A fossil was initially interpreted as a plant, but researchers have now discovered it is the lining of a baby sea turtle's shell. The researchers nicknamed the fossil "Turtwig," after the half-turtle, half-plant elf in Pokémon.
From the 1950s to the 1970s, a Colombian priest named Padre Gustavo Huertas collected rocks and fossils near a small town called Villa de Levya. Two of the specimens he found were small, round rocks with veins that looked like leaves, and he classified them as a type of plant fossil. But in a new study published in the journal Palaeontologia Electronica, researchers took a second look at these "plant" fossils and discovered that they weren't plants at all: they were the fossilized remains of baby sea turtles.
"It's really surprising to find these fossils," said Héctor Palma-Castro, a paleobotany student at the National University of Colombia. "These plants were previously described by Huertas in 2003 as Colombian sea turtles. The fossils come from rocks from the Early Cretaceous period, between 132 million and 113 million years ago," he said. The Age of the Dinosaurs. The fossils of Sphenophyllumcolombianum were surprising to have appeared at this time and place—other known members of the genus Sphenophyllum had gone extinct more than 100 million years before." The age and location of the fossils intrigued Fabiani Herrera, assistant curator of plant fossils at the Field Museum in Chicago, and his student Palma Castro.
At first glance, the fossils, about 2 inches in diameter, look like rounded nodules preserving leaves from the plant Sphenophyllum. But Herrera and Palma-Castro noticed something key that wasn't quite right.
"We spent several days searching for plant fossils in wooden cabinets," Palma-Castro said. "When we finally found this fossil, deciphering the shape and edges of the leaves proved to be a challenge. When you look closely, the veins on the fossil don't look like plant veins—I'm convinced they're probably bones."
So he contacted one of his old colleagues, Edwin-Alberto Cadena. He is a paleontologist at the University of Rosario in Bogota, where he studies sea turtles and other vertebrates. Cadena recalled that when he saw the scale of the photo, "I said, 'Well, that's amazing, because not only is this a sea turtle, but it's a specimen of a hatchling, and it's very, very small."
Cadena and his student, Diego Combita-Romero of the National University of Colombia, studied the specimen further, comparing it to the shells of fossil and modern turtles. "When we first saw the specimen, I was very surprised because there were no typical traces of the outside of a turtle shell on the fossil. It was a little concave, like a bowl. That's when we realized that the visible part of the fossil was the other side of the shell, and what we were looking at was the inside of the shell," said Combita-Romero.
Details in the turtle's skeleton helped researchers estimate its age at the time of death. "Turtles grow at different rates and sizes," Combita-Romero said, so the team looked at characteristics such as the thickness of the turtle's carapace and the positioning of its ribs into the solid skeleton. This feature is not common in juvenile turtles, but can be observed in juvenile turtles. All this information suggests that the turtle likely died in the post-hatching stage with its shell slightly developed, between 0 and 1 year old. "
meaning of discovery
"Generally speaking, it's really rare to find fossilized hatchlings," Cadena said. "When turtles are very young, the bones in their shells are very thin, so they can be easily damaged."
The researchers say the rarity of baby turtle fossils makes their discovery important. These turtles are likely relatives of other Cretaceous species that could grow up to 15 feet long, but we don't know exactly how they grew to such huge sizes.
The researchers don't blame Padre Huertas for his mistake—the preserved shells do resemble many plant fossils. But what Huertas thought were leaves and stems were actually modified ribs and vertebrae that made up the turtle's shell. Combita-Romero and Palma-Castro nicknamed the specimens "Turtwig," after the half-turtle, half-plant Pokémon.
"In the Pokémon universe, you encounter the concept of the union of two or more elements, such as animals, machines, plants, etc. So when you discover that a fossil that was originally classified as a plant turns out to be a small turtle, you immediately think of some Pokémon." Palma-Castro said: "In this case, Tur twig, a little turtle with a leaf on its head. In the field of paleontology, your imagination and capacity for wonder are always put to the test. Discoveries like these are truly special because they not only expand our knowledge of the past, they also open a window to many different possibilities."
The scientists also noted the importance of the fossils in the larger context of Colombian paleontology. "We have solved a small paleobotanical mystery, but more importantly, this study demonstrates the need to re-examine historical collections in Colombia. The Early Cretaceous was a critical period in the evolution of land plants, especially for flowering plants and gymnosperms," Herrera said. "Our future work will be to discover the forests that grew in this part of the world."
Compiled from: ScitechDaily