When some people look at dinosaurs, they either see them as big, dumb plant-eaters—kind of like giant cows—or they see them as ferocious meat eaters that devoured their dinosaur brothers. While both of these extremes are somewhat true in their own respect, they don’t paint the entire picture. In reality, the dinosaur’s diet was probably much more complex than you would imagine.
So what did the dinosaurs eat? Well, most of the different species of dinosaurs that lived probably were plant eaters. These dinosaurs had flat teeth that were good for not only stripping trees of their leaves but also for grinding down fibrous plant matter. These herbivores probably also ate a variety of other things to supplement their diets, such as twigs and seeds. And some scientists speculate that these plant-eaters probably consumed stones as well. Just like modern birds. These stones would help their stomachs grind down the plant material further so they could extract the nutrients from it.
You can tell what the carnivores like T-Rex and Velociraptor ate just by looking at their teeth. These dinosaurs had long, serrated teeth that was designed for one purpose and one purpose alone: ripping flesh from the bones of other dinosaurs. This would have made these animals the apex predators of their time. However, not all scientists believe that these carnivores were indeed hunters. Some believe that they were actually scavengers. Eating the flesh of dinosaurs that have died from natural causes, or stealing the eggs of other dinosaurs. While neither explanation has been fully proven, the truth is probably somewhere in the middle. These dinosaurs probably hunted and scavenged to meet their caloric requirements.
What is often overlooked by people is the fact that there were some dinosaurs that probably ate both meat and plant materials. These dinosaurs would have had some teeth that were capable of tearing through flesh and some teeth that were capable of grinding up plant material. Omnivorous dinosaurs that ate both include Nothronychus, Hagryphus, Beipiaosaurus, Yunnanosaurus, Citipati and Nomingia. These dinosaurs not only ate plants and meat that they scavenged, but also quite likely feasted on a variety of different insects.
Which brings us back to our original question. What did dinosaurs eat? Well, as you can clearly see it all depended on what type of dinosaur they were and what type of teeth they had. Plant eaters probably lived on a variety of leaves, twigs and seeds which would have included conifers, geiko plants, redwoods, yews, pines, cypress and cycades. They may have also eaten a variety of angiosperms and other flowering plants. Meat eaters, on the other hand, probably not only lived off the carcasses of dinosaurs they either hunted or scavenged, but also probably fed off of insects. Omnivores probably lived off whatever was readily available—whether it was animal, vegetable or insect.