By mimicking the red and green colors of
falling leaves, Bornean lizards avoid falling prey to birds whilst gliding, new
research has found. The work suggests that populations of the gliding lizard, Draco
cornutus, have evolved extendable gliding membranes, like wings, which
closely match the colors of falling leaves to disguise themselves as they glide
between trees in the rainforest.
South-East Asia, Draco is the only living genus of lizard with extendable
gliding membranes -- call patagia -- which allow them to glide between trees in
Published Dec. 24 in
the international journal Biology Letters, the study was conducted
by PhD student Ms Danielle Klomp, based at both the University of Melbourne and
the University of New South Wales with supervisors Dr Terry Ord and Dr Devi
Stuart-Fox and collaborator Dr Indraneil Das from the University of Malaysia.
The team travelled to
Borneo and observed two populations of a gliding lizard that have different colored
gliding membranes and occupy very different habitats.
One population has red
gliding membranes, which match the color of the red falling leaves of their
coastal mangrove forest habitat. The other population has dark brown and green
gliding membranes, which match the colors of falling leaves in their lowland
They determined how
the colors would be perceived by a predatory bird and found that the gliding
membrane color would be indistinguishable from a falling leaf in the same
Birds can see
ultraviolet light as well as the colors that humans see, so it is important to
take into account how closely the colors would actually match to a bird, Ms
"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. 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." Ms Klomp said.
Because some animals
have developed color not only for camouflage, but also as a form of
communication, we also wanted to watch the lizards interact in the wild and
determine whether their gliding membranes were used for communication as well
as gliding said Ms Klomp.
The team filmed hours
of gliding lizard behavior to observe how often the colors were displayed to
"We found that
both the red and green/brown gliding membranes seem to have evolved to
specifically resemble the falling leaves in each population's particular
habitat, and are rarely used for communication," Ms Klomp said.
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, known
as divergent evolution."
Klomp DA, Stuart-Fox D, Das I, Ord TJ. 2014. Marked colour divergence in the gliding
membranes of a tropical lizard mirrors population differences in the colour of
falling leaves. Biology
Letters, 10 (12): 20140776 DOI:10.1098/rsbl.2014.0776