The unique discovery allowed paleontologists to find melanosomes—microscopic structures responsible for skin color—in the fossilized skin of a sauropod for the first time.
The study of skin fragments from a Diplodocus in Montana revealed that the three-dimensional preservation of the samples is so good that impressions of these organelles have been preserved. This provides a rare opportunity to get closer to unraveling the true coloration of giant dinosaurs.
The analysis identified traces of two different forms of melanosomes: some were elongated, while others were rod-shaped. Researchers were particularly intrigued by the unusual flat, disc-shaped structures, which are also presumed to be melanosomes. Such a shape in the modern world is often associated with light reflection and iridescent coloring; however, the researchers do not yet claim that the Diplodocus was iridescent.
The discovery shows that Diplodocus had complex skin with diverse scales and could produce more types of pigments than previously thought. This brings them closer to modern birds and mammals.
Lead author Tess Gallagher notes that this work is just the "tip of the iceberg," and further study of the skin of other sauropods may yield new discoveries.
