The Hava Supai Petroglyph Located in Arizona's Hava Supai Canyon, it was first discovered by a prospector named E.L. Dohney in the year 1879. The pictograph measured about a foot high and seven inches wide. It clearly resembles some species of dinosaur, with its long serpentine neck and tail supported by two large feet. The most likely estimates were either an Iguanodon or a Diplodocus.
It was photographed and even had a cast made of it during the 1924 "Dohney Expedition" in which the man it was named after partook. The expedition was led by Samuel Hubbard, who was the Honorary Curator of Archaeology at the Oakland Museum in Oakland, California. A paleontologist was there, and not just any paleontologist, but one associated with the United States National Museum named Charles W. Gilmore, who was then Curator of Vertebrate Paleontology at that institution.
Concerning this find, Hubbard (unlike most establishment scientists) did not dismiss this evidence for man's coexistence with dinosaurs with a mere wave of the hand, nor did he try to assert that this drawing was "misidentification" of an animal that lived during the mythical Ice Age; rather, he admitted honestly that this find undermined "the science" in his report on the expedition entitled
Discoveries Relating to Prehistoric Man:
The fact that some prehistoric man made a pictograph of a dinosaur on the walls of this canyon upsets completely all our theories regarding the antiquity of man. Facts are stubborn and immutable things. If theories do not square with the facts then the theories must change, the facts remain.
(Discoveries Relating to Prehistoric Man, pg. 5 as quot. in Cowboys and Saurians, pg. 399 by John Lemay)
Here is a brief comparison image of the pictograph with depictions of the Diplodocus:
And since those artistic depictions are now considered outdated by modern standards, I will insert a modern illustration that also shows Diplodocus in a bipedal position. Note again the similarities:
This seems to be the most likely candidate for the creature portrayed in the image; Hubbard believed so himself and stated this in his report, going as far to place images of the two side by side, and I find no reason to disagree with him (
Cowboys and Saurians, 339).
Some other details concerning this pictograph is that:
1) There were other pictographs near it that portrayed evidently non-extinct animals such as snakes and goats.
2) Hubbard believed that whoever drew this image must have seen this animal alive due its upright posture.
3) On the edge of the Painted Desert (not far from the canyon) fossilized dinosaur tracks were found, proving that they had been roaming about this area at some point in the past.
I might write another post about this subject, as there is more about it that I'd like to share.