Butterfly

{{Automatic taxobox
| name = Butterflies
| fossil_range = Palaeocenepresent ~60 mya {see text}
| image = Fesoj - Papilio machaon (by).jpg
| image_caption = *Papilio machaon*
| taxon = Rhopalocera
| subdivision_ranks = Subgroups
| subdivision =
* Superfamily Hedyloidea:
** Hedylidae
* Superfamily Papilionoidea:
** Hesperiidae
** Lycaenidae
** Nymphalidae
** Papilionidae
** Pieridae
** Riodinidae
}}
 (*Euschemon rafflesia*) is the most distinct skipper butterfly, forming a subfamily of the Hesperiidae]]
: the excellent leaf-mimic *Gonepteryx rhamni*, the common brimstone, on purple loosestrife]]
 inachus'' is a nymphalid butterfly found in tropical Asia. With its wings closed, it looks like a dry leaf with dark veins]]

A **butterfly** is a (usually) day-flying insect of the order Lepidoptera. They are grouped together in the suborder **Rhopalocera**. Butterflies are related to moths, from which they evolved about 56 million years ago.

The life of butterflies is closely connected to flowering plants. Their larvae (caterpillars) feed on plants, and their adults feed on flowers. They lay their eggs on the plants their caterpillars feed on. Butterflies have a long history of co-evolution with flowering plants. Many of the details of plant anatomy are related to their pollinators, and vice versa. The other notable features of butterflies are their extraordinary range of colours and patterns, and their wings. These are discussed below.

Angiosperms (flowering plants) evolved in the Lower Cretaceous, but did not become common until the Upper Cretaceous. Butterflies were the last major group of insects to appear on the planet. They evolved from moths in the latest Cretaceous or the earliest Cainozoic. The earliest known butterfly fossils date to the mid Eocene epoch, between 40 and 50 million years ago.

Like moths, butterflies have four wings covered with tiny scales. The front and back wings are usually zipped together, so that the insect looks as if it has only two wings. When a butterfly is not flying, its wings are usually folded over its back. The wings are patterned and are often brightly coloured. There are many different kinds of butterflies. The males and females of each kind are often slightly different from each other. Butterfly watching is a popular hobby. Some people also keep collections of dead butterflies that they have caught, but they find out that the colour fades.

Like all insects with complete metamorphosis, a butterfly's life goes through four distinct stages. It begins as an egg, which  hatches into a larva (a caterpillar). After some time, the larva turns into a chrysalis. While it is in the chrysalis stage, it changes to become an adult butterfly. These changes are only beginning to be understood. To complete the cycle, adults mate and the females lay eggs. 

Butterflies are any of the species belonging to the superfamilies Papilionoidea and Hedyloidea. Butterflies, along with the moths and the skippers, make up the insect order Lepidoptera. Butterflies are nearly worldwide in their distribution.

## Predators and defences 
### Predators 
The main predators of butterflies are birds, just as the main predators of the crepuscular moths are bats. Also monkeys and tree-dwelling reptiles are predators, and some insects and spiders. All reptiles have good colour vision, so that butterfly coloration is seen by them.

### Defences 
The extraordinary colours and patterns on the wings and body can only be understood in terms of their function. Some of the most obvious functions of colour are:
# Camouflage: enabling the insect to remain hidden from view
# Signalling to other animals
## Warning colouration: signalling to other animals not to attack. Caterpillars may have stored poisons from their food plants.
## Mimicry: taking advantage of another species' warning coloration
## Sexual selection: finding a mate
## Other kinds of signalling:
# Diversion
## : unexpected flashes of colour or eyespots

The details vary from group to group, and from species to species. The caterpillars also have colours with similar functions. The poisonous substances which make some butterflies  to eat are got from the plants eaten by their caterpillars.

## Body 
Like most insects, butterflies have three main body parts. These parts are the head, the thorax, and the abdomen. The body is protected by the exoskeleton. The body is made up of sections, known as segments. In between the segments there are  areas that allow the butterfly to move. All three parts of the body are covered in very small scales. The scales give the butterfly its colour.

### Wings and flight 
Butterflies have a very characteristic flying style. They usually do not fly in straight lines. Their style is well described by the children's version of their name: 'flutter-by'.  The way they fly presumably makes them harder for birds to catch. 

Some species are capable of strong, long flights (see monarch butterfly migration) and others never leave the woods they were born in. They can survive bird pecks on the wings. Late in the season damage to their wings can often be seen, though they continue flying quite well.

When they are alive, it is often difficult to see they have four wings. The wings on each side are linked by a row of little hooks. So in practice they fly as if they had one large wing on each side.

### Head 
The head is the first part of the body. It has the eyes, mouth parts, and antennae. At the end of each foot, there is a pair of claws. Butterflies in the family Nymphalidae have very short front legs. They keep there front legs close to their bodies. This makes it look like they only have two pairs of legs.

A butterfly has two pairs of wings. Each wing has hollow tubes called veins. The colors and patterns of butterflies are made by tiny scales. The scales overlap each other. They are connected to the wing. If a butterfly is , the tiny scales may rub off.

Caterpillars in the subfamily Miletinae eat insects in the order Hemiptera. This includes aphids, mealybugs, leafhoppers and treehoppers.p356

Caterpillars in the family Papilionidae have a special organ. This organ is called an osmeterium. It is a bad-smelling gland that is shaped like a snake's tongue. It is kept behind the inside of the head. When a predator tries to eat the caterpillar, the caterpillar  the osmeterium. This usually scares the predators away. Butterflies evolved from moths. The oldest known butterfly is *Protocoeliades kristenseni* from the Palaeocene of Denmark, about 55million years ago. It belongs to the family Hesperiidae (skippers). Molecular clock estimates suggest that butterflies originated sometime in the mid-Cretaceous, but only significantly diversified during the Cenozoic. Genetic data suggest they originated in North-America 102.5–100.0million years ago from a nocturnal moth ancestor that fed on legumes. Only about 17million years ago did they colonize Europe. The oldest American butterfly is from the later Eocene from the Florissant Formation fossil beds, about 34million years old.

## Butterfly families 
### Some colourful butterflies 
 
File:Yellow Jezebel ( UN ).jpg|Yellow jezebel 
File:Blue Pansy I IMG 6486.jpg|Blue pansy 
File:Callophrys Rubi Oulu 2007 05 27.JPG|Green hairstreak 
File:Gulf Fritillary Butterfly on a Lantana 18 crop 2.jpg|Gulf fritillary 
File:DirkvdM sara longwing-crop.jpg|Sara longwing 
File:Yamfly - Arunachal Pradesh.jpg|Yamfly 
File:Nymphalis Antiopa Oulu 2007 06 10.JPG|Camberwell beauty 
File:Common Blue Bottle I IMG 8918.jpg|Common bluebottle 
File:Common Mime - Papilio clytia (dissimilis form) on Jatropha panduraefolia in Kolkata Iws IMG 0217.jpg|Common mime 
File:Pale Grass Blue I IMG 6722.jpg|Pale grass blue 
File:Common Four-ring (Ypthima huebneri) in Kolkata Iws IMG 0303.jpg|Common four-ring 
File:Tit Butterfly I2 IMG 3272.jpg|Western blue sapphire 
File:Female Black Swallowtail Megan McCarty08.jpg|Black swallowtail 
File:Diaethria eluina.jpg|*Diaethria eluina*  
File:Common Grass Yellow.jpg|Common grass yellow 
File:B cool - Malay Lacewing (by).jpg|Malay lacewing
File:Tagpfauenaugen1.jpg|*Inachis io*
File:Parnassius phoebus.jpg|*Parnassius phoebus*
File:Red Helen (Papilio helenus) at Samsing, Duars, WB W IMG 6219.jpg|*Papilio helenus*
File:Schwalbenschwanz papilio machaon.jpg |*Papilio machaon*

### Monarch butterfly gallery 
 
File:Monarch Butterfly Pink Zinnia 1800px.jpg|A monarch butterfly, with closed wings, feeding on nectar from a garden flower
File:Monarch Butterfly Danaus plexippus Laying Egg 2600px.jpg|A female butterfly laying eggs on "Swan plant".
File:Monarch Butterfly Danaus plexippus Vertical Caterpillar 2000px.jpg|The caterpillar of a monarch butterfly 
File:Monarch Butterfly Cocoon 3.jpg|The chrysalis of a monarch butterfly

## Related pages 
*Differences between butterflies and moths
*Defence against predation
*Animal colour
*Moth
*Lepidoptera

## References 
## Further reading 
* Boggs C; Watt W. & Ehrlich P. 2003. *Butterflies: evolution and ecology: taking flight*. University of Chicago Press, Chicago, USA.
* Pyle R.M. 1992. *Handbook for butterfly watchers*. Houghton Mifflin.