Hmmm well lot of them always think if thousand of years ago, there were huge creatures, nearly 100 feet high ruling the earth, then where are they now ? Also to be precise there lived human giants, the longest or the tallest was 32 feet tall (gosh if I were tall like that I wud have squashed Yao Ming lol). The thing to be noticed here is everything in prehistoric times was huge. The reason for their extinction is not clearly explained by scientists till now. Some of the reasons which they have given are explained below:
1. Asteroids or Volcanoes?
Approximately 65.5 million years ago, an event occurred that caused the mass extinction of about 70% of the earth’s animals and plant species in a relatively short geological time period. It is called the Cretaceous-Tertiary extinction event or the K-T extinction event (yea I know what is that don’t worry its just a name so don’t ponder over). A thin band, a geological signature called the K-T boundary, identifies this.
Around the world dinosaur remains (of the non-avian variety) have only been discovered below this K-T boundary. This points to the conclusion that dinosaurs became extinct either right before the event or because of it.
Luis and Walter Alvarez, along with other scientists from the University of California, during the late seventies, were closely studying the K-T boundary in Gubbio, Italy, when they made an interesting discovery. In a clay layer at the boundary point they found 30 times the normal level of a rare element called Iridium (no you can’t make ice cream from that, no). Such high levels of Iridium, it has been theorized, could have only come from two sources: either asteroids or violent volcanic activity
2. The Asteroid
Many in the scientific community have postulated this impact event theory. The theory suggests that a large asteroid fell to earth and created a cloud of dust and other aerosols that blocked the sun’s rays for up to a year. This reduction in sunlight radically affected plant and animal life causing a change of atmosphere. At the time of impact a pulse of intense radiation killed many species and the resulting climate change and global firestorms decimated the rest. Dinosaurs, because of their size, were the first to succumb.
*well before hearing this I wished to see an asteroid in front of my eyes now nope I don’t want to die. mama pls save me gosh I cant imagine a war of the worlds type of a scenario now I wont know where to run, well I don’t want to run and then get hit by an asteroid I would rather get hit by a car and die soon …
3. Volcanic Activity
The Deccan Traps, located in Western India, formed at the end of the Cretaceous period, the same time the dinosaurs disappeared from earth. The Traps are a bi-product of violent volcanic eruptions. This theory postulates that the volcanic activity at the time would have released massive amounts of sulphuric aerosols and ash into the atmosphere again causing a major shift in the earth’s climate. A shift that the dinosaurs were not equipped to survive.
4. Ice Age
Another theory relies on the idea of a major drop in temperature that caused the dinosaurs to die out while allowing the warm-blooded, more insulated mammals to survive. In this case all the plants, animals and marine life that could not adapt to the plummeting temperature became extinct. A number of scientists pair this theory with the asteroid theory, claiming that it was the asteroid that triggered the deep freeze.
5. NEW THEORY
DINOSAURS weren’t just killed off when the asteroid hit, they were struck down in their prime, suggests a new analysis of dinosaur fossils around the world.
“Dinosaurs were just doing incredibly well at the end of the Cretaceous,” says David Fastovsky, a paleontologist at the University of Rhode Island at Kingston.
The first dinosaurs evolved about 230 million years ago in the Triassic period. Early dinosaurs were generalists, and had evolved into no more than around 40 genera at any one time up until the late Jurassic, which began about 160 million years ago.
But then diversity soared in the Cretaceous which followed (see Graphic). Fastovsky’s team has established that at least 245 dinosaur genera lived during the late Cretaceous period, from 65 to 99 million years ago (Geology, vol 32, p 877). “The lifestyles of dinosaurs became much more diverse,” says Fastovsky’s colleague Peter Sheehan of the Milwaukee Public Museum. “By the late Cretaceous, we had much more specialized animals.” The diversity of plant-eating dinosaurs in the period is “absolutely breathtaking”, he told New Scientist. For example, hadrosaurs evolved an elaborate duck-billed jaw filled with teeth to chew vegetation, and the rhinoceros-like ceratopsians evolved elaborate horns.
Earlier studies had suggested dinosaur diversity dropped shortly before the asteroid impact, based on a drop in the number of genera uncovered from the two final stages of the Cretaceous, the Campanian and the Maastrichtian. The new data also shows a slight decline between those two stages, but statistically this difference is meaningless because very few dinosaurs are known from other stages of the late Cretaceous.
There are many plausible explanations and scientific theories regarding the extinction of the dinosaurs. New scientific evidence is discovered all the time, which supports one hypothesis or another, however, the truth is that we really don’t know what ended the reign of these giants of the prehistoric world.
Well what ever made them die should be thanked by us simply because i don’t want to get squeezed by a dinosaur for that matter eaten up… cant imagine!
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