Page 95 - One Million Things: Animal Life - The Incredible Visual Guide

1. Nymph lives
and hunts 2. Adult emerges.
1. Butterfly egg is
laid on a leaf. underwater.

2. Front and back blood and expand. 4. Adult flies
3. Wings fill with
1. Tadpoles breathe legs appear. 2. Caterpillar uses biting in search of
through gills. 4. Adult frog has mouthparts to eat plants. insect prey.

3. Body begins to look compact body shape.
froglike and tail shrinks.

DRAGONFLY
Some insects go through incomplete metamorphosis,
3. Caterpillar turns into
a pupa and remains
with only three stages—egg, nymph, and adult. Dragonfly
immobile for days
eggs hatch into wingless versions of adults called nymphs.
or weeks.
As the nymph grows it molts (sheds and regrows its outer
covering, or cuticle). Then the cuticle splits open and
FROG
a winged adult emerges.
Amphibians, such as frogs, undergo
metamorphosis between tadpole and adult
stage. Tadpoles hatch from eggs laid in ponds.
They feed on plants and breathe using gills. After
a while the tadpole’s back legs, and later its front
legs, emerge. Its head and eyes become more
distinct, it starts breathing air through lungs, and
feeds on small animals. Finally, its tail shrinks and, 4. Adult
butterfly
fully frog-shaped, it leaves the water.
emerges.
1. Egg laid
in bed of 2. Hatchling
stream. emerges
from egg.

PHOTOS

DELIVERED
HERE BUTTERFLY
Most insects, including
butterflies, show complete
3. Young salmon
metamorphosis. This means that 4. Mature
migrates to sea.
they pass through four distinct salmon in
life stages. A female butterfly breeding
colors.
lays eggs that hatch into larvae
called caterpillars. Each
caterpillar feeds continuously on SALMON
plants, then stops moving and Salmon spawn (lay eggs) in freshwater streams and rivers.
forms a tough outer coat to After the eggs hatch, the young fish feed and grow in their
become a pupa. Inside the pupa, native waters for months or years before migrating to the
body tissues are reorganized to sea. Here they remain for several years as they mature.
make a butterfly, which emerges They then stop feeding, change color, and swim back up
when the pupa splits open. their home river to spawn before, exhausted, they die.

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