The Life Cycle of Monarch Butterflies and the Annual Migration

An amazing life cycle of monarch butterflies shows the beauty and the perfection of nature. Some insects have a complete metamorphosis which is a changing in the insect body form through different stages. Monarch butterfly undergoes a perfect complete metamorphosis process: egg, larva, pupa and adult (Bernstein, 1990). The process of metamorphosis is guided by genes. There are three hormones produced from the genes. First, Brain hormone which makes a gland in the thorax gives the second hormone (Molting hormone) which is completely depends on the third hormone (Juvenile hormone) which causes the molting of the larva when it presents in high amount. Each stage of the metamorphosis is specialized to do a particular activity so the metamorphosis process is very beneficial in that manner because it prevents a mixing between two functions that ask for huge energy such as in the caterpillar stage the mission is growing while in the butterfly stage responsible for the reproducting (Towle, 1991).
After mating, the male lepidopteran dies while the female has to survive until she lays her eggs. She chooses the place to put her eggs carefully by choosing a close spot to leaves so that the caterpillars can eat when they hatch .The mission of the caterpillar is eating. Starting with it shell which protected it as it developed .When the caterpillar grows, its ready to move to the next stage (pupa) by spinning a silk pad and hanging their heads downward from the pad . there are active changes inside the pupa to form an adult butterfly by completing the transformation of the organs and the arrangement of the muscular system then after a while its ready to emerge (Patent, 1979).

Monarch butterflies migration
Migration of monarch butterflies is the most amazing biological event on the earth. The journey of monarch butterflies is around 3100 miles (500 km). When the temperature drops in winter in the north of the U.S., butterflies migrate to the south (Mexico and California)

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