New fossil discovery rewrites the timeline of lamniform giants
A collaborative team of scientists from multiple universities, including Columbus State University, has identified a new extinct lamniform shark species that pushes the origin of mega-body size deeper into the past. Published in Communications Biology under the title “Early gigantic lamniform marks the onset of mega-body size in modern shark evolution,” the study suggests that the trend toward enormous body size among lamniform sharks began much earlier than previously believed.
From unstudied specimens to a milestone in shark evolution
The researchers examined fossils from the Darwin Formation in Darwin, Australia. These specimens, collected by researchers in the 1980s and long stored in museum collections, had not been dissected for detailed analysis until now. By applying a refined approach to estimating body size from fossil material, the team identified a remarkably large lamniform predator dating to about 115 million years ago. The estimated body length ranges from 6 to 8 meters (19.5 to 26.3 feet) with a weight surpassing three tons, marking the earliest well-supported evidence of gigantic lamniform sharks.
This discovery challenges the long-standing view that giant lamniforms arose in the Late Cretaceous. Instead, the research places the emergence of megabody sharks in the Early Cretaceous (roughly 145 to 100 million years ago), a cooler period that European and North American researchers had not previously linked to extreme body size in these predators.
Analyzing size in a sea of uncertainty
Central to the study was a novel dataset that connected vertebral measurements from modern lamniform species with known body lengths to estimate the size of fossil individuals. Lead author Dr. Mohamad Bazzi (Stanford University) and colleagues, including Dr. Mike Newbrey (Columbus State University) and former student Tatianna Blake, developed a robust method to cross-check how different living species influence body-length estimates when only partial fossils remain. This methodological advance provides a framework for future assessments of enormous ancient sharks and other large marine vertebrates.
Implications for predatory ecology and environmental change
According to Newbrey, the discovery prompts a reevaluation of how environmental and ecological forces could drive megafauna in the oceans. “We need a rigorous method of estimating body size to understand the conditions that favor such growth,” he said. The team’s findings suggest that gigantism in lamniform sharks may have originated under cooler, Early Cretaceous conditions and that large size could have enabled these predators to exploit new ecological niches, potentially in cooler waters that later behaviors in modern giants like the white shark and mako would occupy.
From undergraduate researcher to co-author
The project also highlights the educational impact of faculty-led research. Columbus State University undergraduate Tatianna Blake, who joined the team as a biology student, earned co-authorship on the Communications Biology paper after continuing work with Dr. Newbrey post-graduation. Blake’s journey—from student researcher to a contributor to a major scientific publication—illustrates the structure and mentorship that can shape scientific careers. Blake notes that early, hands-on research helped her see a pathway toward graduate study and a career in marine science.
Future directions and questions
With this new protocol for estimating body size in fossil lamniforms, researchers can better investigate how climate shifts, oceanic temperatures, and ecological opportunities influenced the evolution of giant sharks. The study raises further questions about the adaptive advantages of extreme body size and how such traits affected the role of lamniform sharks as apex predators across deep time. The team’s approach will guide subsequent explorations into megafauna evolution in marine vertebrates and may illuminate broader patterns of how sharks responded to past environmental changes.
