Ancient Mexicans didn't have cattle, so their sources of proteins were different: turkey, beans, sometimes game, but also snakes, iguana and certain insects such as crickets, agave worms or jumiles.
Even though nowadays most Mexicans don't eat the more "exotic" products, they can still be found if one knows where to look. Therefore, I found the products pictured above in a store in Oaxaca.
I have to say they taste rather good, but I would still miss a good steak.