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Author Topic: What made the dinosaurs become so big?  (Read 1616 times)

Offline chris

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What made the dinosaurs become so big?
« on: 20/09/2013 09:59:03 »
What aspects of the prevailing conditions during the evolution of the dinosaurs made them become so big? Could this happen again?


 

Offline CliffordK

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Re: What made the dinosaurs become so big?
« Reply #1 on: 20/09/2013 12:52:28 »
Warmer weather and higher carbon dioxide in the air likely led to more plant growth and more moisture 100 million years ago (expansion of the tropical environment).  This would have led to an environment that was favorable to larger herbivores, as well as larger carnivores, and an "arms-race" of bigger is better.

Humans have been busy in reversing the multi-million year cooling trend, as well as replenishing the critical shortage of atmospheric carbon dioxide.

And to some extent, it has been working.


http://www.foodpolitics.com/2011/05/whats-going-on-with-human-height/

Perhaps there will be a return of the "dinosaurs". 

Notes I'm seeing is that there hasn't been a homogeneous height increase, but perhaps there is a correlation between global temperature and human height, but also in particular, food supply and height.
 

Offline Don_1

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Re: What made the dinosaurs become so big?
« Reply #2 on: 20/09/2013 13:58:35 »
It has been suggested that the bigger the animal, the more efficient, as far as herbivours are concerned.

When it comes to the carivorous dinosaurs, Spinosaurus, thought to have been the largest carivorous dinosaur (being extant around 112 - 97 million years ago) and and Giganotosaurus, the second largest (100 - 97 million years ago) were larger than Carcharodontosaurus (100 - 93 million years ago) which was larger than Tyrannosaurus (67 - 65 million years ago).

Of the Sauropods, Amphicoelias Fragillimus (around 150 million years ago) may have been the largest of all dinosaurs. Antarctosaurus Wichmannianus (83 - 80 million years ago) may have been the second largest.

So while the sauropods were able to maintain their size, could it be that the theropods were getting smaller?

On the matter of T.Rex, this BBC Horizon programme was very interesting.
 

Offline distimpson

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Re: What made the dinosaurs become so big?
« Reply #3 on: 20/09/2013 15:48:17 »
was not aware of the Giganotosaurus, looks a bit snippy:

 

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Re: What made the dinosaurs become so big?
« Reply #3 on: 20/09/2013 15:48:17 »

 

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