Types of Metamorphosis, Stages and Examples
What is Metamorphosis?
Metamorphosis is a biological process by which some animals change forms throughout their life cycles.
It describes how an organism undergoes a transformation from one distinct form to another during its development, such as from the tadpole to the froglet and from the froglet to the adult frog. The metamorphosis process can be observed in various animal groups, particularly insects and amphibians.
Types of Metamorphosis
Stages of Incomplete Metamorphosis
Egg: Insects that have undergone incomplete metamorphosis lay eggs, which are the first stage of life. These eggs later hatch into nymphs.
Nymph: After hatching from the egg, the insect enters the nymph stage. Nymphs look like adults but lack certain characteristics, such as wings or reproductive organs.
During this stage, the nymph sheds its skin FIVE to SIX times to grow into an adult. And this process is known as molding. With each molt. The nymph gradually resembles the adult form more closely.
To survive, nymphs start to eat succulent and soft plant foliage just after hatching from the egg. This stage of the life cycle lasts for about five to six weeks until it matures into an adult.
Adult: This is the THIRD and final stage of the life cycle of a fully developed adult insect. The adult typically possesses all the features of its species, including wings and reproductive organs.
Stages of Complete Metamorphosis
Complete metamorphosis, also known as holometabolous metamorphosis, is a more complex type of metamorphosis that involves four different stages: egg, larva, pupa,and adult. The butterfly is an example of Complete Metamorphosis.
In this process. The changes between these stages are more dramatic and involve a complete restructuring of the organism’s body.
Egg: Similar to incomplete metamorphosis, the life cycle begins with an egg.
Larva: The larva, or caterpillar, that hatches from the egg is the SECOND stage of the life cycle of the insect. The plural for larva is called LARVAE. A caterpillar’s main activity is eating. They almost never stop eating, so they can grow quickly.
The first meal for most caterpillars is the eggshell, and then they eat the leaf they were born onto.
The development of a caterpillar is called INSTAR. At this stage, the outer layer of the caterpillar, called the CUTICLE, is removed. This process of cuticle removal is also called APOLYSIS or MOLTING. In simple words, molting means shedding outgrown skin.
Before going to the third stage of life, butterflies increase their body mass by over 100 times their birth size. The caterpillar undergoes about 4 to 6 moltings. It means they shed their skin 4–5 times.
The Pupa or Chrysalis: Once larvae have completed their growth phase, they progress into the pupal stage, also known as the Chrysalis.
During this stage, the larva goes through an incredible change within a protective structure called a cocoon (in moths and butterflies) or a pupa case (in beetles). Inside the cocoon or pupa case, the larva’s body undergoes significant changes, including the development of adult structures such as wings, legs, and reproductive organs.
Adult: After the metamorphic transformation is complete, the adult insect emerges from the pupa. The adult typically has a distinct appearance and different behaviors from the larval stage. At this stage of the life cycle, the insect is capable of reproducing and continuing the life cycle.
Examples of insects that undergo complete metamorphosis include butterflies, moths, beetles, bees, flies, and ants.
Difference between Incomplete metamorphosis and Complete metamorphosis
Key Terms
- Metamorphosis: a biological process by which some animals change forms throughout their life cycles.
- Incomplete metamorphosis: also known as hemimetabolous metamorphosis, Involves three different stages: egg, nymph, and adult.
- Complete metamorphosis: also known as holometabolous metamorphosis, involves four different stages: egg, larva, pupa,and adult.
- Molting: to shed the exoskeleton, or the outgrown skin.
- Life cycle: stages an animal goes through during its life.
- Animal life cycle: shows how they grow and change over time.