Strange but true !
caterpillar on Earth ?
Caterpillars come in
some strange shapes, but there can be few creatures more
weird-looking than this bizarre Euphobetron
moth larva ( Limacodidae ) from French Guiana. The photo does not
depict a group of larvae - it is a single larva with enormous hairy
limb-like lateral extensions!
Euphobetron aquapennis larva, French
Guyana © Stéphane Brûlé
Plants that trick
of Cattle Heart butterflies ( Parides )
from South America feed on Aristolochia
vines, but some vines can defend themselves by only "permitting" the
butterflies to lay a small number of eggs. If extra eggs are laid,
the leaf around the egg dies, and the dead tissue drops to the
ground, carrying the egg with it !
A similar trick is played by
Passiflora vines, which produce
stipules at the base of leaf stems, that induce egg laying by some
species of Heliconiine butterflies. A day or two later the stipules
drop off, carrying the eggs with them. Some other
Passiflora vines produce tiny tubercles
on the stipules that mimic Heliconiine eggs. Any butterfly visiting
the plant sees the false eggs and is misled into thinking that the
plant is already overladen with eggs, so is inhibited from adding
Heliconius erato, Rio Madre de Dios,
with ears !
Some butterflies can detect sound, using "ears" on the underside of
their wings. These microscopic funnel-shaped ears are covered with a
thin membrane that vibrates in response to high frequency sound. The
ear is only present in certain butterfly families.
Some scientists believe that all early butterflies were nocturnal,
and that the ears evolved to enable them to detect and avoid
predatory bats. Other butterfly families which do not possess ears
are thought to have evolved daytime flight as an alternative
In Morpho helenor the eardrum is located
at the base of the wing.
Caterpillar cannibals !
Caterpillars of the
Scarce Swallowtail Iphiclides podalirius
are territorial. The silk trails which they lay as they walk along
twigs have a slight odour. This enables each larva to recognise it's
own silk trail, and use it as a route map to find it's way back to
particularly succulent leaves. If two larvae meet, the larger one
spins a silk web around the smaller one to kill it, or bites it to
Epiphile caterpillars in South America are equipped with long
sharp poisonous "antlers" which they use to defend themselves
against other insects. If disturbed they swish their heads
violently, using the antlers to puncture the skin of attacking
insects. The lepidopterist Muyshondt observed
Epiphile caterpillars attacking each other, locking antlers
Headless butterflies can still
In June 2010, when in the Peruvian
Andes I chanced upon a group of Diaethria
butterflies settled on the ground. Most were busily imbibing
mineralised moisture from the damp sand. One particular butterfly
however was walking about, slowly fanning its wings. I crept closer
in order to photograph it, and peering through the camera viewfinder
I suddenly realised that the butterfly had no head! Despite having
been decapitated ( following an attack by a bird or a wasp? ) it was
perfectly able to walk, fan its wings and even to fly short
The explanation is that insects
have a nervous system in which certain functions are not centralised
on the brain. Hence reproduction, locomotion and respiration are not
dependent upon retaining a head. This not only explains why a
headless Diaethria can walk and fly, it
also explains how a male praying mantis can complete a sequence of
mating processes with a female while she is eating his head ! This
incidentally is normal behaviour for mantises - males passively
submit to cannibalism, a practice that may have evolved because
copulation duration and fertilisation success are almost doubled
when the male is cannibalised.
Diaethria clymena - walking and
fanning its wings after decapitation, Shima, Peru ©
Intelligent butterflies !
seemingly complex courtship rituals of many butterflies implies that
they have some degree of intelligence, but careful analysis shows
that the rituals are merely a series of instinctive responses to
specific stimuli. A female for example might react in a certain way
if approached by a male and showered with pheromones, but the male
then also has to respond in a particular way which signals the
female to initiate the next stage in the ritual, and so on.
there is some evidence that certain butterflies do demonstrate
intelligence and reasoning.
proven that Heliconius butterflies can
learn home ranges within which they can memorise the locations of
nectar and pollen sources, host plants and communal roosting sites.
They are able to plan the most efficient route by which to visit all
nectar / pollen sources in the vicinity by using simple calculations
akin to what mathematicians call the "travelling salesman algorithm".