A groundbreaking discovery has emerged from the dusty plains of New Mexico, where an international team of researchers has identified a new species of duck-billed dinosaur. This revelation, announced by a collaboration that includes a biologist from Penn State Lehigh Valley, reclassifies a 75-million-year-old fossil previously thought to belong to a different dinosaur. The newly identified species has been named Ahshiselsaurus wimani, paying homage to the region where it was first unearthed in 1916.
The team, working alongside the New Mexico Museum of Natural History & Science, published their findings in the Bulletin of the New Mexico Museum of Natural History and Science. The discovery was made possible through a fresh analysis of fossils found in New Mexico, shedding new light on the diversity of the herbivorous duck-billed hadrosaurid family.
The Significance of the Discovery
This new species, Ahshiselsaurus wimani, joins the hadrosaurid family, a group known for its abundance during the Late Cretaceous period in North America’s Western Interior Basin. These dinosaurs were among the most prevalent herbivores of their time, dominating the landscape for approximately 20 million years.
According to Sebastian Dalman, a paleontologist at Montana State University and lead author of the study, the holotype specimen consists of an incomplete diagnostic skull, several isolated cranial elements, and a series of articulated cervical vertebrae. “Hadrosauridae, a family of large herbivorous dinosaurs, were among the most abundant dinosaurs of Late Cretaceous terrestrial ecosystems,” Dalman noted.
“The holotype specimen consists of an incomplete diagnostic skull, several isolated cranial elements including the right jugal, quadrate, dentary and surangular, and a series of articulated cervical vertebrae.”
Revisiting Historical Classifications
The discovery of Ahshiselsaurus wimani challenges previous classifications. Originally identified in 1935 as a specimen of the hadrosaurid genus Kritosaurus, this fossil has now been recognized as a distinct species. D. Edward Malinzak, assistant teaching professor of biology at Penn State Lehigh Valley, explained the significance of this reclassification.
“Kritosaurus is still a valid genus with species of its own,” Malinzak stated. “We took a specimen that was lumped in as an individual of Kritosaurus and determined it had significantly distinct anatomical features to warrant being its own genus and species.”
The research team conducted a detailed anatomical and morphological comparison of the specimens against other fossils in the hadrosaurid genera. This meticulous work led to the conclusion that the specimen’s unique features justified its classification as a new species.
Methodology and Expert Insights
The process of identifying Ahshiselsaurus wimani involved a comprehensive phylogenetic analysis, a method that uses available data to predict evolutionary relationships among species. This approach is crucial for understanding how different species are related and how they evolved over time.
Anthony Fiorillo, co-author and executive director of the New Mexico Museum of Natural History and Science, emphasized the importance of skulls in identifying species differences. “As a general rule … skulls are really the basis for identifying differences in animals,” Fiorillo explained. “When you have a skull and you’re noticing differences, that carries more weight than, say, you found a toe bone that looks different from that toe bone.”
“When you have a skull and you’re noticing differences, that carries more weight than, say, you found a toe bone that looks different from that toe bone.”
Implications and Future Research
The identification of Ahshiselsaurus wimani not only enriches our understanding of the diversity of the hadrosaurid family but also highlights the dynamic nature of paleontological research. As new technologies and methods become available, the potential for re-evaluating existing specimens increases, offering fresh insights into the prehistoric world.
Looking ahead, the team plans to continue their research, exploring other fossils that may have been misclassified in the past. This ongoing work promises to further unravel the complex history of dinosaur evolution and enhance our understanding of the ecosystems they inhabited.
The discovery of Ahshiselsaurus wimani serves as a reminder of the ever-evolving nature of science, where each new finding builds upon the foundations laid by previous research, continually reshaping our understanding of the natural world.
