Prehistory

Ostriches are a true dinosaur; they have been wandering the earth for at least 70 million years and possibly as many as 120 million years.

Dinosaurs Like Ostriches

Shuvosaurus (SHOO-voh-SORE-us) means "Shuvo's lizard" after the name of  the son of the paleontologist who discovered this dinosaur. It looked like a big ostrich, except that it didn't have feathers. This dinosaur had a short heavy beak that covered toothless jaws. The beak was shaped to crack hard-shelled nuts and seeds efficiently. However, Shuvosaurus probably ate other plant materials as well, along with any small animals it could catch.

Length: 10 feet Weight: 250 pounds Time: 225-220 million years ago Where found: Texas Classification: An ornithomimid or "ostrich" lizard-hip. Notes: The earliest known ostrich dinosaur. Only the skull was found.

Ostrich dinosaur

Although occurrences of the lightly constructed skeletal parts of ostrich dinosaurs are tantalizingly incomplete, they have been recovered from Africa, Asia, Europe, and North America, and span the final 75 million years of the age of reptiles. As with horses, the history of ostrich dinosaurs demonstrates a progressive adaptation to running. Some would have clearly rivaled the modern ostrich in speed. They were possibly the fastest dinosaur of all. Dromiceiomimus, an advanced form, lived in western Canada between 75 and 80 million years ago. Its brain was as large as that of an ostrich, but like most ostrich dinosaurs it possessed long forelimbs which were used to uncover small animals and eggs near the surface of the ground.  

http://www.nature.ca/notebooks/english/dromi.htm

Is the Ostrich REALLY like the PAST?

Ostrich are birds, you say, Well, maybe not! Recent evidence indicates that ostrich, and other members of the ratite family, have a lot more in common with dinosaurs that was previously thought. This evidence blended with the fact that the ratite family has very little in common with other bird species, has caused the scientific community to question whether ostrich are really birds after all!

Perhaps the Chinese know this, long before our modern scientists, for their belief in the mystical, long necked, partially-feathered "dragon" is linked to the ancient medicinal use of fossilized dinosaur bones. It could be that the similarities between the mythical dragon and ostrich are no coincidental because evidence suggests that ostrich lived naturally in China, into time recent enough for their having been hunted and eaten by ancient peoples.

What evidence suggests that ostrich might be misclassified as birds? Ostrich have no keel (the bony plate that protrudes from the sternum of all other birds). It is to this bone that the powerful muscles of flight are attached (creating the breast meat we know in chicken, turkeys, ducks and geese).

It was previously thought that the ostrich "lost" their keel as they evolved, but now there is doubt they ever had one. the ratite sternum is a structure non adaptable for flight, and is of the same sort found in dinosaurs.

Ratite DNA, or genetic material, reveals distant relatedness, at best to other birds.

Ratite sperm differs fundamentally from that of all other birds.

Ostrich skulls are not fused. The skulls of birds are fused into a solid, single structure, that can help protect the brain from mechanical stresses like those during flight, whereas ostrich skulls are dinosaur like, made up of several jointed bony plates.

The upper jaw bones of the ratite are not the same as those in a typical bird. The structural organization of the ratite jaw resembles a condition well-developed in dinosaurs, one that helped move the upper jaw to enlarge gape or mouth opening.

What evidence indicates that ostrich descended from dinosaurs?

Dinosaur like bones and movements. the dinosaur like traits of the ratite skull and upper jaw bone have already been mentioned. It is interesting to note that the fossilized bones of the earliest known ratites (70 million years ago) have been interpreted by some as those of dinosaurs. Not surprising... as ratites and dinosaurs have identically structured leg bones and joints.

Ratite leg bones grow in a manner as did those of dinosaurs and different from those of typical birds. Comparison of tracks left ratites and dinosaurs show that they had like ways of walking and standing.

Trackways made by three-toed ratites correspond with those of most theropod dinosaurs, while examples from the rater two-toed theropod look like those made by ostriches.

Ratites have retained the posture and gait characteristics of dinosaurs for over 180 million years. For this reason, ratites were used to model the movements of the smaller herding dinosaurs in the motion picture, Jurassic Park.

Which dinosaur was a likely ancestor?

Deinonychus: The bones of the dinonychus (145 million years old, central Montana) have over 75 features in common with ratites. It was a powerful kicker (like ostrich) but also a sharp toothed predator (unlike ostrich which eat plants and have no teeth).

Avimimus: A toothless dinosaur that lived over 65 million years ago in present day Mongolia. It's remains show many ratite-like characteristics, most notably the dramatic shortened tail.

Mononychus: From the same era and region as the Avimimus, the fossilized bones of the Mononychus correspond well with those of the present-day ratites, but it had a long tail. Notably, it's small but extremely powerful forearm had fused handbones, like those making up the ratite wing. This strong forearm was tipped by a large stout claw, shaped like those in digging animals. The same claw, albeit much smaller and thinner protrudes in a like manner from the wing or forearm of the ostrich today.

http://www.accessexcellence.org/AE/AEPC/WWC/1995/ostrich.html