Big Al the Allosaurus

NOTE:  Click on "Free Printable Downloads and scroll down to see the names of the drawings you can print to color.  The most recent drawing is this one of Big Al the Allosaurus.  The older drawings are farther up the list.  For more information on all of the dinosaurs scroll down on the blog post and keep hitting "Older Posts" to see what I wrote about T. rex and Torvosaurus in the past. 

Big Al the Allosaurus

Big Al is the name they gave to a dinosaur that they found that had been a bit of a klutzasaurus.  He stubbed his toe...or more accurately, he broke his toe.  For a predator that was a fatal injury.
He was found in what in the Jurassic Period was a riverbed.  He probably starved to death and ended up happening to die in the riverbed.  When the rainy season came he was buried in sediment so his bones were covered up and fossilized and preserved. 

Allosaurus was a top predator of the Jurassic Period.  They had an eyebrow crest over each eye.  They also had sharp serrated teeth and three larger claws on each rather large arm.  So, unlike the much later T. rex, they could claw and grasp their prey. 

The Cleveland Lloyd Quarry near Price, Utah has many of their bones, possibly indicating that they lived and hunted in packs.  Perhaps Big Al was a "lone wolf." and so when he was injured there was no help from a pack.

A similar story but with a happy ending was the story of Sue the T. rex who had a broken leg but lived through the 6 weeks it took to heal.  Also evidence that T. rex also hunted in packs.  Her pack took care of her.... or at least her mate took care of her...fed her...so she lived to hunt again.

There is evidence that some Allosaurs grew to up to 40 feet or 12 meters or so long.  They were not as heavily built as the much later T. rex.  They weighed at most around 4 tons.  Still, only the somewhat more robust Torvosaurus was bigger.  In fact, Torvosaurus had a much larger nearly T. rex size skull and Allosaurus had a smaller skull. Allosaurus' skull was about 1 yard or 91 cm long.  In comparison the Torvosaurus had a skull that was about 52 inches or 1.32 meters long.

Allosaurus is perhaps the most well known of all Theropod dinosaurs.  There have been many Allosaur skeletons found. The BBC made a very good documentary about Big Al and his short life. It is thought that Allosaurs lived for over 30 years, but Big Al, because of his broken toe, lived only into his teens.

Allosaurs by a River

Torvosaurus and Rhamphorhynchus

Notice the larger skull. 

T. rex drawing from Skull  (for comparison) 

Notice the even larger skull. 

Tyrannosaurus rex

Note that T. rex had better binocular vision than Allosaurs.  An Allosaurus had only about a 20 degree section of its field of view that was binocular vision. By the way, we really don't know what color or pattern was on dinosaur scales.  .  . but since modern reptiles, birds, amphibians, and mammals come in a variety of patterns I do a variety of patterns on my dinosaur drawings.