Where Did Dinosaurs Come From?

Fossils show that dinosaurs once roamed over large regions of planet Earth. But where did these enigmatic creatures come from? Most scientists believe that dinosaurs were the product of evolution from more primitive reptiles that lived millions of years before. However, young-earth scientists place the origin of dinosaurs much more recently, with a supernatural act of creation just a few thousand years ago.

The views expressed in this article reflect those of the author, and not necessarily those of New Creation.

The question of where dinosaurs came from has been answered many times before from both points of view. This article will primarily focus on the data and paradigm (interpretive frameworks) used to arrive at those conclusions. These two models of earth history offer very different explanations, yet are based on the same fossil record. The only difference is the paradigm used to tell the fossil’s story.

On the Origin of Dinosaurs

Even though their name means “terrible lizards,” dinosaurs were not lizards. They belonged to a distinct group of reptiles called Archosauria. This group is very diverse and includes pterosaurs (flying reptiles), crocodilians, and a lot of reptiles that looked like dinosaurs, but are missing a few of the key characteristics used to delineate true dinosaurs. Many of these not-dinosaurs resembled a cross between a true dinosaur and a crocodile, like the carnivorous rauisuchians (e.g. Postosuchus). Others, like Lagerpeton and the lanky Silesaurus, were so bizarre that they do not really look like any reptile alive today.

Paleontologists who embrace common descent of all lifeforms believe that archosaurs evolved from common ancestors during the Triassic period. On the old-earth timescale, these common ancestors originated sometime between 251 to 237 million years ago. True dinosaurs did not evolve until the late Triassic period, about 233 million years ago. The earliest known dinosaurs are thought to have been relatively small creatures that walked on two legs originating in the southern hemisphere. Prominent examples include the carnivores Eoraptor and Herrerasaurus, and herbivores like Saturnalia and Pisanosaurus.¹ Even though dinosaurs existed, they did not become dominant lifeforms until the mid-Jurassic period.

The evolutionary narrative for the origin of dinosaurs is partially based on the order of first appearance that different types of animals make in the fossil record. Non-dinosaurian archosaurs like Lagerpeton consistently first show up in rock layers below the lowest layers containing fossils of dinosaurs like Eoraptor. This, combined with the presupposition that all life shares common ancestry, is why the evolutionary explanation for the origin of dinosaurs makes sense to many scientists.

Problems with the Evolution of Dinosaurs

The evolution of life is often depicted as a tree, with a common ancestor at the base and increasingly diverse species branching out over time. If archosaurs evolved through gradual diversification, their fossil record should reflect this tree-like pattern. Their fossil record should begin with a few similar species and progressively diverge into more distinct groups. However, this is not what we observe.

Instead, different types of archosaurs appear abruptly in the fossil record, already possessing the defining traits of their respective groups.² Pterosaurs (flying reptiles) appear abruptly in the fossil record with fully-developed wings, hollow bones, and specialized flight musculature. Crocodile-like archosaurs, such as Hesperosuchus and Sphenosuchus, are found with slender limbs held underneath the body, an elongated skull with sharp, interlocking teeth, and a lightweight, agile body suited for running overland (quite different from modern aquatic crocodiles!). And dinosaurs appear with already erect postures, a modified pelvic structure, and differentiated teeth.

There is little evidence of transitional forms linking them to a common ancestor. This is especially apparent with archosaurs like pterosaurs, which appear abruptly in the fossil record as flighted reptiles. This pattern is known as a “taxic explosion,” of which the Cambrian Explosion is the most well-known. However, taxic explosions are a common occurrence in the fossil record.

Some scientists suggest that archosaurs evolved in a bout of rapid speciation that followed the Permian mass extinction. While extinction events can indeed accelerate diversification (as young-earth scientists propose occurred after Noah’s Flood), the absence of transitional fossils is not evidence for this explanation. Rather, it is an assumption driven by evolutionary presuppositions. In other words, though evolution can be used to explain this pattern, it is neither the expected nor the only possible interpretation of the data.

Welcome to Triassic World

Most young-earth scientists regard fossil layers containing dinosaurs, including those of the Triassic, to have been laid down during the worldwide Flood of Noah’s time. Within this paradigm, the order of first appearance in the fossil record of dinosaurs does not reflect the order in which different types of dinosaurs evolved. Their appearance instead indicates the order in which the different dinosaurs were buried.

It is commonly understood by young-earth geologists that the fossil record represents the successive burial of pre-Flood ecological communities as the floodwaters encroached upon the land. If this is the case, then the Triassic fossil record likely reflects when the floodwaters first invaded the pre-Flood dry land areas. Triassic dinosaurs and other archosaurs were the first archosaurs to be buried in the Flood, not the first archosaurs to evolve.

According to Their Kinds

The Book of Genesis records that God created all land animals according to their kinds on Day 6 of Creation Week. Because most archosaurs were land animals, they also must have been created on this day. While the Bible does not tell us how many kinds of archosaurs (or any other animals) God created, it does seem unlikely that all archosaurs would have been the product of common ancestry. We can attempt to figure out how many created kinds of archosaurs exist with baraminology, the study of created kinds.

A recent study applied statistical baraminology methods to various Triassic archosaurs and identified evidence for distinct groupings that may represent created kinds.³ The analysis found that these animals naturally group into about 16 distinct types, which the researchers believe could represent separately created kinds. One particularly interesting group, called Aphanosauria, were four-legged, lizard-like reptiles, but appear distinct enough from all other archosaurs to qualify as their own created kind. Another group, the Silesauridae, shared many features with each other and were noticeably different from most other archosaurs, except for one, Lagosuchus, which was so similar that it likely belongs to the same kind. A similar pattern was seen with Lagerpetidae, a group of small, agile reptiles that also stood out as their own distinct kind.

Dinosaurs & Pterosaurs

As this study looked primarily at non-dinosaur archosaurs, dinosaurs themselves were not a heavy emphasis for these researchers. However, extensive baraminology research has been performed on dinosaurs elsewhere and shows very clear dissimilarity within the dinosaur group. This suggests that Dinosauria is a group comprised of many different created kinds. Pterosaurs were similar in not being this study’s focus and containing many created kinds within it. Triassic pterosaurs can be broken up into at least four families: Preondactylidae, Campylognathoididae, Dimorphidontidae, and Taeticodactylidae. Even though several species exist within each of these families, this study suggests that Triassic pterosaurs may all belong to the same created kind.

More research needs to be done on all of these reptile groups. However, the emerging patterns seem very consistent with the creationist expectation that there are many distinct created kinds that were not the result of common ancestry. Instead of a singular evolutionary tree of life, we see dozens of different family trees. This is consistent with the independent origins of different created kinds of archosaurs during Creation Week, just as the Bible would have us expect.

Conclusion

Dinosaurs are most commonly understood through the lens of common ancestry by means of biological evolution. At first glance, it is understandable how many scientists would deduce this from the fossil record. However, taking a deeper glance, and using the Book of Genesis as our guide, we see that this explanation is by no means the only or best interpretation of the evidence. Rather, dinosaurs and the other distinct types of archosaurs appear abruptly in the fossil record and do not converge on common ancestors the farther back in time we go. Instead, the emerging portrait suggests independent ancestry for dinosaurs and the other archosaurs in the fossil record, one strikingly reminiscent of what we might expect of supernatural creation by God Himself.

Footnotes

1.  Some researchers think that Pisanosaurus may actually be a relative of Silesaurus, and not a dinosaur at all. ↩︎
2. Brusatte, S. L., Benton, M. J., Lloyd, G. T., Ruta, M., & Wang, S. C. (2010). Macroevolutionary patterns in the evolutionary radiation of archosaurs (Tetrapoda: Diapsida). Earth and Environmental Science Transactions of the Royal Society of Edinburgh, 101(3-4), 367-382. ↩︎
3.  McLain, Matthew A.; Clausen, Caroline; Perez, Thai; Beebe, Katherine; and Ahten, Alia (2023) “A Preliminary Analysis of Archosauromorph Baraminology,” Proceedings of the International Conference on Creationism: Vol. 9, Article 20. ↩︎