Reconstructing Vertebrate Paleocolor

Abstract

Melanin and other pigments are now well known to be important in exceptional preservation of soft tissues in vertebrates and other animals. Because pigments confer coloration and even structural colors, they have opened a new field of paleocolor reconstruction. Since its inception about a decade ago, reconstruction of color patterns has been performed on several vertebrates, including feathered and scale-clad dinosaurs. Iridescence and other types of structural color can also be identified through melanosome shape and arrangement. How pigments and melanosomes fossilize and are altered has become an important research subject. Ancient color patterns that may range from crypsis to brilliant displays have revealed insights into the evolution and escalation of visual systems, the nature of ancient animal interactions, and how several unique characteristics of birds already arose among dinosaurs. Melanin and other pigments preserve in exceptional fossils; this opens paths for reconstructing coloration of extinct organisms, such as dinosaurs. The most abundant pigment is melanin, which can be identified chemically and through preserved melanosome microbodies. Melanosome shape reveals clues to original hue ranging from reddish brown and black to gray and structural coloration. Other pigments may preserve, such as porphyrin pigments in theropod dinosaur eggshells. Fossil color patterns contribute new insights into the evolution of visual systems, predator-prey interactions, and key innovations.