The orchid mantis, which resembles a flower, takes on this
appearance in order to lure in prey, researchers say.
In fact, orchid mantises are even better at drawing in insects than
some actual blossoms; they not only look like flowers, but they
also beat the petally beauties at their own game, scientists
added.
Nature presents many examples of organisms evolving to mimic other
creatures. For instance, many butterfly species imitate the toxic
monarch butterfly, presumably to deter predators from eating
them.
A variety of animals impersonate plants, such as the stick insect,
which resembles a twig. Several animals color themselves like
flowers, such as flower crab spiders and ambush bugs, to camouflage
themselves when attacking insects that approach the
blossoms.
However, the orchid mantis has a full flowery disguise, complete
with legs shaped like petals, that is convincing enough for
scientists to suggest this hunter not only uses the masquerade to
hide from prey, but also to attract victims. Examples of such
aggressive mimicry have been seen before in the wild; for instance,
one species of bolas spider is known to attract male moths by
imitating female moth sex pheromones.
Scientists have championed the idea of the orchid mantis as an
aggressive mimic since the 1800s; notably, it was first suggested
by naturalist Alfred Russel Wallace, who, independent of Darwin,
also conceived the theory of evolution through natural
selection. However, this notion had never been confirmed, due in
large part to how elusive the orchid mantis is, given how extremely
rare it is even within its native habitat, the rainforests of
Southeast Asia.
"The idea that the orchid mantis mimics a flower first came about
over a century ago, but it was only ever just an idea — nobody had
done the experiments to test whether it actually occurred," said
study lead author James O'Hanlon, an evolutionary biologist at
Macquarie University in Sydney, Australia. "Now, over a century
later, we have textbooks and scientific articles stating that
mantises mimic flowers as if it was an established fact. I felt it
was my job to set the record straight and actually see whether this
phenomenon was possible."
To test the idea, scientists ventured to Malaysia.
"The hardest part about this kind of research is that you are
conducting research on an animal that nobody has ever researched
before," O'Hanlon said. "We knew almost nothing about them and had
to start from complete scratch."
The researchers first confirmed that the color of the orchid mantis
was indistinguishable from 13 species of wild flowers in the areas
the predator lived. Researchers tested the colors under the
wavelengths of light visible to the flying, pollinating insects
most likely to visit the blossoms, such as bees
and butterlies.
The scientists also watched how wild pollinators behaved around
live orchid mantises in the forest. Researchers saw more than a
dozen instances of flying insects getting close enough to orchid
mantises for the hunters to snatch the unsuspecting prey out of the
air.
"We now know that not only is it possible for mantises to lure
pollinators, but we know that they are amazingly good at it,"
O'Hanlon told LiveScience. "They can attract even more pollinators
than some flowers.
"This is the only animal in the world that we know of that
resembles a flower blossom to attract prey," O'Hanlon added. "There
are other animals that are known to camouflage amongst flowers and
ambush prey items, but they do not actually attract the
polinators themselves — the flowers they sit on are the
attractive stimulus. The orchid mantis is unique in that the mantis
itself is the attractive stimulus. This means the mantis can sit
away from flowers, perhaps on leaves or bark, and still lure in
pollinators."
Future research could analyze how predators view orchid mantises.
"It is entirely possible that orchid mantises may avoid getting
eaten if predators such as birds and lizards misclassify orchid
mantises as a flower, rather than a food source," O'Hanlon
said.
O'Hanlon and his colleagues Gregory Holwell and Marie Herberstein
will detail their findings in January in the journal American
Naturalist.
An adult female orchid mantis ( Hymenopus coronatus) on a leaf in
the forest
An orchid mantis chomps down on a butterfly it just lured in with
its flowery disguise
