The Largest Dinosaurs...

The Age of Dinosaurs ended millions of years ago but paleontologists are still attempting to get a handle on the immense diversity and diverse immensity of these creatures.

Take the report last month that Spinosaurus is now officially the biggest carnivorous dinosaur known to science. This two-legged beast actually strode onto the fossil scene in 1915 when a specimen was described by German paleontologist Ernst Stromer. He figured this theropod (defined as a two-legged carnivore) was bigger than Tyrannosaurus rex, but the original Spinosaurus bones were destroyed by Allied bombs in 1944. So the T. rex reigned as the king size, carnivorous land beast for decades.

Then along came Giganotosaurus 11 years ago.

The Type Of Carnivors...

Spinosaurus
Length: 55 feet

Weight: 8 tons

Fear factor: long, crocodile-like jaws

Lived: 100 million years ago

Where: Argentina, Morocco, Tunisia, Algeria

Giganotosaurus
Length: 47 feet

Weight: 8 tons

Fear factor: 8-inch-long serrated teeth

Lived: 95 million years ago

Where: Argentina

Tyrannosaurus rex
Length: 40-50 feet

Weight: 6 tons

Fear factor: teeth up to 13 inches long

Lived: 65 million years ago

Where: North America

For the ultimate in dinosaur length though, a vegetarian diet prevailed. Herbivorous sauropods dwarfed carnivorous theropod dinosaurs, and most scientists think Argentinasaurus was the longest of all dinosaurs.

Argentinasaurus
Length: 120 feet

Weight: 100 tons

Fear factor: get out of my way

Lived: 65 million years ago

Where: South America

(not to scale)