never know the answer for sure but you can be sure there will be new theories introduced, as long as mankind seeks theories on how dinosaurs became extinct.