Butterflies and Moths

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Imagine you see something fluttering around you one day. It could be a moth or a butterfly but you just don't know how to tell them apart.

Well, according to entomologists (people who study insects), the defining difference, without any exception, is in its antennae. It is found that ALL butterflies have clubbed antennae, which look like a flexible rod with a ball at the end (like a golf club). Moths have many forms of antennae, but never the clubbed form.

If you can't observe the antennae, here are some obvious differences, but there are exceptions to them:

- Moths fly out at night and butterflies come out during the day. However, some moth species are active during the day and there are also nocturnal species of butterflies.

- Moths typically fold their wings horizontally when resting, giving it a triangular tent shape and butterflies hold them vertically over the back, like opening and closing of a book.

- Moths tend to be plump and fuzzy whereas butterflies have smooth and slender bodies.

- This is a very generalised fact: moths have dull-colored wings and butterflies have bright-colored wings.

- Most moths have bristles hooking the fore-wings and hind-wings together but butterflies do not.

- Butterflies have a floating look when flying while moths fly a haphazardly random path. This is subjective though.

If you breed them, the chief difference is during the transition from a caterpillar: most moths pupa have cocoons, protective coils made from silk and leaves spun round and around the pupating caterpillar. The caterpillars of butterflies do not make a cocoon, they are naked pupa, also known as chrysalis, only wrapped by its hard shell.

Other interesting facts:

- Moths have existed about 100 million years longer than butterflies and the number of species is (about 10x) much more than butterflies. More species are being uncovered.

- Butterflies and Moths belong to the families of the second largest insect order, Lepidoptera, next to the beetles. The Latin name refers to the scale-covered, membranous wings common to all species. Most adult Lepidoptera are additionally characterized by a pair of well-developed compound eyes; mouthparts consisting of a long, coiled sucking tube, or proboscis; and prominent antennae.

- The largest moths (Attacus of Asia) can exceed 30 cm in wingspan; the wings of the smallest ones (Microlepi-doptera) span only a few mm. The largest butterflies (bird wings of Melanesia) can have wingspans of up to 25 cm; the smallest ones (pygmy blues) seldom exceed 1 cm.

- Moths' attraction to a illumination source at night is a reflex action caused by the reduction of wing motion on the side struck by the light, causing them to turn in the direction of the light.

- Moth species are considered to be among one of the most destructive pests of crops and stored products, on the other hand, almost no butterfly species attack economically important plants.

More about this author: Barnaby Meins

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