Why is molting necessary for the growth of a butterfly?
Molting is necessary for the butterfly larvae, called a caterpillar, as it repeatedly outgrows its skin. Their skin doesn't grow to accommodate them, and therefore needs to be periodically shed to reveal new skin underneath. After about four sheds, the caterpillar will turn into a pupa and then emerge as an adult butterfly.
Arthropods are more vulnerable to predators immediately after moulting because their new cuticle is soft; this process is necessary in order to undergo the actual shedding (ecdysis) itself and essential for growth since the exoskeleton is of sufficient hardness to make growth within it impractical. Right after shedding, the arthropod will usually expand in size (often owing to water intake) and hide for a while to mitigate the risk, until the new skeleton hardens.
When arthropods outgrow their exoskeletons, they undergo periods of molting. During molting, an arthropod sheds its entire exoskeleton and manufactures a larger one to take the smaller ones place. Molting is controlled by the arthropods endocrine system. An animals endocrine system regulates body processes by means of chemicals called hormones. As the time of molting approaches skin glanes digest the old part of the exoskeleton and other glands secrete a new skeleton. Whenthe new skeleton…