A newly discovered fossil fish, Romundina gagnieri, shows teeth growing on the bony plates in its mouth. This finding pushes back our understanding of when teeth in jawed fish first appeared. It offers fresh insights into how teeth and jaws evolved together, reshaping theories about vertebrate evolution.
Researchers found fragments of this fish’s skull in Arctic rocks in Canada. These rocks date back about 400 million years. The pieces were uncovered on Prince of Wales Island, an area that was once under the sea. Despite the passage of time, this fossil provides rare insights into early jawed mouths.
Dr. Sebastien Olive from the Royal Belgian Institute of Natural Sciences studied the fossil. He noted that the tooth plates developed as the fish grew, with teeth appearing in a widening pattern rather than just from one area. This challenges the long-held belief that teeth mainly grew from the back of the mouth.
The fossils tell us that early teeth may have not only been functional but also evolved in a more complex way than previously thought. This finding supports the idea that jawed fish may have had varied feeding strategies much earlier than we believed.
The growth of these teeth indicates that as fish evolved, they could better grip, slice, and crush their food. Different shapes and patterns in teeth allowed them to adapt to various diets. “This opened up new food sources for our ancient ancestors,” Dr. Olive explained.
Moreover, the study showed tiny structures called odontodes—mineralized bumps—layered over some teeth. These made even the eating habits of these early fish more interesting, suggesting an evolution that considered survival under diverse conditions.
For years, scientists debated whether teeth developed from external skin or within the mouth. Recent studies have leaned towards the latter, and Romundina supports that view by showing a unique pattern of tooth growth. The significance of this species goes beyond just teeth; it provides a lens into how early jawed fish lived and thrived.
By studying Romundina, scientists may uncover more about the evolutionary history of fish. This fish reinforces that some traits date back much further than previously thought. As additional discoveries are made, we can learn even more about the fascinating journey of jawed vertebrates.
For a deeper understanding of this research, you can consult the full study published in Royal Society Open Science.
