On the Original Diet of Tyrannosaurus rex

The diet of Tyrannosaurus rex seems obvious: it ate meat, right? What if the answer was not that simple?

What did Tyrannosaurus rex originally eat?

If you are familiar with creationist literature, then you might recognize this question. It has been used to illustrate an important concept in the creation narrative, namely that God originally created all animals to eat plants. In Genesis 1:29-30, we are told

And God said, “Behold, I have given you every plant yielding seed that is on the face of all the earth, and every tree with seed in its fruit. You shall have them for food. And to every beast of the earth and to every bird of the heavens and to everything that creeps on the earth, everything that has the breath of life, I have given every green plant for food.”

God spoke these words to Adam and Eve. These verses make it clear that everything, humans and animals, were originally created to eat plants. We can presume that this command changed at the Fall, when death and suffering entered the world as a result of Adam’s sin.

Using this knowledge, the common answer to “What did Tyrannosaurus rex originally eat?” is, it originally ate plants. However, I am going to give a different answer: we do not know what Tyrannosaurus originally ate.


Okay, okay. Before you all get the torches and pitchforks out, let me explain.

Tyrannosaurus belongs to a family called Tyrannosauridae. There are several other dinosaurs included in Tyrannosauridae, including Tarbosaurus, Albertosaurus, Gorgosaurus, Daspletosaurus, Lythronax, Teratophoneus, and several others.

Now, families are significant because it is thought that each created kind at least contains a family. By created kind, I am referring to the “kind” that is repeated throughout the creation narrative in Genesis 1. God created the plants after their kind, the fish after their kind, the birds after their kinds, the land animals after their kind, and so on. Based on how everything was created after their kind, and the fact that plant kinds can be distinguished based on their seeds (verse 12), it appears that kinds represent reproductive units. That is, members of a single kind are capable of interbreeding with each other. To put it another way, a kind appears to denote the entire gene pool of a single type of animal. A single species, like Tyrannosaurus rex, only contains a portion of that gene pool.

A very significant aspect of created kinds is that organisms can change. Natural selection can have an effect on species, but such changes can only operate within the limits of the kind’s gene pool. In other words, we can begin with a single species and it can diverge into a different or multiple species provided that these new species are confined to the genetic diversity outlined by the original created kinds.

Now, we are not told exactly how God created the kinds. Did He create several species at the same time and these species were capable of interbreeding, or did He create one representative pair of each created kind? Either way, there is a strong possibility that God did not create Tyrannosaurus rex directly. Sure, He created one or more Tyrannosauridae species, but considering the number of species in that family, it is possible that Tyrannosaurus rex was not the or one of the original Tyrannosauridae species. That would mean that Tyrannosaurus rex actually arose later, sometime between Creation Week and the Flood. Finally, if Tyrannosaurus rex arose after the Fall, then it is quite possible that it was a meat-eater from the beginning of its species.

I what to make it clear that I have gone beyond the original intent of the question. If the question was altered ever so slightly to become “What did Tyrannosauridae originally eat?”, then I would completely agree that the family, like all original kinds, was originally intended to eat plants. However, we should always pay attention to the fact that the majority of fossils probably came from the Flood, which occurred about 1,600 years after creation. The pre-Flood world that we know of from the fossil record is not the same as the pre-Fall world that God originally created. We can almost be assured that these two world are not exactly the same. That is the sole reason I claim that we do not know what Tyrannosaurus rex originally ate.

Thoughts from Steven.