|Emperor Gum Moth, Opodiphthera eucalypti|
Moths are insects of the order Lepidoptera. They are closely related to butterflies, which evolved from them. Most species of moth are only active at night. They can be told apart from butterflies in several ways. Moth antenna look like little feathers, and their wings are held flat on their backs when they are not flying.
Most Lepidoptera are moths. There are thought to be about 160,000 species of moth (nearly ten times the number of species of butterfly). Thousands of species are still to be described. Most moths are tiny: they are called micromoths or microlepidoptera. The larger moths are much better known, but fewer. Most species of moth are nocturnal, but not all. There are crepuscular and diurnal species.
Moths as pests[change | change source]
Moths, specifically their caterpillars, are a major farm pest in many parts of the world. Caterpillars eat the plants that farmers grow and sometimes kill them. The caterpillar of the gypsy moth (Lymantria dispar) causes great harm to forests in the northeast United States. In warm climates, the diamondback moth (Plutella xylostella) is perhaps the most serious pest of cabbage crops.
Several different kinds of moths are commonly regarded as pests because their larvae eat fabric such as clothes and blankets made from natural fibers such as wool or silk. They are less likely to eat fabric containing artificial fibers. There are some reports that they can be repelled by the scent of wood from juniper and cedar trees, by lavender, or by other natural oils. However, many consider this unlikely to prevent moths from living somewhere. Chemicals are the most effective way to keep moths away, however, there are concerns about the chemicals being dangerous to people. Moth larvae are not killed by freezing the items they live in.
Some moths are farmed. The most important of these is the silkworm. It is farmed for the silk with which it builds its cocoon. The silk industry produces over 130 million kilograms of raw silk, worth about 250 million U.S. dollars, each year.
Attraction to light[change | change source]
Moths will fly around bright objects, and appear to be attracted to light. Most scientists think that this is because moths use the light of the moon to help them fly in a straight line. The light from lamps confuses the moths.
Pollination[change | change source]
Moths usually pollinate night-blooming flowers because they are nocturnal (they rest during the day and come out at night). A moth uses its proboscis to collect nectar just like a butterfly does. However, moths do not always land on the flower to get the nectar: they often hover near the flower and flap their wings hard while they sip the nectar. Because of this, moth-pollinated flowers do not need a landing pad. In fact, some moth-pollinated flowers point downward, like the yucca flowers.
Predators and parasites[change | change source]
Nocturnal insectivores often feed on moths. Many bats, and some species of owls and some other birds eat moths. Moths are also a minor part of the diet of some lizards, cats, dogs, rodents, and some bears. Moth larvae are eaten by many birds, and are also vulnerable to parasitism by ichneumon wasps.
Many adult moths and larvae are protected by noxious substances eaten by the caterpillars. They advertise their foul taste in various ways. Warning colouration is visible by day, and some adult moths emit clicks which bats learn are warning signals.
Baculoviruses are double-stranded DNA viruses which parasitize insects. They are often used as biological control agents. They are members of the Baculoviridae, a family that is restricted to insects.
There is evidence that ultrasound in the range emitted by bats causes flying moths to make evasive manoeuvers because bats eat moths. Ultrasonic frequencies trigger a reflex action in the noctuid moth that cause it to drop a few inches in its flight to evade attack. Tiger moths also emit clicks which foil bats' echolocation.
Notable moth species[change | change source]
Large and dramatic Moth species include:
- Death's-head Hawkmoth Acherontia sp.
- Luna Moth Actias luna
- Atlas moth Attacus atlas The largest moth in the world
- Emperor Gum Moth Opodiphthera eucalypti
- Polyphemus Moth Antheraea polyphemus
Moths that are of economic significance include:
- Gypsy moth Lymantria dispar
- Cotton bollworm or corn earworm Helicoverpa zea, a major agricultural pest
- Codling moth Cydia pomonella, a pest mostly of apple, pear and walnut trees
- Light brown apple moth Epiphyas postvittana
- The silkworm Bombyx mori is the larva of a moth.
Other notable moths:
Other pages[change | change source]
|Wikispecies has information on: Lepidoptera.|
References[change | change source]
- "Moths". Smithsonian Institution. http://www.si.edu/Encyclopedia_SI/nmnh/buginfo/moths.htm. Retrieved 2012-01-12.
- Jones, G; D A Waters (2000). "Moth hearing in response to bat echolocation calls manipulated independently in time and frequency". Proceedings of the Royal Society B Biological Sciences 267 (1453): 1627–32. doi:10.1098/rspb.2000.1188. PMC 1690724. PMID 11467425.
- NPR.org, Some moths escape bats by jamming sonar (video)