Cork, Ireland – A new study conducted by a group of Irish paleontologists at University College Cork has discovered that some snake fossils can retain evidence of skin color from multiple pigments and structural colors contained in mineralized tissues.
The study published on March 31 in the journal Current Biology reported for the first time that mineralized tissues can preserve evidence of color helping research into the evolution and function of color.
Paleontologists analyzed a 10 million-year-old snake fossil found preserved in calcium phosphate and found that the colors of the extinct snake might still be able to determinate even though it was a colorless fossil.
Up to now, scientists have been limited to browns, blacks, and muddy reds as melanin lasts as organic material, but no other pigments have been shown to survive fossilization making it impossible for the scientist to discover any color different from these. However, this snake’s skin, in particular, was fossilized in calcium phosphate, a mineral that preserves details on a subcellular level giving scientist an extra option.
“When you get fossil tissues preserved with this kind of detail, you’re just gobsmacked when you’re looking at it under the microscope. I was astounded. You almost can’t believe what you’re seeing.” Maria McNamara, the study’s lead author, said in a statement.
According to the study, the vertebrate featured three types of pigment cells in various combinations. Its skin contained melanophores, xanthophores, and iridophores, which means, the snake was a mottled green and black, with a pale underside.
How did they do it?
McNamara’s team discovered the mineralized skin cells by examining the fossil with a high-powered scanning electron microscope. Then, the researchers mapped the location and shape of each pigment cell on the snakeskin fossil and compare then with the pigment shapes in modern snakes.
Depending on the specific shape of the pigment cell, they were able to determinate certain colors, including yellows, greens, blacks, brown, and even iridescence.
Even though the pigments are now decayed, the cell shapes are so specific to each type of pigment that scientists were able to determinate the former colors.