A male firefly glows above a field
on a summer’s night,
emitting a series of enticing flashes.
He hopes a nearby female will respond
with her own lightshow
and mate with him.
Sadly for this male,
it won’t turn out quite the way he plans.
A female from a different species
mimics his pulsing patterns:
by tricking the male with
her promise of partnership,
she lures him in–
and turns him into an easy meal.
He’s been deceived.
Behavioral biologists have identified
three defining hallmarks of deception
by non-human animals:
it must mislead the receiver,
the deceiver must benefit,
and it can’t simply be an accident.
In this case we know that the predatory
firefly’s signal isn’t an accident
because she flexibly
adjusts her flash pattern
to match males of different species.
Based on this definition,
where is animal deception seen in nature?
Camouflage is a good starting point–
and one of the most familiar examples
of animal trickery.
The leaf-tailed gecko and the
octopus fool viewers
by blending into the surfaces
on which they rest.
Other animals use mimicry
to protect themselves.
Harmless scarlet kingsnakes have evolved
red, yellow, and black patterns
resembling those of the venomous
eastern coral snake
to benefit from the protective warnings
these markings convey.
Even some plants use mimicry:
there are orchids that look and smell like
female wasps to attract hapless males,
who end up pollinating the plant.
Some of these animals benefit
by having fixed characteristics
that are evolutionary suited
to their environments.
But in other cases,
the deceiver seems to anticipate
the reactions of other animals
and to adjust its behavior accordingly.
Sensing a threat,
the octopus will rapidly change its colors
to match its surroundings.
Dwarf chameleons color-match their
environments more closely
when they see a bird predator
rather than a snake–
birds, after all,
have better color vision.
One of the more fascinating
examples of animal deception
comes from the fork-tailed drongo.
This bird sits atop tall trees
in the Kalahari Desert,
surveying the landscape for predators
and calling when it senses a threat.
That sends meerkats, pied babblers,
and others dashing for cover.
But the drongo will also sound
a false alarm
when those other species
have captured prey.
As the meerkats and babblers flee,
the drongo swoops down
to steal their catches.
This tactic works about half the time–
and it provides drongos
with much of their food.
There are fewer solid cases
of animals using signals to trick members
of their own species,
but that happens too.
Consider the mantis shrimp.
Like other crustaceans,
it molts as it grows,
which leaves its soft body
vulnerable to attack.
But it’s still driven to protect
its home against rivals.
So it has become a masterful bluffer.
Despite being fragile,
a newly molted shrimp is actually
more likely to threaten intruders,
spreading the large limbs it usually uses
to strike or stab its opponents.
And that works –
bluffers are more likely to keep
their homes than non-bluffers.
In its softened condition,
a mantis shrimp couldn’t
withstand a fight–
which is why we can be confident
that its behavior is a bluff.
Biologists have even noticed
that its bluffs are tactical:
newly molted mantis shrimp are more likely
to bluff against smaller rivals,
who are especially likely
to be driven away.
It would seem that instead of just
threatening reflexively,
the mantis shrimp is swiftly gauging the
situation and predicting others’ behavior,
to get the best result.
So we know that animals can deceive,
but do they do so with intent?
That’s a difficult question,
and many scientists think
we'll never be able to answer it.
We can't observe animals’
internal thoughts.
But we don’t need to know what an animal
is thinking in order to detect deception.
By watching behavior and its outcomes,
we learn that animals manipulate
predators, prey, and rivals,
and that their capacity for deception
can be surprisingly complex.