Paleontologists have discovered a Jurassic fossil tail, which could be the missing link in the family tree of crocodiles.
During the Jurassic period between 200 to 145 million years ago, ancient crocodiles had two basic forms. One group had dino-like armor and used limbs for walking on land. The other group was more dolphin-like, having tail fins and flippers and no armors.
Researchers said that the 180 million-year-old fossil belonged to an intermediary species that featured both armor and tail fins.
"This fossil provides a unique insight into how crocodiles began evolving into dolphin and killer whale-like forms more than 180 million years ago," said Mark Young, from the University of Edinburgh's School of GeoSciences.
The researcher said that the presence of both the tail fin and bony armor shows the remarkable diversity of crocodiles during the Jurassic period.
Young and colleagues, who dug up the tail in a mountain in Hungary in 1996, called the new species Magyarosuchus fitosi after Attila Fitos.
Odd-Looking Vertebra Features
Scientists distinguished the fossil to be different from other species because of an odd-looking vertebra that formed part of the creature's tail fin.
In a study published in the journal PeerJ, Young and colleagues described the species that featured pointed teeth that were likely used for grasping prey and a body measuring 5 meters long.
"The unique combination of retaining heavy dorsal and ventral armor, while having a slight hypocercal tail, on the other hand, highlights the mosaic manner of marine adaptations in Metriorhynchoidea," the researchers wrote in their study.
Virtually Untouched By Evolution
Crocodiles are unique creatures in that they barely changed over the course of millions of years. Unlike most animals that live today, these prehistoric-looking creatures remained virtually untouched by major evolutionary changes for at least 8 million years.
"If we could step back in time 8 million years, you'd basically see the same animal crawling around then as you would see today in the Southeast. Even 30 million years ago, they didn't look much different," said Evan Whiting, a doctoral student at the University of Minnesota, who studies crocodiles.
Why Researchers Study Crocodiles And Alligators
Studying crocodiles provide researchers opportunity to study other animals such as to learn how birds may have evolved from dinosaurs and to identify possible characteristics of the now extinct dinosaurs.
Researchers also study alligators and crocodiles to find more effective antibiotic treatments due to these creatures' robust immune system.