Notes

Animal Life Cycles

Animals that Grow Up (Simple Life Cycle): Most animals including fish, mammals, reptiles and birds have very simple life cycles:

~ they are born (either alive from their mother or hatched from eggs)

~ they grow up

These animals have three stages -- before birth, young and adult. The young are typically similar to the parent, just smaller. The young slowly "grow" to become adults.

Amphibians

Amphibians, like frogs and newts, have a slightly more complicated life cycle. They undergo a metamorphosis (a big change):
~ they are born (either alive from their mother or hatched from eggs)
~ they spend their childhood under water, breathing with gills
~ they grow into adults and move to the land, breathing with lungs
Animals that Undergo a Complete Metamorphosis:
Insects
These insects have four stages in their life cycle:
egg: unborn stage.
~ larva: young stage -- this is when most of the feeding is    done.(they usually look like worms)
~ pupa: inactive (no feeding) stage between larva and adult stages.(usually well camouflaged)
~ adult: final, breeding stage.(they usually grow wings)

Animals that Undergo an Incomplete Metamorphosis:
About 10% of insects go through an incomplete metamorphosis. They do not have a pupa form --
these include dragonflies, grasshoppers and cockroaches.

These insects have three stages in their life cycle:
~ egg: unborn stage.

~ larva: young stage -- this is when most of the feeding is done.
~ adult: final, breeding stage - including wings.

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