Amazing creatures #5, Butterflies. (Why is blue so rare?)

Butterflies belong to the largest group of animals, that is, to the one that has a greater number of species: insects. Its group (the lepidoptera) occupies the fourth place in terms of number and diversity of species, after the beetles, hymenoptera and diptera.

What are butterflies? You must know that they are insects, and as such, they are also arthropods, butterflies have the basic characteristics of this group. They have the body divided into three clearly differentiated parts: head, thorax and abdomen.

In the head are the mouth, antennae, palps and eyes. The thorax, divided into three segments, has three pairs of articulated legs (one pair attached to each thoracic segment) and two pairs of wings (in the second and third segments). The abdomen is the most segmented part of the body; It consists of ten segments, although only eight are clearly visible.

A characteristic feature of butterflies are the scales, which cover the entire body of adults, especially the wings; the name Lepidoptera means "wings with scales". In addition to the scales, they present numerous hairs in different parts of the body and, sometimes, also in the wings.

The colored scales, superimposed on one another like the roof tiles, form the wonderful and elaborate drawings of the wings; colors are produced chemically by pigments and physically by diffraction and refraction of light.

For most people, the word butterfly evokes the image of the adult or imago. In general, we do not think about the complex development that precedes the appearance of the creature with its beautiful shape and colorful wings.

Butterflies, like the rest of insects, undergo a process known as metamorphosis, in which they follow in succession several completely different growth phases, starting with the egg and ending with the adult.

The lepidoptera undergo a complete metamorphosis, passing through four main phases, alternating always an active phase with an inactive or immobile phase. The four phases are:

-Egg

-Larva or caterpillar

-Pupa or chrysalis

-Adult

As to how the butterflies reproduce, the adult imago or butterfly is an eminently reproductive phase, its objective is reproduction and its entire life is focused towards this end.

The male seeks a virgin female, copulates and fertilizes it, and the female lays eggs. This ends the butterfly's life cycle and then dies. The egg marks the beginning of a new cycle.

It is estimated that there are approximately 200,000 species of butterflies and moths on earth, although to date only around 130,000 have been described. The rest is not yet known, if it is ever discovered, since today the animals, and this includes the butterfly, are decreasing in numbers at such a rate that many species can disappear before they are discovered.

Adult butterflies are able to feed on the nectar of flowers, which is the source of sustenance for most of these species. The plants benefit from this association because, while they feed, the insects transfer pollen from one to another, thus ensuring its reproduction, it is the zoocoria.

The butterflies are nourished thanks to its trunk, a long, hollow tube that winds up in a spiral (for this reason it is called espromrompa), whose length is closely related to the shape of the nutritious flower. When the animal does not use it, it remains coiled under the head, but when it extends it can probe with it the depths of a flower in search of nectar.

Butterflies have always been considered fragile, because they have no weapons of attack to protect themselves, apart from their great beauty and colors.

The most common tactic in butterflies is camouflage and in this way they can be confused with an ever more hostile environment.

Night moths avoid predators like birds flying at night, but sometimes they do not get rid of bats: however, many of them are able to hear their screams and thus avoid them.

Blue Morpho butterflies undoubtedly belong to the royalty of the Lepidoptera. Its large size and intense blue iridescent color, make it worthy of a position among the most beautiful and unique butterflies on the planet. This showiness has also caught the attention of collectors and jewelry manufacturers, which has put them in a serious situation of danger.

The Blue Morpho butterfly belongs to the Nymphalidae family and within this to the Morpho genus, which comprises more than 80 species of Lepidoptera.

As the name Morpho (means changed or modified) indicates, these butterflies are perceived in a different color than they really are. Its coloration is not pigmentary as it happens in the case of other species, but of structural type, which means that the bright blue color is the result of the arrangement of the scales and the reflection of the light on them. This modification of the optical properties is what causes the blue color to be perceived in an intense and bright way. Male butterflies are usually more colorful than females, since they are the ones that perform the courtship.

Blue Morpho butterflies are of great wingspan, considered among the largest species of butterflies in the world. They can reach a size that varies between 12.5 and 20 cm, depending on the habitat conditions.

They are butterflies of solitary habits, so it is not common to see a massive concentration of them, except when the mating season arrives.