Ancient Sea Reptiles were Black, Researchers Say

Huge reptiles that lived deep in the oceans during the Age of the Dinosaurs were black or partially dark-colored, a new study has found.

The study, conducted by researchers at Lund University, analyzed the pigment present in the fossilized skin of ancient reptiles and found that most of them were black or nearly-black colored. The coloration probably helped these creatures regulate their body temperatures, prevent UV damage and helped them hide.

The soft tissue used in the research was from a 55 million-year-old leatherback turtle, an 85 million-year-old mosasaur and a 196 million-year-old ichthyosaur, according to a news release.

Previously, research on skeletal specimens from these reptiles had found "masses of micrometre-sized, oblate bodies." Researchers had then assumed that these bodies were decomposing skin of dinosaurs. However, the latest study shows that these massive spots on the reptiles' skin are actually pigment-containing organelles (fossilised melanosomes).

"Our results really are amazing. The pigment melanin is almost unbelievably stable. Our discovery enables us to make a journey through time and to revisit these ancient reptiles using their own biomolecules. Now, we can finally use sophisticated molecular and imaging techniques to learn what these animals looked like and how they lived", said Per Uvdal, one of the co-authors of the study, from the MAX IV Laboratory.

The Really Old Turtle

The leatherback turtles- weighing in at 2,000 pounds- are still around today. Both their ancient cousins- the Mosasaurs and ichthyosaurs died during the Cretaceous Period.

An important feature of the leatherbacks (Dermochelys coriacea) is that it has a completely black back. Researchers had previously believed that the tuirtles' gigantic size allowed it to survive cold climate. However, now scientists have found that the dark back helped it absorb heat faster and gain a higher body temperature.

"The fossil leatherback turtle probably had a similar colour scheme and lifestyle as does Dermochelys. Similarly, mosasaurs and ichthyosaurs, which also had worldwide distributions, may have used their darkly colored skin to heat up quickly between dives," Johan Lindgren, one of the study researchers, said in a news release.

Modern sperm whale too has a similar color scheme, researchers said. The pigments might help the whales hide in deep, dark waters and might even protect the mammals from UV damage when they surface. 

Inspired by Jurassic Park                 

Johan Lindgren said that he was inspired by the movie Jurassic Park.

"This is fantastic! When I started studying at Lund University in 1993, the film Jurassic Park had just been released, and that was one of the main reasons why I got interested in biology and palaeontology," Lindgren said.

The study is published in the journal Nature.