Monarch butterflies are easily natures most beautiful creatures. The most common variety, and well known type of butterfly in North America is the Monarch butterfly. Scientists believe that Monarch butterflies are the only family of insects that actually migrate. As winter approaches in colder climates, the Monarch starts to slow down and reproduction stops. Over the summer, they store fat reserves in their stomach in preparation for the winter.
As temperatures drop, Monarchs begin to journey south for the winter. In the west they tend to travel south of the Rocky Mountains. Throughout the U.S., they travel to Florida, Texas and Mexico. Canadian and Northwest American Monarch butterflies travel south to the coast of California and down to Southern California. The migration distance is truly amazing considering these are such small insects. Unbelievably, once the weather warms up again, the Monarch will return north to the exact same locations where they originally migrated from. While migrating, Monarchs are known to travel as fast as 30 miles per hour. Somehow, those little wings work miracles.
Butterfly is an insect which is of interest to many people owing to its colours and beauty, habitat, and life cycle. The life cycle of a butterfly is the most explained one to kid in science classes and fairs. This can be demonstrated easily without any much set up and understood easily also. The life cycle of butterflies are described as the complete life cycle as it goes through all stages in the life cycle of insects and is in accordance with the theory. There are four stages in the life cycle of a butterfly. These are egg, caterpillar, pupa, and butterfly. Each stage is distinct from one other and is easily recognizable as well. This process in which the adult grows from the egg, undergoing different phases is known as metamorphosis. The eggs are tiny and rounded in shape. These are laid on the host plants which the caterpillar will feed on. The eggs remain in the state for six to seven days.
The caterpillar is the stage when the larva crawls out of the egg and start feeding on the host plant. It usually has interesting stripes and patterns and hairy things on its body. When fully grown into a caterpillar, it will have six legs and some extra prolegs. This phase witnesses the feeding and growth stage of the butterfly. The caterpillar feeds tremendously on the host plant and will eat almost the whole of the plant. Moulting is the process in which the outer skin of the larva is shed. During the caterpillar stage, it undergoes moulting several times due to it rapid growth.
Once it reaches a certain stage, the caterpillar goes into the dormant stage and becomes a pupa. The caterpillar creates a cocoon around the body and gets attached to the stem or underside of leaves using strong silk thread generated by self. The pupa will usually be colourful. Inside, while the pupa remains dormant, the tissues are broken down and it develops the structures of the insect like the wings, antenna, and body for it to fly out and survive in the nature. These do not fall off during winds or rains. The final stage is the butterfly which emerges from the pupa. It breaks open the covering and comes out fluttering its wings. Then it feeds on nectar and undergoes mating and lays eggs. The life span of an adult butterfly varies from species to species. Some live only for a month or two, while some lives for years.
Butterflies are the scaly winged insects with clubbed antennae. They belong to the Phylum, Arthropoda; Class, Insectaand Order, Lepidoptera. There are 1,50,000 species of butterflies and moths belonging to the Order Lepidoptera from which 1,78,20 are butterflies. There are 1501 identified species of butterflies found in India. Order Lepidoptera (Gr. lepis, scale; pteron, wing) have been classified in to two sub-Orders: Rhopalocera(Gr. rhopalon, club; keras, horn) including butterflies and Heterocera(Gr. heteros, other; keras, horn) including moths. Rhopalocera is further divided in to five families: 1. Hasperiidae, 2. Papilionidae, 3. Pieridae, 4. Lycaenidae and 5. Nymphalidae. Life cycle of butterflies include four stages (egg, larva or caterpillar, pupa or chrysalis, imago or adult) with a complete and complex metamorphosis. Butterflies are dioecious. Fertilization is internal. Eggs are laid on the upper surface of the host plant leaf immediately or after 1-2 days of fertilization. Egg is covered by a thin pellicle which is variedly sculptured and has a rosette of cells on its extreme summit.
This cell rosettehas a microscopic pore called Micropyle in its centre used for fertilization by sperm and also for respiration of the developing embryo. Larva or caterpillar hatches out after about 3 or 4 days depending on the surrounding temperature. Caterpillar is 14 segmented. Head is scleritized and is immediately followed by three thoracic segments each having a pair of true leg ending in a horny claw. From the 10 abdominal segments, prolegs are present from third to sixth abdominal segment and in the last abdominal segment. Spiracles, the breathing pores are present on the plural region through which air enters certain tubes ramifying within for the aeration of the blood. It is present in 1st thoracic, then 1st abdominal to 8th abdominal segment. The skin of the caterpillar split at the middle of the back and the larva crawl out of it. This is called moulting. The stage between the moulting is called as Instar. There are five Instars in most of the species. Last Instar is called as Prepupa. Pupa is the stage of resting and differentiation, resulting in all the organs outlined.
However its wings are small and applied close to the thorax on the lower side and the proboscis is straightened to lie between the wing case. Just before emergence, the pupal case splits open on the back. The butterfly crawls out of the chrysalis and find a suitable perch. Initially the wings are wrinkled and shriveled but slowly blood is pumped in to the veins. At this time the butterfly is very vulnerable to attacks from predators. Then the butterfly becomes ready to fly in search of food and mate. Adult butterfly can only feed the liquid food by its sucking type of mouth part.