A new study by Princeton and Yale Universities has revised the timeline of dinosaur origins, pushing it back by 10 million years. This means that dinosaurs are even older than previously thought.

As some of the most memorable and ferocious creatures in history, we know a lot about dinosaurs, including that they encompass around 900 genera and 1,000 species. However, paleontologists continue to uncover more information about them, such as when they first came into existence.

Previously, paleontology pinpointed the emergence of dinosaurs as having occurred over 230 million years ago. However, the evolutionary history of early dinosaurs has remained largely uncertain, according to authors of a new study published in Proceedings of the Royal Society B. By analyzing existing data, they determined that dinosaurs emerged 10 million years earlier than previously understood.

The mysterious origins of the dinosaurs

Researchers thoroughly analyzed nine different morphological datasets related to the three major dinosaur lineages: theropods, sauropodomorphs, and ornithischians. They compiled all available data on dinosaur anatomy, individual traits, and the various sub-groups within the species, demonstrating the exceptional diversity of dinosaurs.

Additionally, the study authors aimed to understand the relationships among different species, recognizing that these species did not exist in isolation. Nature is interconnected, with predatory and prey relationships influencing evolution. By compiling data on the ages of fossils and cross-referencing older evolutionary models, they sought to clarify a previously murky area of research: how old are dinosaurs?

The authors of the study now estimate that dinosaurs first emerged between 250 and 240 million years ago. As noted by Phys.org, this emergence was followed by the rapid appearance and diversification of all major dinosaur lineages.

The study authors described this research as providing “a biological explanation for the instability surrounding early dinosaur phylogeny.”

“The patterns that we infer align with expectations under a scenario of evolutionary radiation, where ecologically diverse lineages rapidly diversify from a single common ancestor,” the study states.

Evolutionary radiation, the latest

A “consensus” is currently building in this field of research. Many of the most diverse lineages of animals and plants alive today originated during periods of “evolutionary radiations,” which refer to rapid increases in the number of species within a lineage.

“Our results provide a biological explanation for the instability surrounding early dinosaur phylogeny and suggest that dinosaur diversity has been shaped by multiple rapid radiations following successive mass extinctions throughout deep time,” as stated in the study.

Based on the latest research, dinosaurs suddenly diversified during the late Triassic period, which was previously understood to be their initial appearance. In reality, this period marks their diversification, as they first emerged a full 10 million years earlier.

“Ultimately, our results imply that the evolutionary history of dinosaurs has been driven by sporadic bursts of morphological evolution throughout their 240-million-year history. At least two of the three major mass extinctions during this time appear to have directly triggered significant bursts of diversification in dinosaurs,” concluded the researchers.

Paleontologists have filled a gap in research, shedding light on some of the most unforgettable creatures that ever lived.