A new multi-institutional study has uncovered a softshell turtle, “Hutchemys walkerorum,” that existed in what is now North Dakota, around 66.5 million years ago. During the Late Cretaceous period, just before the mass extinction catastrophe, this turtle species was in existence. The discovery expands the knowledge of softshell turtles, especially how the extinction event affected their evolution.
The fossil specimen of the new turtle species
In 1975, a fossil of the new species was found in western North Dakota It was a partial carapace: the backbones of a turtle’s shell. Until 2013, Appalachian State University had the specimen. But it wasn’t until then that serious research into the fossil began, as reported by International Business Times.
They discussed it with Dr. Steven Jasinski, who was a doctorate student at the University of Pennsylvania, and it was taken further. The researchers identified the specimen as Hutchemys based on its structure.
The newly identified turtle is a member of the Trionychidae family of softshell turtles, which includes an extinct species known as plastomenines. During the Cretaceous and Paleogene periods, they were in their peak, which is about 80 to 50 million years ago. Plastomenines first emerge in the fossil record during the Late Cretaceous era around 100 to 66 million years ago.
According to the report, It is only one of the many species that persists deep into the Eocene Epoch: Platomenus thomasii, which is about 50 million years ago. However, the Cretaceous-Paleogene boundary marked the pinnacle of their variety approximately 67 million years ago. Plastomenines shared several features with modern-day softshell turtles. Plastron—the bones that surround the abdomen and stomach area—is more tightly joined together.
There was a noticeable difference between the plastomenine turtles’ plastron and the plastron of other softshell turtle species.
Will Turtles survive climate change?
Exceptionally, only Antarctica has a turtle population. They include sea turtles, terrapins, and tortoises, as well as those that live on land. Turtles have survived many great extinctions, including the one that wiped off the dinosaurs. But people are threatening their future by significantly altering the environment.
Dr. Terri Cleary, currently at the University of Birmingham, undertook a study looking at how turtle diversity has altered through time. She said tracing their diversity from the Triassic 230 million years ago to the Oligocene end 23 million years ago. This extended time period allows them to see how they altered over time and how turtles respond to climate change.
As mentioned by National History Museum, despite the decreasing climate, turtle diversity remained high after the asteroid impact. As the climate issue continues to alter global average temperatures, this may be crucial to the conservation of current species.
“We do have to remember, though, that there is not going to be any strict one-to-one comparison between the past and present, because what is happening today is much more rapid, the present climate is very different to the deep past, and there are a lot of new factors,” said Cleary, as quoted in the report.
One of these is the fact that humans are depleting turtle habitats. The ability to migrate in the past may have allowed turtles to survive under bad settings, but not in the present period.