As cryptozoologist Dale A. Drinnon has already pointed out on his blog, these lizards probably belong to the genus Iguana. That is because they share many features with members of that genus, such as a row of spiny scales going down the back, folds of skin above and below the head, and a circular boss near the base of the lower jaw. However, there are only two known species in the genus Iguana alive today, both of which are almost exclusively herbivorous. And it is apparent to me, from at least two reports, that these lizards are formidable predators.
Lon Strickler has written a post on his own blog about sightings of these large unknown reptiles in the Four Corners region of the southwestern United States. In the post, he mentions a report from a woman who claimed that she saw one of these bipedal lizards jumping up into the air, and catching a bird in its jaws. It then proceeded to eat its prey. Another person claims that their uncle's pit bull dog was killed and devoured by one of these creatures.
And finally, the late Fortean investigator John Keel once wrote that, around the year 1970, a man driving a pick-up truck in Texas was attacked and eaten by a medium-sized, bipedal predatory dinosaur. I am very skeptical of this story, since it sounds a lot like a tall tale. However, the other two reports of predatory behavior sound very credible, and I currently cannot think of any reason to discount them.
Therefore, it is my opinion that these iguanid lizards are not herbivorous, like other members of their genus. Instead, they appear to incorporate much more animal matter in their diet. At first, it may seem unlikely that members of the same genus could differ so much from each other in their eating habits. However, a little bit of research shows that it's not as unlikely or as outrageous as it might seem.
There is nothing special or different about the jaws and teeth of lizards in the genus Iguana that prevents them from eating meat. Indeed, the teeth of iguanas are almost identical in shape and structure to those of collared lizards. However, while iguanas are mostly herbivorous, collared lizards are ferocious carnivores that will eat just about any other animals they can find, including other lizards.
Also, in omnivorous species, the amount of animal matter that is eaten relative to plant matter varies widely, even within members of the same species. For example, some human populations are almost vegetarian, while others feed almost exclusively on meat.
And finally, these unknown reptiles, according to the reports, live in a very different habitat than their smaller cousins. Common iguanas are arboreal, but the evidence appears to suggest that these giant iguanas are cursorial animals, built more for running, rather than for climbing.
Therefore, it is clear to me that the supposed predatory diet of these large bipedal iguanid lizards is not so far-fetched, after all.
In my next post, I will discuss the habitat and geographical range of these unknown lizards, and try to locate the places where they are most likely to be found.
Until then, cheers!