Metamorphosis in Butterflies
Many of nature’s creatures undergo “metamorphosis” as they mature from birth to the adult stage. Metamorphosis is the abrupt alteration in the anatomy and physiology of a life form. The chicken is an example of a 2-stage metamorphosis, the egg and the chicken. However the butterfly is the example most often associated with this mystical change in life form, because the butterfly is one of the few living creatures to have a 4-stage, or “complete” metamorphosis. This involves a number of rather different phenomena, but all of them are controlled by hormones.
Click below to see a 4 minute video of this incredible transformation that a butterfly undergoes.
The Metamorphosis: The Beauty & Design of Butterflies DVD is available for purchase now. Visit www.illustramedia.com for more information.
Butterflies are found all over the world and in all types of environments: hot and cold, dry and moist, at sea level and high in the mountains. Most butterfly species, however, are found in tropical areas, especially tropical rainforests.Many butterflies migrate in order to avoid adverse environmental conditions (like cold weather). Butterfly migration is not well understood. Most migrate relatively short distances (like the Painted Lady, the Red Admiral, and the Common Buckeye), but a few (like some Monarchs) migrate thousands of miles.
Dryas iulia, or Julia Longwing
ClassificationButterflies and moth belong to the order Lepidoptera. Lepidos is Greek for “scales” and ptera means “wing”. These scaled wings are different from the wings of any other insects. Lepidoptera is a very large group; there are more types of butterflies and moths than there are of any other type of insects except beetles. It is estimated that there are about 150,000 different species of butterflies and moths (there may be many more). There are about 28,000 butterfly species worldwide, the rest are moths.
Butterfly FossilsButterfly fossils are rare. The earliest butterfly fossils are from the early Cretaceous period, about 130 million years ago. Their development is closely linked to the evolution of flowering plants (angiosperms) since both adult butterflies and caterpillars feed on flowering plants, and the adults are important pollinators.
Siproeta stelenes, or Malachite
Butterflies in Costa RicaAs mentioned, Lepidoptera is the Order of Insects that include butterflies and moths, and these are the only insects of the millions of types that have scales on their wings. It is these tiny scales that give them the beautiful mosaics of colors that they use for defense and for finding their mate.
And clearly butterflies are some of the most extraordinarily colorful animals on the planet and Costa Rica has around 1250 species, that’s more than 10% of the world’s total. However, about 95% of all the lepidoptera are moths, so obviously there are many more moths than butterflies not only in Costa Rica, but in the world.
Siproeta epaphus, or Rusty-tipped Page
Diet Caterpillars spend most of their time eating leaves using strong mandibles (jaws). A caterpillar’s first meal, however, is its own eggshell. A few caterpillars are meat-eaters; the larva of the carnivorous Harvester butterfly eats woolly aphids.
Butterflies and moths can only sip liquid food using a tube-like proboscis, which is a long, flexible “tongue.” This proboscis uncoils to sip food, and coils up again into a spiral when not in use. Most butterflies live on nectar from flowers. Some butterflies sip the liquid from rotting fruits and a rare few prefer rotting animal flesh or animal fluids (the Harvester butterfly pierces the bodies of woolly aphids with its sharp proboscis and drinks the body fluids).
Heliconius cydno Longwing
Sight Caterpillars can barely see at all. They have simple eyes (ocelli) which can only differentiate dark from light; they cannot form an image. Butterflies and moths (like many other adult insects) have compound eyes and simple eyes. They see very differently from us; they can see ultraviolet rays (which are invisible to us).
Danaus plexippus, or Monarch
Touch Caterpillars: A caterpillar’s “fuzz” gives it its sense of touch. Caterpillars sense touch using long hairs (called tactile setae) that grow through holes all over their hard exoskeleton. These hairs are attached to nerve cells, and relay information about the touch to the insect’s brain.
Butterflies and moths: Setae (sensory hairs) on the insect’s entire body (including the antennae) can feel the environment. They also give the insect information about the wind while it is flying.
Greta Oto, or Glasswing
Smell and Taste Caterpillars: A caterpillar’s maxillae (small mouth parts that are under the mandibles) have taste cells; these chemical detectors tell the caterpillar to eat when the food is appropriate, and not to eat when the food is not appropriate. The tiny antennae, which are near the mouth parts, sense smells.
Butterflies and moths: A butterfly’s antennae, palps, legs and many other parts of the body
Heliconius erato, or Small Postman
are studded with sense receptors that are used to smell. The sense of smell is used for finding food (usually flower nectar), and for finding mates (the female smelling the male’s pheromones).
A butterfly’s feet have sense organs that can taste the sugar in nectar, letting the butterfly know if something is good to eat or not. Some females also taste host plants (using organs on their legs) in order to find appropriate places to lay their eggs.
These receptors (called chemoreceptors) are nerve cells on the body’s surface which react to certain chemicals. We have similar receptors in our nose and on our tongue.
Papilio thoas, or King Swallowtail
Hearing Caterpillars startle at loud noises. Butterflies and moths hear sounds through their wings. For example, the Blue Morpho has tiny little physical ears at the front edge of the wing next to the body that can actually be seen by the naked eye.
Heliconius ismenius, or Floating Tiger
Butterflies and moths: Johnston’s organ is an organ at the base of a butterfly’s antennae. This organ are responsible for maintaining the butterfly’s sense of balance and orientation, especially during flight.
Heliconius charithonia, or Zebra Longwing
Body Temperature Butterflies can only fly if their body temperature is above 86 °F. Butterflies sun themselves to warm up in cool weather. As butterflies age, the color of the wings fades and the wings become ragged.
During the night moths can not use solar radiation to elevate their body temperature, they regulate their body temperature in a different way. To warm up, moths activate their flight muscles. The activation is such that antagonistic muscles work against one another, producing heat without much wing movement other than small, rapid vibrations which looks like shivering.
Owl Butterfly Wing Detail
Flying Butterflies are very good fliers. They have two pairs of large wings covered with colorful, iridescent scales in overlapping rows. Lepidoptera (butterflies and moths) are the only insects that have scaly wings. The wings are attached to the butterfly’s thorax (mid-section). Veins support the delicate wings and nourish them with blood.
The speed varies among butterfly species (the poisonous varieties are slower than non-poisonous varieties). The fastest butterflies (some skippers) can fly at about 30 mph or faster. Slow flying butterflies fly about 5 mph.