Exploring the World of Reptiles and Amphibians

Crocodiles

have to swallow their food
whole or rip it into chunks.
Crocodiles sometimes work together to
tear apart the body of their prey. One crocodile
holds on to the body, while the other spins
around underwater, ripping off chunks
of meat. Teeth fall out and are replaced
throughout their lives. They usually last
up to two years before falling out.

Saltwater crocodiles are giants of the reptile Nests and Eggs
world. Adult males can grow to 20 ft. (6 m) or Crocodiles reproduce by laying eggs on land.
more and weigh more than 2,200 lb. (1,000 kg). The eggs have hard shells, like those of birds.
Females are usually half the size of the males. Females start to reproduce when they are about
nine years old. They lay their eggs and bury
Female crocodiles can also hear the sound of them under a large mound of plants and soil.
the young calling from the nest as they are As the plant material rots, the heat keeps the
hatching. Adults are highly sensitive to the eggs warm and helps the embryos develop.
distress calls of hatchlings and young crocodiles The American crocodile is unusual because
and quickly come to help them. the females often just dig a hole in the sand
and lay their eggs at the bottom of it.

Jaws and Teeth DID YOU KNOW?
The shape of a crocodile’s snout provides a clue
about what it eats. Crocodiles with long, narrow An ancient crocodile called Deinosuchus
jaws and small, sharp teeth are fish-eaters. An grew to more than 50 ft. (15.2 m) long
example is Johnston’s crocodile. Species with and probably hunted duck-billed dinosaurs.
wider jaws, such as the saltwater crocodile, feed Nile and saltwater crocodiles are big
mainly on mammals. In some cases, they can enough to kill people and large animals.
eat mammals almost as big as themselves. But most crocodiles are secretive reptiles
that rarely threaten people.
The fearsome, spiky teeth in a crocodile’s jaws Saltwater crocodiles can stay underwater
are used to grip and pierce the flesh of prey, but for more than an hour.
they cannot be used to chew food. Crocodiles The muscles that open a crocodile’s jaws
are weak. A thick rubber band will easily
keep the jaws of a young crocodile shut.

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crocodilEs

Awesome ambush

Many large crocodiles lie in wait for their
prey, suddenly lunging toward the animal
in a surprise attack. The crocodile’s body
is well suited to this ambush attack. This
large, powerful reptile lurks just beneath
the surface of the water with only the
tops of its ears and eyes visible. In this
position, the crocodile looks more like
a floating log than a hidden predator.
For the final attack, the crocodile moves
incredibly quickly, seizing the prey in its
wide jaws and dragging it under the water.
It is important for a crocodile to overcome
its prey quickly as it cannot chase it over
land. Crocodiles also tire easily and take
a long time to recover from exercise of
any kind. They usually kill their prey by
drowning them. They then eat every part
of the animal, including the bones.

The temperature of the nest controls whether female hears these calls and digs the eggs from
the hatchlings turn out to be male or female. the nest. Females may also help their eggs to
Higher temperatures produce more males, hatch. They roll their eggs to and fro in their
while temperatures below 88 °F (31 °C) produce mouths, pressing them gently to crack the shell
more females. The nest temperature also affects open so the hatchlings can emerge. Once the
the skin coloration and patterning of the young. young crocodiles have hatched, the female often
carries them in her mouth down to the water.
Females often stay near to the nest and guard The hatchlings are vulnerable to predators at
the eggs from predators. The males often help this early stage, so the female stays nearby to
the females to protect the nest. When the eggs guard them until they have grown and can take
are ready to hatch, the young crocodiles make better care of themselves.
yelping noises from inside their eggs. The

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Darwin’s frog

These tiny frogs are named for the English
naturalist, Charles Darwin, who may have seen
them in Chile in 1835. Darwin’s frogs are famous for
the way in which males carry their tadpoles in their

mouths to protect them while they develop.

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Darwin’s frogs live along the shallow, cold streams FROGS and toads
in the beech forests of Chile and Argentina
in South America. When they feel threatened, these Fact File
amphibians leap into the water and often land
upside down. This sudden movement shows off their Darwin’s frog
distinctive black and white undersides. The frogs then Rhinoderma darwinii
keep very still and just drift in the water, acting as if Family: Rhinodermatidae
they are dead. Most predators prefer to eat living prey, Order: Anura
so they tend to leave the frogs alone. Where do they live?: Southern
Chile and neighboring parts of
Caring Fathers southern Argentina
The male Darwin’s frog calls for a female with a high- Habitat: Streams in beech forests
pitched whistle, which is similar to birdsong. After Size: HeadÂ

Dragon lizards

Dragon lizards are also called chisel-toothed lizards
because of the shape of their teeth. These lizards often
have spines, crests, or flaps on their heads and backs.

There are hundreds of different species.

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Dragon lizards have several features in common. snakes and lizards
They all have four legs and long, rounded tails.
Seen from above, the heads of these lizards often seem Fact File
to be a triangular shape. Many species have plump,
pear-shaped bodies, but a few are more slender. Most Dragon lizards
of these lizards have large eyes, good eyesight, and Family: Agamidae—430 species
colorful skin. Some species have large, pointed or spiny divided into 49 genera, including
scales, while others have smaller scales and a silky Agama (31 species of agamas);
texture to their skin. Males are usually brighter than Draco (28 species of flying lizards);
the females and young of the same species. Males may Phrynocephalus (43 species of
have elaborate crests and neck frills. Females of some toad-headed agamas)
species have less obvious decoration. Order: Squamata
Where do they live?: Africa, Asia,
Chisel Teeth Australia, and the Middle East; one
The teeth of most lizards are loosely joined to the species from southeastern Europe
sloping inside edges of their jawbones. In dragon
lizards, the teeth are firmly joined to the top edges of Equator
the jawbones. The teeth at the front of their heads are
often joined to form wider, chisel-shaped teeth. These Habitat: Varies from dense tropical
are more like the incisors (cutting teeth) of mammals forests to deserts
than the typical pointed teeth of most lizards. Size: Head–tail length 1.6–14 in.
(4–35 cm)
Dragon lizards are similar to iguanas in many ways, Coloration: Brown, gray, or black;
but the shape of their teeth is the main feature that some forest species are green
sets the two different groups apart. Dragon lizards live Diet: Varies from plants and
in Africa, Asia, Australia, and the Middle East. Many invertebrates to other lizards and
dragon lizards have similar lifestyles to the iguanas small mammals
of the Americas and Madagascar. American horned Breeding: Most species lay eggs,
lizards are similar to the Australian thorny devil. that hatch after about 6–8 weeks;
toad-headed agamas may give birth
Chinese water dragons live in the humid forests to live young
of central and southeast Asia, where they hunt Life span: Up to 15 years
insects and other small prey from the treetops. Status: Varies according to species

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Dragon lizards

Australian lay eggs, but some of the toad-headed
water dragons agamas from Central Asia may give
have a row of birth to live young.
long spikes at
the base of their The Central American basilisks look Australian Dragons
heads, forming similar to the water dragons and Scientists think that the first dragon
what is known sail-fin lizards that are found from lizards appeared in Australia around
as a nuchal crest. southeast Asia and Australia. 20 million years ago. The Australian
water dragon of the northeastern
DID YOU Lizard Lifestyle forests is a descendant of these
KNOW? Dragon lizards usually live on the ancient reptiles. Other modern
ground or in the treetops, but many groups include Diporiphora species,
Pogona species hide in burrows at night or during which live across Australia. They have
have a “beard” very hot or cold weather. A few live slender bodies and are marked with
on the throat, along rivers and jump into the water light stripes. Species from the group
which is made to escape predators. Flying lizards Ctenophorus often have camouflage
of pointed scales. take to the air for the same reason. colors. During the breeding season,
The thorny devil the males may have brightly colored
is covered with Almost all dragon lizards eat meat. heads and necks. Some of the larger
spines that Many will also eat plant material Australian bearded dragons can puff
protect it from from time to time. The thorny devil up their necks, making their pointed
predators. of Australia specializes in eating ants, scales stand out like “beards.” Species
Draco species lapping them up with its tongue. from the group Tympanocryptis are
from southeast called earless dragons because they
Asia can glide Male dragon lizards may threaten or have no ear openings on their heads.
from tree to tree fight other males of the same species
on “wings” of skin to win females for mating. Sometimes Spines, Sails, and Tails
supported by they use their large front teeth in the Many Asian water dragons live in
their ribs. battles. Most female dragon lizards humid rain forests. Many have bright
Butterfly lizards green colors, with low crests of large,
also use their ribs pointed scales. Some have prickly
to expand small, spines on the back of their necks
colored flaps of and over their eyes. The three sail-
skin, although
these are not
used to fly.

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snakes and lizards

fin lizards have high crests on Butterfly Lizards
their heads and backs. They live Seven species of butterfly lizards live
on islands in Indonesia and the in the humid forests of China and
Philippines and are some of the southeast Asia. Several species have
largest dragon lizards. red and black markings along their
flanks. These reptiles can expand
Toad-headed agamas live in the their ribs a little, which flattens their
deserts and grasslands of Central body and shows off their brightly
Asia, the Middle East, and the colored sides. These look like the
Arabian peninsula. They have wings of a butterfly, which is where
flat bodies, wide heads, and thin, these lizards get their common name.
spindly legs. One common species Scientists once thought that butterfly
is Phrynocephalus mystaceus. When lizards could glide short distances.
threatened, it hisses, opens its bright As they live on the ground, not in
red mouth, swings its tail around the treetops, but this seems unlikely.
rapidly, and jumps at its attacker.

Sri Lankan Specials

Several unusual agamids live only on the island of Sri
Lanka in the Indian Ocean. These lizards survive in
the few patches of rain forest there, especially
in the Knuckles Range in the center of the island.
They include the hump-nosed lizard (Lyriocephalus
scutatus; see right), which has a large, rounded
bump on its snout, as well as the rare pygmy agama
(Cophotis ceylanica). There are also five species of
horned agamas from the genus Ceratophora, but two
of these lizards do not have any horns. The rarest
horned agama, called Ceratophora tennentii, lives
only in one small part of Sri Lanka, much of which
is now converted into farmland. This species is in
danger of becoming extinct.

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Eastern box turtle

Eastern box turtles take their name for the way in which
they close up their shells like a box when threatened.
Some eastern box turtles live for more than 130 years.

They have even appeared on an American postage stamp.

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turtles, terrapins, tortoises

The domed upper shell, called a carapace, reveals Fact File
a lot about the lifestyle of the eastern box turtle.
It indicates that these reptiles spend much of their lives Eastern box turtle
on land. Turtles that live in the water usually have more Terrapene carolina
streamlined shells. The domed shell of these turtles Family: Emydidae
can sometimes cause problems for males when they Order: Testudines
mate with the females. If the males fall upside down,
they find it very hard to turn the right way up again. In Where do they live?: Eastern
most cases, the males use their powerful necks to flip United States to northern Mexico
themselves over. The bottom shell, or plastron, of a box
turtle has two hinges. This allows the turtle to shut its Habitat: Open areas of woodland;
shell completely, which protects it from predators and sometimes also in marshy areas
also allows it to conserve moisture.
Size: Shell length up to 8 in.
Deep Sleep (20 cm); weighs 2.1 lb. (1 kg)
In the northernmost part of its range, the eastern box
turtle enters into a deep sleep, called hibernation, Coloration: Brown with orange
during the winter months. Hibernation usually starts and yellow markings on the
in late October or November. These turtles usually chin and front legs
hibernate in the same sites each year, choosing to
burrow down into the soil or bury themselves under Diet: Vegetable matter and fruit,
vegetable debris or the muddy bottom of a pond or invertebrates, smaller vertebrates,
stream. Several eastern box turtles may share the same and carrion (dead animals)
hibernation sites. The hibernating turtles burrow
deeper as the soil temperature drops. Sometimes they Breeding: Females lay 3–8 eggs
bury themselves 24 inches beneath the surface. that hatch after 9–18 weeks
Those that survive the winter usually emerge from
hibernation in April. Mating takes place soon after. Life span: More than 130 years

The color of the shell varies between turtles. Status: Lower risk—near threatened
In most cases, it is brown or black and covered
with yellow or orange blotches, lines, or spots.

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Eastern newt

Adult eastern newts are also called red spotted
newts because of their distinctive coloration as
they mature. Adults usually live in water, while the
young orange newts, called efts, live on the land.

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Eastern newts have three main stages in their life newts and salamanders
cycle. These amphibians begin life as larvae in
the water. Over time, the larvae change into efts, which Fact File
live on the land. The efts then gradually develop into
adults and return to the water to breed. The most Eastern newt
familiar form in this cycle is the eft stage. Efts are small, Notophthalmus viridescens
orange amphibians that live among the leaf litter. They Family: Salamandridae
are usually active during the day. The bright color of Order: Caudata (Urodela)
the eft warns other animals that its skin is poisonous.
Indeed, the efts are much more poisonous than the Where do they live?: Eastern
adult eastern newts. Predators such as American toads, part of North America
garter snakes, red-tailed hawks, and raccoons will avoid
the efts at all costs. Their colorful defense does not Habitat: Lakes, ponds, reservoirs,
work so well in the dark, however, and bullfrogs and swamps, and water-filled ditches
some turtles will eat them. in forests or open farmland

Newt Courtship Size: Head–tail length 2.5–4.5 in.
Eastern newts usually have a very simple courtship. (6.3–11 cm)
A male displays in front of a female, she nudges his
tail, he drops a sperm packet, and she picks it up. More Coloration: Young are orange;
complex courtship displays involve the male grasping adults are olive green above and
the female with his back legs and rubbing her snout yellow below, with row of red and
with the sides of his head and front legs. He also curls black spots
his tail around and wafts scent past her nostrils. After
an hour or so, the male releases the female and drops Diet: Small invertebrates
his sperm packet. If all goes well, the female picks up
the packet. However, she may swim away or another Breeding: Females lay 25–350 eggs
male may replace the sperm packet with his own. that hatch after 20–35 days

The red eft is the intermediate stage between Life span: From 12 to 15 years
the larval and adult forms of the eastern newt.
The eft spends all of its time on the land. Status: Lower risk—least concern

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Edible frog

When a pool frog breeds with a marsh frog, they
produce a hybrid called the edible frog. This

cross between two different amphibian species has
large back legs, that are eaten as a delicacy in some

parts of the world, especially in France.

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Edible frogs are active during the day, even in frogs and toads
bright, warm weather. They sit near water,
often under a clump of grass or other plants that Fact File
provide cover from predators. The color of the
skin of these amphibians blends in well with their Edible frog
surroundings, providing good camouflage. If they Pelophylax esculenta
are disturbed, edible frogs jump into the water and Family: Ranidae
swim to the bottom, using their strong back legs and Order: Anura
webbed feet. They soon resurface, looking around Where do they live?: Central
for danger with eyes that bulge out from the top of and eastern Europe
their heads. Habitat: Canals, lake edges, ponds,
pools, and water-filled ditches; also
Males have a pair of white or pale-colored vocal lives in brackish (slightly salty) water
sacs on the sides of their heads. They puff these out Size: Head–body length 4.75 in.
to make their calls louder. Males produce loud calls (12 cm); weighs 20–75 lb. (9–34 kg)
to attract females during the breeding season, which Coloration: Green with a lighter
is usually in May. Female edible frogs are larger than stripe in center of back; back of
the males. Edible frog tadpoles are usually dark the thighs are often yellow
brown or greenish and are 1–3.5 inches in length. Diet: Invertebrates
Breeding: Female lays up to
Mixed-up Frogs 4,000 eggs in 3 clutches
Edible frogs are unusual because they are not a true Life span: 5–6 years
species. These amphibians are the result of a cross Status: Lower risk—least concern
between a pool frog (Pelophylax lessonae) and a marsh
frog (Pelophylax ridibunda). When these two frogs 113
breed they produce a hybrid edible frog. Most hybrids
cannot breed and produce young of their own. Edible
frogs are unusual because they can breed and produce
their own young. They can also breed with other marsh
frogs and pool frogs if there are no edible frogs around.

Edible frogs are green with black spots and stripes
over the back and legs. These amphibians live in
ponds, lakes, and streams across Europe.

Eyed lizard

The eyed lizard is a large, powerful European lizard
that will eat almost anything. The male’s blue spots
look like simple eyes, or ocelli, which is why this liz-

ard is also called the ocellated lizard.

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Despite its size, the eyed lizard is a shy, secretive snakes and lizards
reptile. When disturbed, it runs away at great
speed, crashing noisily through the undergrowth. It Fact File
does not live up to its scientific name lapida, which
means “graceful.” Eyed lizards usually hide from Eyed lizard
danger in burrows, under large rocks, or in holes in Lacerta lepida
walls or piles of rocks. If a predator such as fox, weasel, Family: Lacertidae
or large bird of prey corners one of these lizards before Order: Squamata
it can hide, it will open its mouth wide and make a Where do they live?: Spain,
loud hissing noise. As a last resort, the eyed lizard Portugal, southern France,
will jump forward and bite hard. and northwestern Italy
Habitat: Dry hillsides, olive groves,
Males and Females roadsides, scrubland, and vineyards
Male eyed lizards guard their own feeding and Size: Head–tail length 24–30 in.
breeding area. This is known as their territory. The (60–76 cm); weighs up to
male will sit on top of a large rock or log and watch for 17.6 oz. (500 g)
rival males, as well as predators. Males of a similar size Coloration: Green or brownish
and strength may fight for their territory. They circle green, with black stippling and blue
each other with their throats puffed out. Suddenly, one spots on the sides; females may not
male will dart forward to try and bite its rival while he have blue spots
is not looking. A male will mate with any females that Diet: Fruits and other plant matter,
live within his territory. insects, frogs, lizards, snakes, young
nestlings, and small mammals
About ten weeks after mating, females lay their Breeding: Females lay 4–6 eggs
eggs in the soil or leaf litter or under a rock or a log. that hatch after 8–14 weeks
The hatchlings are about 4.5–5 inches long and look Life span: Not known
different from the adults. They are brown or olive, with Status: Common
white spots on their back and flanks. It takes about
three years for them to develop into mature adults. 115

The eyed lizards are the largest in their family in
Europe. The biggest males may grow to 2 feet or more.
Despite their size, these reptiles are timid creatures.

File snakes

The three species of file snakes take their name for their
rough skin, which is similar to the surface of a file. These
reptiles are also called wart snakes because their bodies
are covered in small, wart-like scales. File snakes live in

freshwater or saltwater and are helpless on land.

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File snakes are well suited to a life in the water. snakes and lizards
Their bodies are flattened from side to side and
have a keel, or ridge, of scales underneath. The keel Fact File
helps these snake to swim more efficiently. Their skin
is loose and baggy, allowing them to change their body File snakes
shape when swimming and push through the water Acrochordus arafurae,
quickly. A prehensile (gripping) tail allows these snakes A. javanicus, and A. granulatus
to hang on to underwater logs and plants, stopping Family: Acrochordidae
them from being swept away by strong water currents. Order: Squamata

File snakes can stay submerged for forty minutes or Where do they live?: From India
more, sealing their nose and mouth to keep the water and Sri Lanka across southeast
out. Their lungs are large and have a greater surface Asia to northern Australia and
area than those of other snakes. File snakes also have southern New Guinea
nearly twice as much blood as snakes of the same size
(apart from sea snakes), so their blood can carry twice Wart snake (acrochordidae)
as much oxygen. When they do come to the surface,
file snakes take several breaths for fifteen to twenty Equator Equator
seconds, then they dive underwater again.
Habitat: Fresh or brackish
Seeking Prey (slightly salty) water and seawater
File snakes rarely swim in open water. They prefer to
crawl over the ocean floor, using their long tongues to Size: Head–tail length 39 in. to
explore their surroundings and find food. File snakes 10 ft. (1–3 m); males are smaller
feed on fish such as eels. They hunt at night when the than the females
eels are asleep in their burrows. They grasp their prey
in their jaws and use their rough scales to hold the Coloration: Drab brown or gray;
victim in place as they squeeze it to death. The scales A. granulates is dark gray with bars
are rough because each one ends in a small bristle. of off-white on the sides

The Javan file snake is well-suited to a life Diet: Mainly fish, including eels
underwater. A flap in the upper jaw closes off
the nostrils when these snakes are submerged. Breeding: Females give birth to 11–
27 live young every few years

Life span: Not known

Status: Not endangered
or threatened

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Fire salamander

The bright colors of the fire salamander
warn other animals that it is poisonous.
This large, secretive amphibian spends most of
the day hiding under a log, in moss, or under

leaf litter. It emerges at night to feed.

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newts and salamanders

The fire salamander takes its name from the Fact File
belief that these amphibians could survive in a
Fire salamander
Salamandra salamandra
fire. This myth probably originated when people saw

European salamander & newt (salamandridae)the salamanders crawling out of logs that had been
Family: Salamandridae
thrown onto fires. This would have been seen as a sign Order: Caudata (Urodela)

that the salamanders had supernatural powers. In fact, Where do they live?: Europe;
closely related species live in
they were probably just hiding in the logs when they
north Africa and western Asia

were collected for firewood and were forced to emerge

to avoid being burnt by the flames.

Poison Packs Size: Head–tail length 7–11 in.
Fire salamanders are highly toxic. These amphibians (18–28 cm); weighs 0.6 oz. (19.1 g)
have large poison glands, called parotid glands, behind
each eye and two rows of poison glands along their Coloration: Jet black with bright
backs. The colored areas of the skin usually coincide yellow, red, or orange markings
with the location of these glands. The salamander’s
poison is so potent that it can cause convulsions Diet: Insects and worms
(muscle spasms). If they are attacked by a predator,
fire salamanders can squirt poison from their glands Breeding: Females usually give birth
at distances of up to 6 feet. They do this by squeezing to aquatic larvae; some forms give
the muscles around the glands. They even tilt their birth to live young
body so that streams of milky, sticky poison are aimed
at the predator. This is unusual because most other Life span: More than 14 years
salamanders can only release poison when a predator
bites or squeezes them. As well as repelling predators, Status: Lower risk—least concern
the fire salamander’s poisons may also work like
antibiotics, protecting its sensitive skin against attack
by microorganisms such as bacteria and fungi.

Most fire salamanders are black with yellow spots
and stripes. Others come in shades of red or orange,
although these are much rarer.

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Fire salamander

DKINDOYWO?U Lifestyle and Feeding sight. Fire salamanders eat a wide
Fire salamanders usually emerge at variety of prey, depending on where
The word night to feed. The eyes of the adults they live. Larvae and young adults
salamander are adapted to see best in dim light. usually eat whatever suitable prey
comes from During the night, adult salamanders is available in their habitat. The
an Arabic word, may wander up to 30 yards from Pyrenean fire salamander feeds
which means their daytime hiding places, but on earthworms, and many will eat
“lives in fire.” they always find their way back to nothing else. On the other hand, the
Salamander the same spot. The larvae also avoid central Spanish fire salamander lives
larvae may bright light and hide under stones around high mountain lakes where
eat each other and dead leaves during the day. there are no earthworms. It feeds
if larvae of When the weather is dull and rainy, mainly on beetles and flies.
different sizes however, adult fire salamanders may
live together. come out during the day. Courtship and Young
The venom from Fire salamanders are ready to breed
a fire salamander Fire salamanders use their senses when they are three or four years old.
will easily kill a of sight and smell when hunting for The breeding season usually starts
dog and possibly prey. The sense of smell is probably in the fall. Males claim areas, called
even a person. not as important as their sense of territories, and defend them from
Fire salamanders rival males. The older male usually
sometimes have wins these fights.
bright yellow skin
with no markings. During courtship, the male nudges
the female’s head and flanks before
moving under her body and looping
his front legs over hers from below.
He drops his sperm packet on the
ground and then swivels sideways
to allow the female to pick up his
sperm. Females can store sperm for
up to two and a half years. When

Fire salamanders are often found
on mossy tree trunks near water.

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newts and salamanders

Meet the family (S. atra) is found across the Alps. Lanza’s
alpine salamander (S. lanzai) is a close
There are four recognized species of relative but is larger and has a flattened
fire salamander. They are Salamandra head. It lives in the southern foothills of
salamandra from Europe, S. algira from the Alps in Italy and in parts of France.
North Africa, S. corsica from Corsica, and Another relation is Luschan’s salamander
S. infraimmaculata from the Middle East. (S. luschani), which lives in southwestern
Alpine salamanders are closely related to Turkey and islands off the Turkish coast.
fire salamanders and have now been split
into two species. The alpine salamander

they mate in the fall, the eggs are she keeps the larvae inside her body During
usually fertilized by the sperm the until they have changed into adults. mating,
following spring. The developing In this case, she gives birth to fully the male fire
young are held inside the female’s egg formed young. Fire salamanders from salamander
tube for up to a year in some cases. colder places, such as mountains, slides under the
are more likely to give birth to fully female’s body
The female usually gives birth formed young. The developing young and drops his
to larvae. She reverses into shallow are better protected inside their packet of sperm
water so the larvae can swim away mother’s body than they would be for the female
from her body to continue their outside in a harsher environment. to pick up.
development in the water. Sometimes

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Fire-bellied toads

The fire-bellied toads are named for their bright
red, orange, or yellow patches on their undersides.
An unusual feature is that the pupils in their eyes

are triangular or heart-shaped.

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Fire-bellied toads live in small groups, called frogs and toads
colonies, around a small area of water, such as
a pond or flooded field. These toads usually float on Fact File
the surface of the water with their legs outstretched. In
this position, their green and black backs provide good Fire-bellied toads
camouflage. When threatened, fire-bellied toads dive Family: Bombinatoridae (7–10
rapidly and bury themselves in the mud, or they swim species divided into 2 genera):
to the edges of the water to hide among the vegetation. Bombina and Barbourula
The webbed hind feet means these frogs are good Order: Anura
swimmers. When confronted by a predator, they may
show off their brightly colored bellies as a warning that Where do they live?: China, Europe,
they are poisonous and not good to eat. Korea, southern Japan, northern
Vietnam, Philippines, and Borneo
Species from the rare group Barbourula are in the
same family as fire-bellied toads, but they do not have Fire-bellied toad (bombinatoridae)
brightly colored undersides. They spend even more
time in the water and have flattened heads, webbed Tropic of Cancer
front feet, and large, webbed back feet for swimming.
Tropic of Cancer
Tiny Tongues
Many frogs and toads have long tongues that they Habitat: Forest clearings, peat bogs,
shoot out of their mouths to pick up prey from a pools, shallow lakes, streams, and
distance. Fire-bellied toads have short, rounded flooded fields in wetlands, scrubland,
tongues, so they cannot catch their prey in the same or forest clearings
way. Instead, these frogs are ambush predators. They
sit and wait until prey moves close by and then lunge Size: HeadÂ

Flying frogs

Flying frogs glide among the trees of the rain forest by
spreading out their huge webbed feet and using them like
parachutes to break their fall. Flying frogs stick their eggs to
leaves or tree trunks overhanging water. The tadpoles then

drop down into the water when they hatch.

124

Reinwardt’s flying frog and several of its close frogs and toads
relatives, such as Wallace’s flying frog and the
harlequin treefrog, spend most of their lives in the rain Fact File
forests, high in the treetops. These amphibians rarely
venture to the forest floor, except during the breeding Reinwardts’s flying frog
season. The only other time they might move to the Rhacophorus reinwardtii
forest floor is if they are chased by predators. In this Family: Rhacophoridae
situation, the frog jumps from a branch, holds its legs Order: Anura
out to the side, and spreads out its large webbed feet. Where do they live?: Southeast
As the frog glides through the air, it steers by changing Asia (Borneo, Java, Malaysia,
the position of its legs. The frog then lands on a branch and Sumatra)
or large leaves lower down the tree. The toes of these Habitat: Rain forests
frogs end in large sticky pads, similar to suckers, which Size: Head–body length 1.75–2.6 in.
help them to grip tightly when they land. (4.6–6.6 cm); females are usually
bigger than the males
Tadpole Homes Coloration: Bright or dark green,
Reinwardt’s flying frog breeds in shallow forest ponds, sometimes yellow on sides; webbing
often using the pools made by rhinoceroses or wild between the toes is yellow and blue
pigs when they wallow in the mud to cool down or or black and blue
remove pests from their skin. Other species from the Diet: Insects
group Rhacophorus lay their eggs over flowing streams, Breeding: Eggs laid in a foam nest;
and their tadpoles live in the spaces between rocks and later hatch into tadpoles
stones, or in quiet streamside pools full of dead leaves Life span: Not known
and other debris. The brown treefrog sticks its eggs Status: Lower risk—least concern
to tree trunks above holes full of water, or the pools
formed between the large, flat buttress roots of the 125
giant forest trees. When the eggs hatch, the tadpoles
of the flying frogs have rounded bodies and high fins.

Flying frogs such as Wallace’s flying frog cannot
fly. They glide like parachutes, using the webbing
between the toes and skin flaps on the arms and legs.

Flying lizards

Flying lizards live on the trunks of large trees in the rain
forests of southeast Asia. Using their collapsible

“wings,” these reptiles glide from tree to tree. Other
gliding reptiles include flying geckos and snakes.

126

The wings of the flying lizards are not true wings, snakes and lizards
like those of a bird. Instead, they are formed from
flaps of skin on each side of the body and supported Fact File
by extra-long ribs. When a flying lizard wants to glide,
it drops down at a steep angle with its wings folded COMMON FLYING dragon
and its tail raised. The lizard then opens its wings and Draco volans
lowers its tail to slow down the descent. Flying lizards Family: Agamidae
glide almost horizontally, using their tails as rudders to Order: Squamata
steer, and their wings and tails as brakes. After landing Where do they live?: Southeast
on a tree with their heads up, these lizards fold their Asia (Borneo, Indonesia, Malaysia,
wings up like a fan. The flying lizard then runs up the and the Philippines)
tree to make up the height that it lost during the glide. Habitat: Rain forests
Flying lizards can glide for up to 50 feet or more but Size: Head–tail length 6–8 in. (15–
they normally glide for much shorter distances—often 20 cm); females are slightly larger
only a few yards from one tree to the next. than the males
Coloration: Wings are mottled
Female Flyers orange and black; males have a
Female flying lizards have larger wings than the males. yellow dewlap (throat flap) and
The extra surface area may help the females to glide females have a blue dewlap
when they have the additional weight of their eggs Diet: Mainly ants and termites
inside their bodies. Females descend to the forest floor Breeding: Females lay 3–6 eggs
to lay their eggs. They are vulnerable to predators and bury them in the ground;
at this time because they cannot move very well in eggs hatch after 32 days
the leaf litter. The females lay small clutches of long, Life span: Not known
spindle-shaped eggs. The eggs have hard caps at each Status: Common
end. This egg type is unique to flying lizards. No one
knows the reason for the shape. The behavior of the 127
flying lizard hatchlings in the wild is also a mystery.

The common flying dragon glides through the air.
Flaps of skin along the sides of its body act like
a parachute to slow the lizard’s descent.

Frogs and toads

Frogs and toads were the first To zoologists, there is not a great difference
animals on the Earth to have a between frogs and toads. Frogs and toads
true voice. These amphibians are come from the large group Anura, and they are
often heard calling, especially in often called “anurans.” The main distinction
the breeding season. There are between frogs and toads is their skin. Toads
about 4,800 different species are usually dry, warty species that run or walk.
of frogs and toads, making up 88
percent of all amphibians. The red-eyed treefrog is a striking species that
lives in the rain forests of Central America.

128

Frogs have smooth, damp skins, live near the Fact File
water, and move by leaping. Another way of
distinguishing frogs and toads is to think of Frogs and toads
all amphibians without tails as frogs and use
the word “toad” for members of certain families, Families: There are 28 families divided into
such as the Bufonidae. about 346 genera, including Leptodactylidae
(about 1,110 species of rain frogs); Bufonidae
The toad family Bufonidae is one of the most (about 454 species of true toads and harlequin
successful of all the frog and toad families. It has toads); Hylidae (835 species of treefrogs,
more than 450 species that live in every part marsupial frogs, and leaf frogs); Ranidae
of the world apart from Antarctica. Hylidae is a (729 species of water frogs); Microhylidae
successful frog. It contains around 835 species of (358 species of narrow-mouthed frogs).
treefrogs, marsupial frogs, and leaf frogs living in
most parts of the world, except Africa. Although Order: Anura
there are more than 1,100 species of rain frogs,
most of them live in Central and South America. Where do they live?: Every continent apart
froFmrogsAandtatoracdtsica
Tropical forests are home to the greatest
numbers of anurans. A few acres of tropical Equator Equator
forest in South America may contain as many
as 80 different species, which is the same Habitat: Most habitats except polar regions
as the total number of species found in the and very dry deserts
United States. The island of Madagascar off the
southeastern coast of Africa is also home to a Size: Head–body length 0.2–34.5 in.
huge variety of species, nearly all of which are (1–88 cm); most 0.8–4.75 in. (2–12 cm);
unique to the island. Tropical forests are ideal largest species weigh up to 8 lb. (3.6 kg)
places for frogs because they are warm and
moist, there are plenty of places in which to Coloration: Green, brown, gray, black, red,
hide from predators, and there are many insects orange, yellow, or even blue
and other invertebrates for them to eat.
Diet: Adults eat plants, invertebrates, small
Body Forms vertebrates, and carrion (dead animals);
The body shapes of frogs and toads suit the tadpoles eat plants and small invertebrates
environments in which they live. For example,
the spadefoot toads have powerful legs that end Breeding: Females lay eggs in water or on
with horny “spades” that are used for digging. moist ground; eggs develop in or on one of
Other species have pointed snouts, which are the parents; most species hatch into tadpoles
but some develop inside the egg and hatch
as small froglets

Life span: 1–10 years in captivity, although
some may live more than 35 years

Status: Varies according to species

129

Frogs and toads

Treefrogs and other climbing species have used to burrow headfirst through the soil.
suckerlike pads on the tips of their toes that help Swimmers also have pointed snouts, as well as
them to cling on to slippery branches. webbed feet and streamlined bodies to glide
effortlessly through the water. The African
ghost frogs have huge pads on their toes to
help them cling to slippery rocks behind
waterfalls. In dry climates, frogs with short,
stout bodies survive well because they have
a relatively small surface area. This reduces the
amount of water they lose through their skin.

Skin Secrets
Frogs and toads breathe through their skin as
well as through their lungs. The skin must be
kept moist to allow oxygen to enter the body
and waste carbon dioxide to leave. Glands keep

Waxy coat

The waxy frog (right) from the dry Chaco
region of South America has a clever way
of surviving the dry season. It covers
itself with a waxy substance produced
from glands in its skin. It wipes the wax
all over its body using its long, back legs.
This creates a waterproof layer that holds
in moisture and prevents the frog from
drying out. Most frogs live in the tropics
because the air is so humid. They do
not need to be near water to keep their
skin moist. It is much easier for a frog to
survive in a damp place than a dry place.

130

Frogs and toads

their skin moist, but in very dry conditions, The cane toad eats prey that has been killed
frogs and toads lose too much water and by other animals, which is known as carrion.
dehydrate. Species that live in the desert and
other dry places have fewer moisture-producing DID YOU KNOW?
glands in their skin, so they do not dry up as
quickly. However, this also means they cannot The biggest froglike amphibian is the
breathe through their skin as efficiently, so they Goliath frog, which is 34.5 in. (88 cm)
need larger lungs. long. The smallest is probably the Cuban
leaf litter frog, at only 0.33 in. (1 cm) long.
Extreme Survival The skin of the yellow poison dart frog
Frogs and toads living in arid places often exudes enough poison to kill up to
spend the dry season underground to avoid 1,000 people.
drying out. Some species form cocoons of mud Some frogs have bright colors to warn
that bake hard around their bodies and seal in other animals to leave them alone
the moisture. They only come to the surface because they are poisonous.
when heavy rain breaks up the mud and allows
them to escape. Species from cold places, high 131
in the mountains, often have dark skin. This
helps their bodies to absorb as much heat as
possible on sunny days and also protects them
from the Sun’s harmful radiation, which is
much stronger at higher altitudes.

Most parts of the world have at least one
“urban frog” species that lives in drains, garden
ponds, and greenhouses. Some species travel
with greenhouse plants and crops when they
are sent to markets or shops, and end up
hundreds of miles away from their homes.

Food and Feeding
All adult frogs and toads are carnivores (meat-
eaters). They prefer to eat living, moving prey.
The choice of prey depends largely on its size

Frogs and toads

and availability, but frogs and toads are not very debris. Some filter food from the water instead.
fussy eaters. Anurans do not chew their food. As they grow, the mouthparts of the larvae
Instead, they swallow it whole. Frogs and toads become more powerful, and they may switch
will try and eat more or less anything they can to plant leaves and stems. Eventually, they may
fit in their mouths. snap up invertebrates that live in the water or
are unfortunate enough to fall into the water.
Different species find and catch prey in A few tadpoles even eat the eggs of other frogs.
different ways. Larger species tend to sit and When food is particularly scarce, some tadpoles
wait for their prey to pass by them. They often may eat other tadpoles.
have camouflage colors or hide under leaves or
moss. Smaller species are usually more active Life Cycles
and spend hours searching in crevices and The life cycles of frogs and toads vary
under leaves in the hope of finding small insects between different species. The typical life
and other invertebrates. Many species have cycle of a European common frog starts in
long tongues that are folded on the base of the the spring. Males start to call from breeding
mouth, with the tip pointing back toward the ponds to attract the females. Nearly all anurans
throat. The frog flicks out the tongue quickly to that mate in the water pair up with the male
pick up passing prey. Some burrowing species clinging to the back of the female. This position
even live in the nests of their prey. is called amplexus, and it is the best position
for the male to fertilize the eggs as they are
The larvae (tadpoles) of most frogs and toads being laid. The eggs then begin to hatch into
use several rows of rasping teeth to scrape algae free-swimming tadpoles that grow legs, lose
and bacteria from leaves, rocks, and underwater their tails, and emerge onto land as adults.

DID YOU KNOW? Variations on this typical life cycle include
that of the midwife toad, in which the male
The common toad lives at altitudes carries a string of eggs wrapped around his
of more than 26,000 ft. (8,000 m) back legs. In the marsupial frogs, the female
in the Himalayas of Central Asia. carries the eggs around with her. Frogs and
toads that live in places where there are no
When food is scarce, tadpoles may suitable ponds or streams may lay eggs that
eat other tadpoles, sometimes even hatch into miniature versions of the adults.
their own brothers and sisters! The tadpole stage occurs inside the egg before
it hatches. Other species carry their developing
The tadpoles of poison dart frogs
eat special eggs that their mother
lays for them.

Newly hatched Gardiner’s frogs are
about the size of a grain of rice.

132

Frogs and toads

young inside their bodies, for example, in their their bodies until they have developed into
mouths, stomachs, or inside the female’s egg fully formed frogs or toads.
tubes. The adults do not let their young out of

Frog life cycle the tadpole goes through a dramatic
change called metamorphosis. It grows
When it hatches, a common frog looks four legs, loses its tail, and starts to
very different from its parents. It is a breathe using newly developed lungs
tadpole. It has no legs—just a large head, inside its body.
a tail for swimming, and gills to take in
oxygen from the water. Over 16 weeks,

Day 1: Tadpole breathes through its Year 4:â•‹The adult frogs
skin. It feeds on yolk in its stomach. mature and are ready to
produce young of their own.

Days 2–3: Tadpole starts to ONâ•‹LAND Week 16: Tadpole is now a
swim and feeds on plants. IN WATER tiny frog without a tail. The
It breathes through feathery young frog leaves the water but
gills outside its body. remains nearby for some time.

Week 3: Tadpole has grown Week 12: Tadpole has
bigger and breathes through front and back legs, a
gills inside its body. shorter tail, bigger eyes,
and a wider mouth.
Weeks 8–10: Tadpole has back legs and
breathes air from the surface using lungs inside
the body. It starts to eat meat instead of plants.

133

Galápagos giant tortoise

The largest tortoises in the world live on the Galápagos
Islands in the Pacific Ocean. These reptiles probably

drifted across the ocean from Central America, perhaps
on floating tree trunks. The biggest Galápagos tortoises
weigh as much as three men and may live for 200 years.

134

turtles, terrapins, tortoises

The Galápagos Islands were formed when Fact File
volcanoes erupted through the seafloor about
600 miles off the coast of Ecuador in northern South Galápagos giant tortoise
America. The first giant tortoises washed up on the Geochelone nigra
beaches of the island of Española. Later, more giant Family: Testudinidae
tortoises landed on the islands of southern Isabela, Order: Testudines
Volcan Darwin, and Volcan Alcedo. A third batch of
tortoises landed on other islands in the group. Where do they live?: Galápagos
Islands in the South Atlantic
It may seem unlikely that tortoises could just drift
across the ocean for hundreds of miles and end up on Habitat: Upland areas
some remote islands. Yet tortoises are often carried far
from land during floods and they can survive very well Size: Shell length from 29 in.
at sea. They stay afloat with little effort, bobbing along (74 cm) to more than 4 ft. (1.2 m);
on the ocean waves. They can survive for long periods weighs 500 lb. (227 kg)
without eating. They use the stores of body fat to
supply them with energy. One female is all that is Coloration: Dull brown; males often
needed to start a new population of tortoises if she have a yellow area on the
already carries a male’s sperm inside her body. Female lower jaw and throat
tortoises can lay eggs for up to four years without
a male being present. The young giant tortoises on Diet: Wide range of vegetation—
the Galápagos Islands would have hatched in a safe even cactus shoots
environment, with plenty to eat and few predators,
allowing their numbers to build up very quickly. Breeding: Females lay 2–10 eggs
that hatch after 3–4 months
Three Types of Tortoise
Scientists put the different groups of Galápagos giant Life span: Up to 200 years
tortoises into three separate groups based on the way
in which they have adapted to their environment. Status: Vulnerable

Galápagos tortoises with saddleback shells have
longer necks and legs. They need to stretch to reach
tall vegetation on the dry islands on which they live.

135

Galápagos giant tortoise

A male calls The first group is the saddlebacks. where there are plenty of lush plants
loudly to They are named for the way the front at ground level. The third group
attract a of their shells rise up above their includes tortoises with characteristics
female to mate. necks, similar to a horse’s saddle. partway between the saddlebacks
These tortoises live on dry islands and the dome-shelled tortoises.
where they need to stretch up to feed
on taller plants. The smaller plants Island Races
on these islands die back during dry Several groups of the Galápagos giant
periods. Saddlebacks have long legs tortoise live isolated from each other
and long necks, so they can stretch as on the twenty different islands in the
high as possible. The second group Galápagos group. Each group has
is the tortoises with dome-shaped adapted to the different conditions
shells and short necks. This group on the islands. The shape of their
lives on upland areas of the islands, shells, their maximum size, and the
lengths of their necks and limbs
vary according to where they live.
These differences helped the British
naturalist Charles Darwin to figure
out his ideas on evolution when he
visited the islands as the zoologist
on board the HMS Beagle in 1835.

Tortoise Troubles
In the nineteenth century, many
Galapágos giant tortoises were taken
from the islands and used to feed the
crews of European whaling ships.
So many tortoises were taken that
three groups became extinct—on
Charles Island, Barrington Island,
and Narborough Island. Hunting is
now banned, and the tortoises are
fully protected by laws passed by the

136

turtles, terrapins, tortoises

mating games

The courtship rituals of the Galápagos
giant tortoises are extremely aggressive.
The larger male tortoises bash the shells
of the females and pin them down by
clambering on top of them. The males
often make a roaring sound when they
mate with the females. The females lay
between two and ten hard, spherical
eggs from July to December. The young
tortoises hatch during the rainy season
when there is fresh grass and plenty of
other vegetation to eat.

DKINDOYWO?U government in Ecuador. However, Male tortoises stretch their long
the Galápagos giant tortoises still necks and rise up on their legs in
Galápagos giant face many problems. Goats left on a display of dominance. The taller,
tortoises move the islands by sailors long ago now larger male usually earns the right
at speeds of compete with the tortoises for food to mate with the female.
about 590 and can destroy their nests as well.
yards (550 m) Other introduced species include tortoises. These tortoises are also
every hour. pigs and rats, and these eat the being bred in captivity. Over the last
tortoises’ eggs. forty years, the Darwin Foundation on
A giant tortoise the Galápagos Islands have hatched
can live without Saving the Tortoises more than 2,500 young tortoises,
food for up to Many conservation programs have adding to a total population of about
14 months. been set up to help the Galápagos 10,000 individuals. The tortoises are
giant tortoises. The introduction of kept safely in pens and protected from
The shell of a foreign species is being controlled predators, such as birds of prey, until
newly hatched to prevent competition for food they are three years old. Then they
giant tortoise or danger to the eggs and young are released into the wild.
measures only
2.5 in. (6 cm)
in length.

137

Garden lizard

Garden lizards are found throughout the warmer parts
of southern and southeast Asia. They are also called

changeable lizards as they can change color. Males take
on a bright red body color during the breeding season,

giving rise to their other name “bloodsuckers.”

138

The garden lizard lives in a wide range of habitats snakes and lizards
across Asia and adapts well to living near people.
It is active during the day and is often seen resting on Fact File
tree trunks and bushes, even near busy roads. Unlike
other lizards, the tail of a garden lizard does not break oriental garden lizard
off if it is attacked by a predator. The tail can be long, Calotes versicolor
stiff, and pointed. Both males and females have a crest Family: Agamidae
along the top of the body. Order: Squamata
Where do they live?: Middle East,
Courtship and Eggs India, Sri Lanka, Indochina, South
During the breeding season, males are very aggressive. China, and Sumatra; also Andaman
They develop a bright red head, throat, and shoulders. Islands, Mauritius, and the Maldives
These colors become brighter if a male is winning a Habitat: Open forests, gardens,
fight with a rival, while the defeated males lose their parks, and the edges of fields
bright colors. Males attract females to their territory Size: Head–tail length up to 20 in.
by extending a pouch in their throat called the gular (51 cm)
pouch, while doing “push-ups” and opening and Coloration: Light brown to buff,
shutting their mouth rapidly. sometimes faint dark bands; males
develop red chests and throats
Females store energy as fat in the bodies to help them during breeding season
produce their eggs. They can also store sperm and keep Diet: Small invertebrates
developing eggs in their egg tubes. As a result, they can Breeding: Females lay 10–20 eggs
lay their eggs when the young lizards are most likely that hatch after 6–7 weeks
to survive. The female slows the development of eggs Life span: 2–4 years
inside her body so that they do not become too big Status: Widespread
to be laid. She does this by lowering the temperature
of her body to 73ºF. Both males and females only 139
produce eggs and sperm if they are with members
of the opposite sex and therefore able to mate.

The Oriental garden lizard is a common sight in
many parts of Asia. The throat of the male turns
bright red in the breeding season to attract females.

Garter snakes

The common garter snake is active during the day.
The body stripes of these snakes blend in well with the
surroundings, making it surprisingly difficult to see them
in the wild. These reptiles are named for the patterns on

old-fashioned garters, used to hold up stockings.

140

Garter snakes live over a wide area of North snakes and lizards
America, and they come in many different
colors. The endangered San Francisco garter snake has Fact File
a red head and bright red stripes edged in black on
either side of a white central stripe. (Most garter snakes Common garter snake
have this white central stripe.) The California red- Thamnophis sirtalis
sided garter snake and the Oregon red-spotted garter Family: Colubridae
snake also have large areas of red on their bodies. The Order: Squamata
northern red-sided garter snake has red spaces between Where do they live?:
its black scales. The red only shows when the skin is North America
stretched, for example, when it flattens its body if it Habitat: Ponds, streams, and
is threatened by a predator. All-black garter snakes water-filled ditches in dry regions;
usually live in coastal areas and islands, including damp meadows, marshes, parks,
the islands of the Great Lakes. and gardens
Size: Head–tail length 18 in.
Varied Diet (45 cm) to 4.25 ft. (1.3 m)
Garter snakes eat a wide range of animals, including Coloration: Several long stripes
earthworms, leeches, fish, and frogs. Some hunt small from neck to tail; width and color
fish in tidal pools on the beach. Others eat California of stripes vary with location
newts, which are poisonous. Scientists think that the Diet: Invertebrates such as worms,
adult garter snakes somehow pass on immunity to the amphibians, and fish; larger snakes
newts’ poison to their young. eat young birds and small mammals
Breeding: Females give birth to
Garter snakes hunt mainly by sight, but they need 10–30 live young that are born
to be stimulated by smell before they will strike their after gestation period (pregnancy)
prey. These snakes eat prey, such as worms, that cannot of 60–90 days
fight back, so they usually just grab and swallow their Life span: Captive garter snakes
meals. Garter snakes are not poisonous and constrict live for up to 10 years
(squeeze) their prey to death. Status: Lower risk—least concern

Common garter snakes do not lay eggs like most 141
other reptiles. Instead, the females give birth to
live young around three months after mating.

Garter snakes

A garter snake
eats a northern
leopard frog.
Snakes usually
swallow their prey
headfirst.

DID YOU Hibernation ant mounds are also good places
KNOW? In warmer parts of their range, garter in which to gather. The number of
snakes are active all year. In very cold garter snakes at these hibernation
Between 35 and areas, these snakes enter a period of sites range from a few hundred to
50 percent of deep sleep, called hibernation, for several thousand individuals. The
garter snakes several months during the winter. snakes stay together because there is
do not survive a shortage of good hibernation sites.
the winter. Hibernating in numbers also means
the snakes can share their body
Some hibernation During hibernation, the snakes can warmth, and it stops their bodies
dens may contain survive temperatures close to freezing from drying out.
up to 10,000 because they shut down essential
garter snakes. body processes. The blood thickens Developing Young
Some females as it starts to freeze, and the body Males feed throughout the summer
give birth to temperature falls. Garter snakes to build up fat reserves that will
eighty young have small amounts of “antifreeze” last them through the next winter’s
snakes at a time. hibernation. Females stop feeding
when their developing young begin
chemicals, mainly in their liver and to take up space inside their bodies.
The young take in nourishment from
heart, that stop their cells from

freezing solid. Even so, many garter

snakes die during hibernation.

Garter snakes usually gather

in large groups to hibernate. They

migrate to limestone caves where the

frost cannot reach them. Abandoned

142

snakes and lizards

their mother’s blood, which also Breeding patterns
takes waste products away from the
developing snakes. In colder climates, Common garter snakes from different places
young snakes have a better chance of have different breeding pattern. In the far north,
survival if they stay inside the body garter snakes breed for a few weeks directly after
of their mother rather than develop they emerge from hibernation. Females give off
inside eggs. The female can bask in a scent containing a pheromone that attracts the
the sunlight to help the young snakes males. There is huge competition between males.
develop. The babies are also protected They form “mating balls” around each female.
inside their mother’s body from Each male rubs his chin along the female’s back
predators. However, the extra weight and tries to mate with her. One male succeeds,
of the babies makes the female leaving a waxy plug in the female to stop other
sluggish and slow-moving. males from mating with her. He can then move
on and mate with other females. Females move
About eight to twelve weeks after to their summer feeding sites as soon as they have
mating, the female will usually give mated. Feeding sites can be up to 11 miles away
birth to ten to thirty young. The from the hibernation sites. The males do not
newborn snakes can survive on their leave until all the females have gone.
own as soon as they are born. Almost
immediately, the young snakes start
to hunt for food to fatten up as much
as possible in preparation for the
winter hibernation. Females that
have carried their young throughout
the spring and early summer have
had little time to build up their fat
reserves. For this reason, it seems
likely that garter snakes living in the
colder northern regions breed only
every second year. In the warmer
southern areas, garter snakes have a
longer summer season in which to
feed and can breed every year.

143

Geckos

Geckos are small lizards. They They often use their long tongues to wipe their
are named for the distinctive eyes clean. In bright light, the pupils of night-
“gekok” noise made by some active geckos close down to vertical slits to stop
species when they call. Geckos the light from damaging their eyes. The colored
usually emerge at night to part of the eye, called the iris, can have delicate
forage for insects, spiders, and and attractive markings. Some of the species in
other small invertebrates. Some the Gekkonidae family are active during the day.
species are spectacular climbers. They have smaller eyes and round pupils.

Of the three main gecko families, the one Feet and Toes
with the most species is the Gekkonidae. Gekkonid species have a variety of different feet
Nearly all the species from this family have and toes that are suited to the ways in which
small, granular scales. A few species, such as the they move. Many “house” geckos are brilliant
frog-eyed geckos and the fish-tail geckos, have climbers. They can run up any vertical surface,
larger overlapping scales. Most of these geckos
emerge at night to hunt for food, so their eyes Dark spots cover the head and body of the
are large to let in as much light as possible. leopard gecko. The pattern varies among
different lizards, however, and some have no spots
at all.

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rough or smooth, and even rest upside down Fact File
on ceilings. These lizards have toe pads with
special structures called lamellae arranged in Geckos
rows along each toe. Each lamella consists of
thousands of hairlike cells, called setae. In turn, Families: 3 families divided into 95 genera:
each seta is further divided into even smaller Gekkonidae (about 910 species of typical geckos
branches. Each of these branches ends in a and American dwarf geckos); Eublepharidae
slightly swollen tip. There may be up to one (22 species of eyelid geckos); Diplodactylidae
billion of these tips on each toe. They interact (about 115 species of “southern” geckos)
with the surface on which the gecko is moving,
allowing the lizard to “stick” to it. When the Order: Squamata
gecko wants to move its foot, it has to curl up
the ends of its toes to “unstick” them. Where do
they live?:
Other gekkonids have claws instead of sticky Gekkonidae:
pads to help them climb among the branches worldwide, except
of trees and bushes. These include members of the polar regions; Equator
the group Cyrtodactylus (“curved toe”) and the Eublepharidae:
group Gymnodactylus (“naked toe”). Ground North America,
geckos do not climb at all. These lizards include Central America, Africa,
species from the groups Chondrodactylus (“grain Middle East, Japan, eastern China, Malaysia;
toe”), and Pachdactylus (“thick toe”). They are Diplodactylidae: Australia, New Zealand, and
common in desert regions, where there is often New Caledonia
nothing for them to climb. Ground geckos prefer
to live in burrows or the spaces between rocks. Habitat: Varies from forests to urban habitats
Some of them have large heads with powerful
jaws for crushing insects with hard bodies, such Size: Head–body length 2–13 in. (5–33 cm);
as beetles. In Africa, barking geckos have fringes weight 0.02–10.5 oz. (1–300 g)
of hairlike scales around the edges of their feet
to prevent them from sinking into the desert Coloration: Nocturnal (night active) geckos
sands. All the ground geckos are active at night. usually gray or brown with mottled markings;
diurnal (day active) geckos vary from bright
Southern Geckos green with red markings to bluish green, yellow,
Members of the Diplodactylidae family are or black-and-white; males may be more brightly
called “southern” geckos because they live only colored than females
in the Southern Hemisphere. These lizards are
Diet: Typically small invertebrates; larger
species eat other lizards, small snakes, birds,
and small mammals; diurnal geckos also eat
fruit, pollen, and the nectar from flowers

Breeding: Most females lay 1–2 eggs that
hatch after 5–8 weeks; some “southern”
geckos may give birth to live young after a
gestation period of up to 14 months

Life span: 5–25 years

Status: At least two species are critically
endangered, four are endangered, and nine
are vulnerable

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Geckos

common in Australia, New The common barking gecko lives
Zealand, and New Caledonia in the Kalahari and Namib deserts
(an island in the Pacific Ocean of southern Africa. It hides in burrows
to the east of Australia). They to escape the hottest parts of the day.
include several unusual species,
such as the New Zealand Hoplodactylus Eyelid Geckos
and Naultinus geckos, which all give birth All the members of the Eublepharidae family
to live young instead of laying eggs. Southern have movable eyelids. None of them have sticky
geckos live in a wide range of habitats, from toe pads. They usually lay their eggs in pairs.
deserts Like the southern geckos, the eggs of these
to dense forests. Southern geckos called velvet geckos have rubbery shells that absorb water
geckos prefer specific habitats. Some live under during their development.
the bark of fallen trees, while others prefer
standing trees. Still others make their home All eyelid geckos live on the ground, except
under flakes of broken rocks. for the cat gecko from Malaysia. This strange
gecko has a prehensile tail that it holds in a
The aptly named fringe-toed velvet gecko has coiled position as it moves slowly along twigs.
a fringe of scales around its toes and a gripping, Species from North America, Africa, and the
or prehensile, tail to help it climb. The jeweled Middle East live in dry habitats. Species from
gecko from Australia and the day geckos from Central America and Asia live in rain forests.
New Zealand also have prehensile tails. The Species from China and Japan prefer to live in
fringe-toed gecko, the New Caledonian geckos, cool, moist habitats, especially in caves. Even
and the pad-tailed gecko even have sticky pads though there are only twenty species of eyelid
on the tips of their tails as well as on their toes. geckos alive today, they live in many different
parts of the world. Scientists think that these
DID YOU KNOW? species are all that remains of a much larger
family that was once more widespread.
Typical geckos have no eyelids, but
members of the family Eublepharidae
have movable eyelids.

Web-footed geckos have webbed feet
to help them run across loose sand
without sinking.

Wonder geckos and the viper gecko
make a sound by rubbing the scales
on their tails together.

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GECKOS

Threats to Survival the gecko’s prime habitats. The Paraguanan
There are more than 1,000 species of geckos. ground gecko and a species known by the
Many species are thriving, but some are on the Latin name Phelsuma antanosy are both listed
brink of extinction thanks to human activities as Critically Endangered by the International
such as deforestation. These activities destroy Union for the Conservation of Nature (IUCN).

Terrific tails

When a predator grabs them, many those from very dry places, have thick,
geckos can break off their tails to make carrot-shaped tails that are used to store
their escape. The gecko then grows a food. This helps the geckos to survive
new tail as a replacement. The tail of when food is scarce. The flat tails of the
a gecko may help it to survive in other Madagascan and Australian leaf-tailed
ways. Some species, such as the leopard geckos can be pressed against tree trunks
gecko, have black-and-white tails that when they rest to cut out shadows. This
attract attention. The distinctive tails of provides excellent camouflage. Asian
these geckos help to keep predators away flying geckos even have fringes around
from more vulnerable parts of the body, the edges of their tails that help them
such as the head. Other geckos, especially to glide through the air.

The fat-tailed gecko from Africa
uses its thick, stumpy tail to store
fat. The fat store will see it
through the times when
food is scarce.

147

GHArIAl

with its unmistakable narrow snout, the gharial is one
of the largest members of the crocodile family. this giant

is a danger only to fish in the rivers of india
and neighboring countries in which it lives.

148

Gharials are large reptiles with distinctive narrow CrOCODilians
snouts and longer legs than their relatives—the
alligators and crocodiles. The male is bigger than the fact file
female and has a swollen end to his snout. The shape
of the snout looks like rounded cooking pots, called GHarIal
gharas, which are used in parts of northern India. This Gavialus gangeticus
is where the gharial gets its common name. family: Crocodylidae
Order: Crocodylia
Adult gharials hunt in fast-moving rivers. They swim Where do they live?: Northern
using their webbed back feet and their wide, long tails. India and Nepal and other parts
Gharials lie on the riverbed with their mouths wide of the Indian subcontinent
open. When a fish swims by, it quickly moves its head Habitat: Rivers
through the water and snaps its jaws around its prey. size: Head–tail length 10–21 ft.
The gharial comes to the surface and raises its head (3–6.4 m); weight: up to 2,200 lb.
out of the water before swallowing its food. Otherwise (977 kg)
it would swallow too much water with its meal. appearance: Olive-green or tan
with dark bands and blotches
Breeding season across the body
Gharials live alone, but males and females meet to Diet: Mostly fish; some individuals
breed between November and January. The male blows eat water birds or are scavengers
bubbles through his swollen snout to attract and mate of dead animals
with the female. The female then digs her nest on land Breeding: Female lays 28–43 eggs
near the river in which she lives. She buries her eggs in that hatch after 2 to 3 months
the nest and only digs them up when she can hear the life span: 40–60 years
hatchlings calling her. each one is about 14 inches long status: Critically endangered
at birth. She carries them to the river, and they swim
off to fend for themselves. young gharials hunt insects, 149
frogs, and small fish. They move onto larger prey, such
as catfish, when their mouths are big enough.

A gharial has 102 razor-sharp teeth that curve
outward and forward to grip even the most
slippery, fast-moving fish.