An international, multi-university research team, including scientists from Columbus State University, has unearthed a crucial new piece of the puzzle in the evolution of sharks.

A recent study published in Nature’s Communications Biology journal, “Early gigantic lamniform marks the onset of mega-body size in modern shark evolution,” has identified a new, extinct lamniform shark—a group that includes modern-day great white and mako sharks. It marks the earliest known example of a gigantic shark, suggesting that the trend of mega-body size in modern shark evolution began much earlier than previously thought.

The team, led by Dr. Mohamad Bazzi of Stanford University, included Dr. Mike Newbrey of Columbus State’s Department of Biology and 2020 alumna Tatianna Blake. They derived their conclusions after studying specimens from the Darwin Formation that outcrops at Darwin, Australia. These specimens, collected by other researchers in the 1980s, had been stored in a museum collection and remained unstudied until recently, when the team examined them in detail.

By analyzing newly discovered fossil evidence, the group’s conclusions rewrite the timeline of the evolution of megabody-sized sharks as apex predators, pushing it back by 15 million years. The 115-million-year-old fossil vertebrae were used to estimate a body length of 6 meters to 8 meters (19.5 feet to 26.3 feet), and a weight of over 3 tons. The earliest lamniform fossils were small and uncontestably date back to about 135 million years old.

“As a field, we are curious about the environmental and ecological conditions needed to evolve mega-body size,” Newbrey explained. “As researchers, we need a rigorous method of estimating body size to answer the question about the conditions needed to evolve large body sizes in lamniform sharks.”

Newbrey went on to explain that the size estimates used in this study were derived from a novelly compiled and analyzed dataset of vertebrae from 10 species of living lamniform sharks with known body lengths. Prior to this study, there was no way to cross-evaluate the effects of different species on body-length estimates from fossil material, nor was there an informed interpretation of body-length estimates from incomplete fossil material of lamniform sharks.

Previous interpretations suggested that gigantic lamniform sharks evolved in the Late Cretaceous period (100.5 to 66 million years ago) with a specialization in pelagic lifestyles. However, Newbrey said the team’s investigation supports an earlier evolution of gigantic lamniform sharks in the Early Cretaceous period (145.1 to 100.5 million years ago) during a time when it was relatively cooler than the Late Cretaceous period. As a result of this research, the field has a new set of questions to consider in the evolution of gigantic lamniform sharks.

From student to published researcher

In addition to the team’s discovery, the project uncovered another one—Columbus State undergrad Tatianna Blake’s interest in research. Newbrey mentored Blake as part of her undergraduate research project, which she completed as a biology student. Her involvement in Newbrey’s line of research continued after she graduated, which landed her a coveted co-authorship credit in Nature’s Communications Biology journal.

“[T]hat opportunity [to work with Newbrey] alone had a lasting impact on my academic trajectory,” Blake recalled. “The structure of my undergraduate program—which required students to engage in faculty-led research—was instrumental in exposing me to research in the first place. The mentorship I received [from Newbrey] and the hands-on nature of the project itself provided the foundation I needed to appreciate and pursue research further.”

Continuing scientific research wasn’t necessarily on Blake’s radar after she graduated with her biology degree and concentration in pre-veterinary medicine. She instead applied her minor in military and advanced leadership to serving as a U.S. Army logistics officer, and later, teaching high school aquatic science and astronomy. Blake is now focused on being accepted to a doctoral program and conducting research in marine science.

“[Dr. Newbrey’s] passion for ichthyology inspired me to explore fish research myself,” she said of her experience as an undergraduate researcher. “The project, which focused on a lesser-known fossil fish species, quickly captured my interest. It was exciting to work with actual fossil specimens and contribute original data to a field I hadn’t previously considered. That experience sparked a deeper appreciation for research and its broader impact.”

Newbrey said not every project leads to publication in such a prestigious scientific journal, but including students in faculty-led research is a priority for him and his faculty colleagues.

“Students perform best academically, and later professionally, when they have opportunities to apply what they learn by doing,” he said. “We strive to include our students in research opportunities early in their studies, so they can realize the power and potential of how what they learn in the classroom contributes to the science and education fields, while also bettering the communities in which we live.”

Future research applications

Newbrey said this new analysis will be useful to many future studies of lamniform sharks. The new large lamniform predates other giant sharks, and this study provides a protocol to estimate body size for the study of the effects of the environmental and ecological factors that allowed sharks to reach such colossal proportions.

“For example, the team notes that the large cardabiodontid existed during a relatively cold time, and they speculate that large body size may have enabled these particular sharks to survive in colder waters, thereby capitalizing on a vacant niche filled today by other large lamniform sharks,” he said. “Being able to estimate body size from isolated vertebral material will enable us to answer larger questions about shark evolution while considering the effects of climatic change.”

Communications Biology is an open-access journal from Nature Portfolio that publishes high-quality research, reviews and commentary across all areas of the biological sciences. Research papers published by the journal represent significant advances, providing new biological insights into a specialized area of research. 

Along with Newbrey, Blake and Bazzi, the research team and manuscript co-authors include Dr. Mikael Siversson of the Western Australian Museum and Curtin University (Australia), Sabine Wintner of Curtin University and the KwaZulu-Natal Sharks Board based in South Africa, Dr. Jonathan L. Payne of Stanford University, Dr. Nicolás E. Campione of the University of New England, Armidale (Australia), Dr. Aubrey J. Roberts of the University of Oslo’s National History Museum, Dr. Lisa J. Natanson (retired) of the NOAA/NMFS Narragansett Laboratory in Rhode Island, Stephen Hall of Lund University (Sweden), and Dr. Benjamin P. Kear of the Swedish Museum of Natural History.