Flying dragons in Borneo adopt Christmas colors to mimic the red and green hues of falling leaves in an effort to hide from predatory birds, according to new research. But the red and green colors of different Draco populations have nothing to do with a festive spirit.
“It’s a cool finding because these gliding lizards are matching the colors of falling leaves and not the leaves that are still attached to the tree,” said Danielle Klomp, a researcher at the University of Melbourne and the University of New South Wales and the lead author of the study released today in Biology Letters. “In the mangrove population the leaves on the trees are bright green, but turn red shortly before falling to the ground, and it is this red color that the lizards mimic in their gliding membranes. This allows them to mimic a moving part of the environment—falling leaves—when they are gliding.”
The gliding lizard Draco cornutus uses extendable membranes to escape from predators in the treetops by letting them glide through the forest—the only lizard genus known to fly in the world. The lizards typically only come down to the ground when the females lay eggs in the dirt.
Klomp and a team of others working on the project observed two different populations of flying dragons on the island and found that each had a distinct set of colors that matched their respective habitats.
While the coastal mangrove population matched the red color of falling leaves, a population of flying lizards in the lowland rainforest took on more of a dark brown and green color to match local leaves in that area.
“Perhaps these populations may have originally had the same gliding membrane colors. But as they have moved into different forest types their colors have adapted to closely resemble the colors of falling leaves in the different forests,” Klomp said, adding that the phenomenon was known as divergent evolution.
She said that birds can perceive the same colors humans can as well as ultraviolet light, so the colors on lizard membranes could confuse them.
The researchers spent hours filming lizard flights in an attempt to determine whether they also used these colors to communicate the same way other reptiles do but they found it was strictly used for camouflage.