Friday, October 5, 2012

World's biggest dinosaurs



With fossil brush in hand, we unearth the massive behemoths that ruled over land, air and sea millions of years ago



Stegosaurus
Stegosaurus was 
Slightly larger than a shipping container, but its brain was only the size of a walnut.






Brachiosaurus

The brachiosaurus used its staggering 16m (52.5 feet)

Height to reach
Tall vegetation.


Pterosaur
The hollow bones of a pterosaur ensured it remained light
Enough to achieve flight,
Even when reaching the size of a small plane.
 

     

It’s somewhat frightening to
Imagine what it must have been like to wander around the plains
Of Africa and Argentina 100
million years ago. Whereas today you’d be hard-pressed to encounter a beast any bigger than yourself, back then you’d be running for your life as bus-sized creatures roamed free, some remaining largely peaceful and distant, others full of aggression.
The biggest land-based animal alive today is the African bush elephant, with the largest weighing a measly 13.5 tons and measuring io.6m (34.8ft) long and 4.2m (13.8ft) high. Argentinosaurus, the current of facial
Record-holder for largest dinosaur of them all, would have been at least four times the size. It was a sauropod, dinosaurs of the Jurassic and Cretaceous period that were mostly
Herbivores and known for being very large. Indeed, many other types of sauropod would have stood tau above the African bush
Elephant, as would carnivores, raptors and pterosaurs (‘flying dinosaurs’).
0f course, the dinosaurs inhabited the Earth for much longer than any modem
Animal, from 251 to 65 million years ago, allowing plenty of time for certain species to develop into the giant hulks of flesh we now so revere. The biggest dinosaurs discovered to date have largely been determined to live in the Late Cretaceous period, 99.6-65.5 million years ago, before they faced extinction.
For a long time, though, paleontologists have wondered why dinosaurs grew to be so large. While impressive, size can also be a hindrance. Not only does a large animal need 

   

     A much higher rate of metabolism, but it must also develop much stronger bones and

Skeletal structures to be able to hold itself upright. Many of these gigantic animals were also cumbersome and slow, leaving

themselves open to attack from large
Predators. Why did dinosaurs continue to grow for millions of years, then?
One train of thought is that there was a huge surplus of carbon dioxide in the
atmosphere during the age of the dinosaurs. This meant that vegetation flourished, and herbivores such as the sauropods simply had an over-abundance of nourishment available to eat. While somewhat of a burden in terms of manoeuvrability, their size would certainly have helped to some extent when fending off smaller carnivores. This leads to another proposal from palaeontologists, namely that some dinosaurs grew in size over millions of years as a form of self-defense.
However, others think that these giant dinosaurs were cold-blooded, which was directly responsible for their size. indeed, warm-blooded animals simply wouldn’t be able to sustain such mammoth sizes,
Somewhat backed up by the lack of
mammals larger than a few tons today.
Huge cold-blooded sauropods, weighing in at up to 100 tons, would have been almost self-sustainable, as they could store heat throughout the day for the colder nights, maintaining a fairly unchanged body
temperature and prolonging their survival.
Turn over for our look at the truly
humongous beasts that would wreak endless havoc if they roamed our planet today.

0 comments:

Post a Comment

Share

Twitter Delicious Facebook Digg Stumbleupon Favorites