Lepidopteran on a flower.

A moth is an insect closely related to the butterfly. Both are of the order Lepidoptera. People who study or collect these insects are called lepidopterists. Most species of moths are nocturnal, but there are crepuscular and day-flying species. They can be distinguished from butterflies in several ways.

Some moths are leaf miners.

Attraction to light

A moth attracted by porchlight

Moths are notable for apparently being attracted to light, or more specifically, are known to circle ambient objects. The reason for this behaviour is not known. Moths do not fly directly away from the light due to a visual distortion called a Mach band. One researcher, Henry Hsiao, has conjectured that moths, as nocturnal creatures, fly towards the darkest part of the sky in pursuit of safety. Moths are thus inclined to circle ambient objects in the Mach band region, usually at a radius of about one foot, depending on the species.

Night blooming flowers usually depend on moths (or bats) for pollination, and artificial lighting can draw moths away from the flowers, impacting the plant's ability to reproduce. Light pollution is coming under increasing scrutiny as a source of many subtle ecological changes.

Moths of the type understood to be "attracted to light" are, instead, flummoxed by the proliferation of artificial lights in their local environment, which, if brighter than the brightest celestial object (e.g., the moon), will usurp that object's significance as the reference point for the moth's flight. To travel in a straight line, a moth would maintain the same angular relationship with the (relatively stationary) moon. Encountering a brighter artificial light, as the moth maintains its angular relationship to the source of light (per its evolved mode of navigating), but, because the light is nearby, that consistent angle results in a decreasing spiral, until the moth strikes the light source.

Moths as pests

A moth caterpillar eating a leaf

Moths are commonly regarded as pests because the larvae of a few species eat fabric such as clothes and blankets made from natural fibres such as wool. They are less likely to eat mixed materials containing artificial fibres.

There are some reports that can be repelled by the scent of wood from juniper and cedar, by lavender or by other natural oils. However, many consider this unlikely to prevent infestation. Naphthalene (the chemical used in mothballs) is considered more effective, but there are concerns over its effects on health. Freezing items infested with moth larvae will not kill them. An effective way of disposing of moths without the use of chemicals is to use Electric Fly Traps (http://www.fly-kill.co.uk/pages/fly_traps_focus_series.html)

Moths are sturdy and usually require a bigger force to kill them than mosquitos or flies.

Others may have caterpillars which are agricultural pests, such as the Codling Moth.

Moth species

Emperor Gum Moth

A moth

Moth species include:

• Emperor Gum Moth Opodiphthera eucalypti
• Atlas moth Attacus atlas
• Cotton bollworm or corn earworm a major agricultural pest
• Death's Head moth Acherontia sp.
• Gypsy moth Lymantria dispar
• Luna Moth Actias luna
• Peppered moth Biston betularia
• Pasture Day Moth
• Bogong Moth Agrotis infusa
• Ghost Moth Hepialus humuli
• Common Swift Hepialus lupulinus
• Six-spot Burnet Zygaena filipendulae
• Emperor Moth Pavonia pavonia
• Oak Hook-tip Drepana binaria
• Peach Blossom Thyatira batis
• Buff Arches Habrosyne pyritoides
• Figure of Eighty Tethea ocularis
• Large Emerald Geometra papilionaria
• Blotched Emerald Comibaena bajularia
• Common Emerald Hemithea aestivaria
• Blood-vein Timandra griseata
• The silkworm Bombyx mori is the larva of a moth.

External links

• Life cycle photos of the salt marsh moth Estigmene acrea (http://www.pollinator.com/plant_pol/caterpillars/barbarea_verna2.htm)
• UK Moths (http://www.ukmoths.force9.co.uk/)
• Butterflies and Moths of the Netherlands (http://www.leps.nl/)