Page 12 - DK Children's Encyclopedia

How this book works

Ever wonder what a planet is? Do you know the difference between frogs
and toads? Every page in this encyclopedia is packed with fun facts and amazing

photographs. Dive right in or jump to a page that catches your eye to discover
all about our wonderful world. The helpful tips here will guide you through
using this book.

Alphabetical pages See also
The book’s pages are arranged If you enjoy reading a page, you can use the
alphabetically. You can look up topics “see also” box to find similar pages in the book
using the contents list, which starts and see where they are. This lets you make links
on page four, or flip through the across topics and subject areas and create your
pages in whichever order you like. own journey through the encyclopedia.

Amphibians SEE ALSO Follow the suggestions
▸ ▸ Eggs p.86
▸ ▸ Water pp.120–121 In the “see also” box, in the “see also” box to
Amphibians are animals that spend their lives in and ▸ ▸ Invertebrates
around water. They hatch in water from eggs. As they p.139 “p.” stands for page get to related topics
grow they develop lungs that let them breathe on land. ▸ ▸ Metamorphosis and “pp.” for pages. elsewhere in the book.
p.163
Amphibian skin must always be wet, so they stay close ▸ ▸ Reptiles p.210
to water. There are three main groups of amphibian.
▸ ▸ Skin p.229
Newts and salamanders Caecilians Metamorphosis SEE ALSO Reptiles SEE ALSO
▸ ▸ Amphibians p.15
▸ ▸ Amphibians p.15
These long-tailed amphibians can Though they look Forever young ▸ ▸ Animal groups Reptiles are scaly-skinned, cold-blooded animals. Most ▸ ▸ Antarctica p.24
p.22
replace injured body parts by growing like worms, caecilians Axolotls are unusual, Some animals go through amazing changes between birth ▸ ▸ Eggs p.86 reptiles lay soft, leathery eggs. A baby reptile grows inside ▸ ▸ Deserts p.78
and adulthood. Their appearance changes so much that
new ones. An eye, leg, or tail takes (se-sill-yens) are amphibians. because they stay in water their fully grown shape is completely different to the ▸ ▸ Insects p.134 the egg and then, when it’s ready, breaks its way out. ▸ ▸ Dinosaurs p.80
just weeks to replace. They live underwater or in all their lives. They keep newborn one. This process is called metamorphosis. ▸ ▸ Life cycle p.146 There are four main groups of reptile. ▸ ▸ Eggs p.86
▸ ▸ Evolution p.95
underground burrows on land. their tadpole-like fins and ▸ ▸ Sun p.247
feathery gills even as
an adult.
Bright yellow markings
warn attackers that the fire Birth of a butterfly 2. Caterpillar All reptiles have Some lizards
scaly skin.
A hungry caterpillar
salamander is poisonous. Becoming a beautiful butterfly is a emerges from the egg. can move their
long process involving many stages It eats leaves and begins eyes to look in
and different forms. The process to grow. Although it two directions
at once.
Congo caecilian takes between a month and a year. starts life small, the
caterpillar develops
quickly. Metamorphosis
is a Greek word
meaning
Fire salamander “change in
shape.”
Large, bulging 1. Eggs Lizards
Butterflies start out as tiny
eyes help toads Axolotl eggs, laid on plants. The These reptiles have many skills.
and frogs to see size, shape, and color of the 3. Chrysalis This chameleon can change the
The caterpillar wraps
egg depends on the type of
in all directions. butterfly. itself in a protective layer color of its skin. Other reptiles can
called a chrysalis. Inside, run up walls, or break off their tails
the caterpillar completely
Frogs and toads Amphibians can The chrysalis is changes its body shape. to escape danger.
attached to a
The most common group breathe through branch or leaf. Tortoises have
their skin.
of amphibians includes 4. Butterfly hard shells.
frogs and toads. Frogs are Once the changes are Crocodiles
complete, a butterfly
usually wetter, smaller, and Frogspawn emerges from the and alligators Crocodiles and
chrysalis. In a few hours,
alligators have
smoother than toads. the butterfly can fly, and Tortoises These giant reptiles have strong jaws.
the life cycle begins again.
existed since before dinosaurs.
Tadpole and turtles Reptiles live on They hide under water, then
Adult frog Turtles live in water every continent spring up to catch their prey Basking
and tortoises live on
and drag it under.
Reptiles are cold-blooded
Toads have dry, bumpy the land. Their shells except Antarctica. animals. They get the heat
protect them, but are
their bodies need from the
skin, unlike frogs that The chrysalis heavy, so they move world around them, lying in
is left empty.
the sunshine to warm up.
have wet, smooth skin. Green tree frog Froglet very slowly out They hide in the shade to keep
of the water.
themselves from overheating.
Becoming a frog
The life cycle of a frog has many stages. A female Snakes
lays many eggs, called frogspawn, usually in The wings need to All snakes swallow their prey
water. These hatch into tiny tadpoles with gills for dry out before the whole. They smell using their
breathing. Tadpoles grow bigger and develop legs. butterfly can fly. tongues. Some snakes have
Over a few more weeks, a froglet loses its tail,
Webbed feet on the grows a frog’s tongue, and becomes an adult. poisonous bites, but most
are not dangerous to people.
back legs help frogs
and toads to swim 163 210
in water.
The color at the top and bottom of
the page shows which type of subject
Oriental fire-bellied toad
15 the page is about. This turquoise color
shows that the amphibians page is
about nature (see below).
Subject areas
The encyclopedia covers
nine different subject areas.
Each one has its own color,
which is shown at the top Art People History Earth Nature Science Technology Space Human
and bottom of the page. body
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