How huge? Scientist estimate spinosaurus to be 40 to 56 feet or 12 to 17 meters from head to tail. Spinosaurus? body looks a lot like that of T-Rex, but there are a couple of obvious differences. Of course, T-Rex didn't carry that large sail-like fins made of 6-foot spines. And the front arms of the spinosaurus are heavier and longer than T-Rex's arms. Some scientists think this means that spinosaurus used them for walking, while others say these strong front arms could really get a grip on dinner. The head of spinosaur was longer, more narrow, and not as heavily built as that of T-Rex.

Whoever named this beast wasn't having the most creative day. Spinosaurus means ?spiny lizard.? There were large spines extending from the vertebrae along its back. And when I say large, I mean they could grow up to 6 feet long! Most researchers believe that the spines were covered with a membrane of skin that filled in the spaces between the spines, sort of the way webbing fills in the spaces between the ?toes? of a duck This made a sail-like fin that could have helped control body heat. Some researchers think that the sail could have been extended or collapsed at least to some extent. Perhaps then the sail could be used get some other dino's attention.

Spinosaurus was discovered in 1912 by a German paleontologist. Ernst Stromer found the first and most complete specimen in Egypt. Sadly, this specimen met its demise for a second time during the bombing of Munich in WWII. No spinosaurs since Stromer's first find have been as complete.

The long narrow snout of spinosaurus contained jaws full of sharply pointed teeth. Unlike the steak knife serrations of T-rex teeth, Spinosaur teeth were smooth and round. Because of the resemblance to the bite of crocodiles, where the upper teeth of the spinosaurus interlock with the lower teeth, scientists think spinosaurus might have had a diet consisting primarily of fish. To add weight to the fish diet theory, acid etched Fish scales have been found in spinosaurs stomachs. While their bodies are well-adapted for meat, their particular variety may have been of the swimming type.