Butterflies  

To most people, insects can be very irritating and are rarely looked at as beautiful.  There is a rare occasion that some insects can be looked at a beautiful and that rare insect is the butterfly.  Butterflies are one of the most interesting insects because of their life cycle and how the evolve over time.  It is never clear what butterflies will look like when first born but when they fly around, they are an eye catching site.  They are beautiful to look at and admired by many children.  The prototypical scene of a kid chasing butterflies in the park is a very influential, story book scene.  There are many aspects of butterflies that make them so loved and adored by many people.   

It is a common belief that butterflies have very short life spans but that is not always the case.  Certain species of butterflies that reach their adult stages can live anywhere from a week to a year.  While some eggs hatch fast and have longer larval stages, others have longer stages as eggs which allow them to survive in the winter months.  Other factors that determine the length of life for butterflies is the region in which they live.  The warmer the region, the longer the butterfly can live after hatching.   

 One of the most interesting aspects of butterflies is their life cycle and how they come to be a butterfly.  When starting as an egg, they are made with a rough exterior shell that protects them from harm.  The hard and rigid outer shell of a butterfly egg is called chorion and is lined with wax that prevents the egg from drying up before hitting it larva stage.  Each egg contains a funnel shaped opening that allows sperm to enter the egg and fertilize it.  Most eggs are attached to leaves by glue that hardens at a fast rate and can help form the shape of the egg.  While not much is known about this glue that holds the eggs to the leaves, it has been proven that this glue is significantly strong.  Eggs that are produced in the spring are usually hatched in the summer and this gives the butterfly a shorter life than most.  These eggs are more common in the northern states than in the southern.  They typically contain the eggs that survive over summer then born in the spring. 

When these eggs are hatched, they reach the larva stage of the life cycle.  This larva stage is where we get caterpillars from.  They survive and continue to grow by eating various plants. Certain species of butterflies produce larva that eat other insects and that is how they grow in size until they are ready to evolve.  The most common insect in which these species of butterflies eat are ants because of their small size.   

The stages in which caterpillars evolve in to butterflies are called instars.  When each instars stage is coming to an end, the larva undergoes apolysis which the outer layer is make tougher by releasing proteins from the soft under layer.  At the end of each instars stage, the larva’s outer shell becomes harder and its pigment begins to form a darker color or pattern.  In the last larva stage, to future butterfly begins to develop its wings.  While the wings cannot be seen on the outside of the larva, they are developing under the hardened shell.  The small wing disks are under the shell and do not begin to grow until the final instars stage.  During the final stage, the wings begin to grow dramatically in size.  This is also when the wings begin to form their patterns that make them different from other butterflies.   

When the larva is fully grown, they begin to look for a pupation site where they can nest and begin their transformation into a butterfly.  Larva tends to find a place under a leaf of other plant to wrap themselves in.  This is the stage where the larva goes in to a cocoon where it does not move except abdominally but the cocoon itself does not move.  The larva on the inside is still able make noised to scare off predators until they become butterflies.   This metamorphosis that larva go through to become butterflies begins with the wings feeding off nutrients and growing significantly in size.  The larva continues to transform and the entire inside of the cocoon becomes completely compressed until it is ready to break free.  Once the larva is fully transformed in to a butterfly, is breaks out of the cocoon and is released into the world.   

Most people do not know that butterflies actually have four wings that are covered in scales. The scales are where the butterflies get their color and pattern which makes them distinct from all others.  The coloration of the scales comes from the light that hits it as well as the pigment of the original larva.  All butterflies have a forewing and a hind wing on both the left and right side of the body.  The hind wings of butterflies allow them to make swift and right turns when flying so that they can evade predators.  The body of butterflies consists of a head, thorax, and abdomen.  They also have two antennae and two eyes.  Butterflies usually feed off nectar from flowers but find other places to get their nourishment from.  Such things as pollen, tree sap, decaying flesh, and rotting fruit are where butterflies look to get their nourishment.  In their adult stages, butterflies can on consume liquid and use their antennae to pick up scents of nectar in the air.   

Many butterflies migrate in the colder months and the Monarch butterfly has one of the longest migrations.  They migrate from Mexico to northern United States, southern Canada.  Other breeds of butterflies that have significantly long migration patterns are the Painted Lady and Danaine butterflies.  Overall there are between 15,000 and 20,000 species of butterflies.  Other notable breeds are the Common Yellow Swallowtail, Plum Judy, Speckled Wood, and Mallow Skipper.   

One Hundred Butterflies