The Animal Kingdom
There are many different types of animals in the world. Many
animals are quite similar to each other.Others are quite different.Animals can
be classified based on their similarities. Invertebrates Animals without a
Backboneor Spinal Column: Vertebrates Animals with a Backbone or Spinal
Column:(All these are those animals are in the phyla Chordata and the subphyla
Of the million or more animal species in the world, more than
98% are invertebrates. Invertebrates don’t have an internal skeleton made of
bone. Many invertebrates have a fluid-filled, hydrostatic skeleton, like the
jelly fish or worm. Others have a hard outer shell, like insects and
crustaceans. There are many types of invertebrates. The most common
invertebrates include the protozoa, annelids, echinoderms, mollusks and
arthropods. Arthropods include insects, crustaceans and arachnids.
Protozoa are simple, single-celled animals. They are the
smallest of all animals. Most protozoa are microscopic in size, and can only be
seen under a microscope. However, they do breathe, move and reproduce like
There are several types of protozoa. The amoebas are clear, shapeless cells.
Flagellates have a body shape looking like a hair. Although we can’t see them,
protozoa do a lotfor us. Protozoa play a useful role in the food chain as a
source of food for fish and other animals. Some protozoa are helpful to humans
by eating dangerous bacteria. Unfortunately, other protozoa are parasites and
can be harmful to humans by transmitting disease.
Protozoa eat tiny algae and bacteria. Some protozoa absorb food through their
cell membrane. Others surround and engulf their food or have openings to collect
food. They digest their food in stomach-like compartments called vacuoles.
Protozoa take in oxygen and give off carbon dioxide through the cell membrane.
Protozoa reproduces by splitting in half.
(II) WORMS AND LEECHES
There are about 9,000 species of Annelids known today,
including worms and leeches. They can be found almost anywhere in
theworld.Annelids have existed onEarth for over 120 million years. Annelids have
bodies that are divided into segments. They have very well-developed internal
organs. One common characteristic of annelids is that they don’t have any limbs.
Some annelids may have long bristles. Others have shorter bristles and seem
smooth, like the earthworm. There are many types of worms.Commonly known worms
include earthworms, roundworms and flatworms. Most worms are small, measuring
fractions of an inch to several inches long. Other worms, such as the ribbon
worm, can grow up to 100 feet in length. Some worms are considered parasites, in
that they live inside the human body.
Mollusks were among the first inhabitants of theEarth.
Fossils of mollusks have been found in rocks and date back over 500 million
years. Mollusk fossils are usually well preserved because of their hard shell.
Most mollusks have a soft, skin-like organ coveredwith a hard outside shell.
Some mollusks live on land, such as the snail and slug. Other mollusks live
inwater, such as the oyster,mussel, clam, squid and octopus.
Land living mollusks, like the snail, move slowly on a flat sole called a
foot.Ocean living mollusks move or swim by jet propulsion. They propel
themselves by ejecting water from their body. For example, the squid ejects
water from a cavity within its body, and the scallop ejects water tomoveRS.
by clamping its shell closed.Other ocean living mollusks, like the oyster,
attach themselves to rocks or other surfaces, and can’t move. They feed by
filtering small food particles from water that flows through them.Snail and
SlugThe snail family consists of marine snails and land snails all over the
world.Land snails live in many habitats from gardens and woodlands, to deserts
andmountains.Marine snails are native to all theworlds oceans and seas, andmany
freshwater rivers and lakes. Along with slug, snails make up the gastropod class
of the mollusk phylum. Snails have an external shell, large enough to withdraw
their body into it. Gastropods without a shell are known as slugs.
There are about 300 different species of octopus native to
many of the world’s oceans, especially coral reefs. The octopus doesn’t have an
internal or external skeleton,allowing it to squeeze into very small places. The
octopusRS. has eight arms or tentacles, that it uses for crawling, exploring
things and catching prey. The octopus’ arms have suckers capable of grasping and
holding objects, such as their prey. The octopus has a hard beak in the center
of its arms that it uses to tear apart its prey for eating. Like the squid, the
octopus can suck water into its mantle and expel it out in a fast, strong jet.
This jet propulsion provides fast, forward movement. Also like the squid, the
octopus can eject a thick cloud of ink to help it escape from predators.
There are about 300 species of squid. They are native to most
of the world’s oceans. The squid has a distinct head, eight arms and two
tentacles. The mouth of the squid has a sharp horny beak used to kill and tear
its prey into small pieces. The main body of the squid is enclosed in the
mantle, which has a swimming fin along each side. However, the swimming fin is
not the squid’s main way of moving through the water. The squid can suck water
into the mantle and expel it out in a fast, strong jet. This jet propulsion
provides fast, forward movement. Although most squid are less than 2 feet in
length, the giant squid can grow up to 43 feet in length.
Despite their name, the cuttlefish is not a fish, but a
mollusk. The cuttlefish is native to all of the oceans of the world, but are
more common in shallow coastal temperate and tropical waters. The cuttlefish has
an internal shell or bone, called the cuttlebone, that helps them to be buoyant.
Attached to this body structure is the head with eight arms and two feeding
tentacles. The cuttlefish can easily camouflage itself by changing its skin
color and pattern to blend in with its background. ThisRS. helps the
cuttlefish to hide from predators, and the sneak up on its prey. Like the squid
and octopus, the cuttlefish can eject ink in an effort to escape from predators.
This ink, called sepia, was once used as a dye to create ink used by artists.
The nautilus is native to deep ocean waters. It has a
multi-chambered shell. Each chamber is sealed and contains gas which provides
the nautilus with buoyancy to float. Like the octopus, squid and cuttlefish, the
nautilus uses jet propulsion to move forward. It sucks in water, then expels it
in a fast, strong stream to propel itself forward. The nautilus has as many as
90 small tentacles that it uses to catch food, such as shrimp, fish or small
crustaceans. It then uses its powerful beak to crush the food. The nautilus is
considered a living fossil because its form has remained unchanged for over 400
(VII) ECHINODERMS: STARFISH, SEAURCHIN AND FAMILY
Echinoderms are marine animals that live in the ocean. Common
echinoderms include the sea star, sea urchin, sand dollar and sea cucumber. Most
echinoderms have arms or spines that radiate from the center of their body. The
central body contains their organs, and their mouth for feeding. Sea stars,
commonly known as the starfish, have 5 or more arms attached to their body. On
the bottom of the Starfish are small tube feet to help with movement and
feeding. The starfish’s mouth is underneath, and is capable of eating other sea
life such as clams and mussels. Another type of echinoderm is the sea urchin.
Sea urchins have many spines connected to their body. These spines help to
protect them from predators.
The starfish or sea star is native to all of the world’s
oceans. There are about 1,800 different species of starfish with the greatest
variety living in the tropical Indo-Pacific region. Most starfish have five
arms, although some have fewer or more arms. Like other enchinoderms, starfish
have small tube feet on their underneath body to help with movement and feeding.
The starfish’s mouth is underneath, and it has two stomachs in the mouth. The
stomach sack can come out through the mouth to engulf and digest food, such as
clams and mussels.
Crustaceans are a type of Arthropod. The name may not sound
familiar, but you probably know them. You may even have eaten one. Crustaceans
live mostly in the ocean or other waters. Most commonly known crustaceans are
the crab, lobster and barnacle. Crustaceans have a hard, external shell which
protects their body. Crustaceans have a head and abdomen. The head has antennae
which are part of their sensory system. The abdomen includes the heart,
digestive system and reproductive system. The abdomen also has appendages, such
as legs, for crawling and swimming. Many crustaceans also have claws that help
with crawling and eating.
There are about 10,000 different species of crab.The crab is
native to all of the world’s oceans. There are also freshwater crabs, and even
some crabs that live on land. Crabs have a large, hard shell. Extending from the
front of its shell are the eyes, mouth and two pairs of antennae. The crab has 5
pairs of legs extending from the side of its shell. The first pair of legs have
claws or pincers used to catch and hold food. The other pairs of legs are used
for walking. Most crabs don’t swim, they use their legs to walk. However, some
crabs such as the Blue Crab can use their legs as paddles to swim.
Lobsters are native to most oceans of the world. The lobster
habitat is rocky, sandy or muddy ocean bottom and they are generally found
hiding in crevices or in burrows under rocks. Lobsters have five pairs of legs,
the first pair of legs are claws used to catch and hold food. Lobsters have a
large exoskeleton. As lobsters grow, the must molt to shed their old exoskeleton
as they grow a larger new shell.
Shrimp are native to many of the world’s oceans and lakes.
They are generally found in shallow water. Their habitat includes both fresh and
salt water. Although most shrimp are small, some can grow up to 9 inches in
length. The shrimp has a very simple body consisting of the head and thorax, and
a muscular abdomin for swimming. They have 8 pairs of legs, 5 for swimming and 3
for feeding. They also have 2 pairs of antennae use for taste and smell to find
food. As a crustacean, the shrimp has a thin, almost transparent, exoskeleton.
The shrimp is a popular food. In addition to commercial fishing for shrimp,
shrimp are also grown in shrimp farms. Shrimp are also commonly found in
(IX) ARACHNIDS: SPIDERS, TICKS AND SCORPIONS
Arachnids are a type of arthropod. You know many of them as
spiders. Common arachnids are spiders, scorpions, ticks and mites. Like other
arthropods, the arachnids have a hard exoskeleton and jointed appendages for
walking. Most arachnids have 4 pairs of legs. In some, the first pair of legs
may be used for holding their prey and feeding. Unlike other arthropods,
arachnids do not have antennae. Spiders are easily recognizedwith their 8
legs.All legs are used for walking. The first pair of legs is also used for
holding prey and feeding. The second pair of legs may also be used for holding
and killing their prey. Most spiders have 8 eyes. Spiders have fangs that are
used to inject poison to paralyze or kill their prey. Many spiders can produce
silkRS. hreads to spin webs for catching prey, and for building an egg sack
to hold and protect their eggs. Scorpions are large arachnids, some reaching
over 8 inches in length. They have 4 pairs of legs, and a pair of pincers for
catching and holding their prey. Scorpions also have a sharp stinger at the end
of their tail that is used to paralyze or kill insects and small animals.Mites
and ticks are small arachnids that are parasites living on the blood and tissue
fluid of other animals. They can occasionally transmit disease. The abdomen also
hasRS. appendages, such as legs, for crawling and swimming. Many crustaceans
also have claws that help with crawling and eating.
Scorpions are native to many parts of the world. There are
about 1,400 different species of scorpion. They prefer warm or hot climates, but
can even be found in cold, snowy areas. Their habitat includes deserts,
grasslands and savannahs, forests, intertidal zones, mountains and caves.
Scorpions are best known for their long, segmented tail with its venom-injecting
barb. The scorpionwill use its venomous stinger to capture prey and defend
against predators. Scorpions have four pairs of legs and a pair of pincer-like
pedipalps. These pincers can also be used to catch prey and defend against
predators. Scorpions are nocturnal animals. They prefer to find shelter during
the day in underground holes or under rocks where it is cool. They come out at
night to hunt and feed. Most scorpions prey on insects, spiders, centipedes, and
other scorpions. Large scorpions may also prey on small lizards, snakes and
Spiders are found world-wide on every continent except for
Antarctica. There are approximately 40,000 different species of spiders. Spiders
vary in size from quite small to relatively large. The Goliath Birdeater can
grow up to 10 inches measuring its leg span. Most people can easily recognize a
spider by its eight legs. One spider, the Daddy Long Legs, is even named after
its eight long legs. Another recognizable feature related to the spider is its
web. Spiders have spinneret glands they use to build webs. These webs provide
shelter and help catch food. Spiders also have fangs. Many spiders can inject a
venomous liquid through their fangs. Thisvenom is capable of paralyzing or
killing predators or prey. Some venom, such as from the Brown Recluse or Black
Widow, can even be dangerous or deadly to humans. Although some people are
scared of spiders,most spiders will only bite humans in self-defense. Fear of
spiders is called arachnophobia. Most spiders have four pairs of eyes. This
provides them with very good vision. Some spiders, such as the Tarantula, can be
very hairy.While many people are scared of the tarantula, this spider is
generally quite harmless. Some people even keep a tarantula as a pet.
The tarantula is a large, hairy spider found in tropical to
temperate regions of the southwestern United States, Mexico, Central America,
SouthAmerica, southern Europe, Asia, Africa and Australia. Tarantulas can go up
to 4 inches in body size, and have a leg span of up to 12 inches. Like other
arachnids, the tarantula has eight legs, arranged in four pairs. It also has
another pair of appendages used for feeling and gripping prey. The tarantula has
two fangs used to inject venominto its prey, or in defense against predators.
Tarantulas prefer to hunt at night. They will lay a web, but not to catch their
prey. They lay strands of web on the ground to act as a trip wire. When an
insect, frog, toad or mouse steps on the strand, alerting the tarantula, it will
pounce on the unsuspecting victim. Although many people find the tarantula
scary, it is generally harmless to humans. They will not bite unless provoked,
and if bitten the pain is usually similar to that of a bee sting. Some
tarantulas have even become a popular pet.
(d) Spider Web
Spiders can produce silken thread using spinneret glands on
their abdomen. This thread is very strong. It is stronger than a similar size
thread of steel. Spiders use this silken thread for many things. A spider will
spin a web to protect the entrance of their home from birds or wasps. A web is
also used to catch insects or other food. The thread is sticky, and once an
insect touches the web, it gets caught. Vibration of the web tells the spider an
insect has flown orRS. crawled into the web. The spider will then wrap its
prey in silken thread so it can’t escape. The thread is also be usedto attach an
egg sack to the web. This protects the eggs until the young are born. Sometimes
a web is used as a pathRS. between places where it is difficult to crawl.
There are many different shaped spider webs. Some spiders spin a circular web,
or orb web. Other webs look like funnels or tubes. Some webs look like a sheet.
Insects are the largest group of arthropods. There are over
800,000 different types of insects. Insects are very adaptable, living almost
everywhere in the world. Common insects include the fly, beetle, butterfly,
moth, dragonfly, bee, wasp and praying mantis. Insects have an exoskeleton that
covers their entire body. An insect’s body consists of 3 parts: the head, thorax
and abdomen. The insect’s head has a pair of antennae, and a pair of compound
eyes. Compound eyes are different from human eyes which have a single lens for
each eye. Compound eyes have many lenses for each eye. For example, the fly has
about 4,000 lenses in a single eye. This provides them with very good eyesight.
The thorax contains the legs for walking, swimming, jumping or digging. The
thorax may also have wings for flying. The abdomen contains many body organs,
such as the heart, respiratory system, digestive system and reproductive
system.The insect’s hard, exoskeleton makes it difficult for the insect to grow
and get larger. This is because the exoskeleton can’t grow and get larger. Many
insects must molt in order to grow. Molting is the process where an insect sheds
it outer skeleton. It wriggles out of this old skin, and a new, larger
exoskeleton develops. Invertebrates were the first animals to evolve.The first
invertebrates evolved from single-celled, food-eating
microorganisms.Invertebrates are often most noted for what they lack: a backbone
and a bony skeleton.Invertebrates account for 97 percent of all known
species.The simplest invertebrates, in fact the simplest animals, are
sponges.Most invertebrates change form as they grow, going through a process
known as metamorphosis.Some species of invertebrates form large
colonies.Invertebrates will eat almost anything thatRS. was or is alive.Many
of the world’s parasites are invertebrates. Vertebrates Animals with an internal
skeleton made of bone are called vertebrates. Vertebrates include fish,
amphibians, reptiles, birds, mammals, primates, rodents and marsupials. Although
vertebrates represent only a very small percentage of all animals, their size
andmobility often allow them to dominate their environment.
Almost three-forths of the world’s surface is covered in
water. This water is home to over 20,000 different species of fish. The earliest
fossils of fish date back over 400 million years. There are a wide variety of
fish — from the goby which is less than one half an inch long, to the whale
shark which can be over 60 feet long. Most fish breathe through gills. Gills
perform the gas exchange between the water and the fish’s blood. They allow the
fish to breathe oxygen in the water. Fishes areRS. ertebrates that have a
skeleton made of either bone or cartilage.About 95% of fishes have skeletons
made of bone. These bony fishes have a swim bladder, a gas- filled sac, that
they can inflate or deflate allowing them to float in the water even when not
swimming. Fishes with a cartilage skeleton tend to be heavier than water and
sink. They must swim to keep afloat. Cartilaginous (cartilage) fish include the
ray and the shark. Most fish swim using a tail fin. Muscles in the tail fin move
it from side to side, forcing water backward, andRS. propeling the fish
forward. Other fins help the fish change direction and stop. Pectoral fins on
their side help them swim up and down. Dorsal and anal fins on the top and
bottom keep the fish upright. Pelvic fins on the underside help steer left and
right.Many fish eat plants, while others such as the shark, eat other fish.
There are about 50 species of flying fish. They areRS.
found in all major oceans of the world, particularly in the warmtropical and
subtropical waters of theAtlantic, Pacific, and Indian oceans. As their name
implies, these fish can fly. They can’t fly as well as a bird, but they can take
shortRS. flights through the air. Most flying fish use their large pectoral
fins as wings. The fish can take short gliding flights above the surface of the
water in orderRS.RS. to escape from predators
There are two different species of paddlefish: the Chinese
paddlefish and the American paddlefish. The Chinese paddlefish lives in the
Yangtze River in China. The American paddlefish lives in the Mississippi,
Missouri, Des Moines, Yellowstone, Ohio and Oklahoma Rivers in the United
States. The most recognizable feature of the paddlefish is its large mouth and
long snout or bill. The spatula-like snout can be half the length of its body.
This is why the paddlefish is sometimes called the spoon fish
FACTS ABOUT FISH
Fish are divided into three basic groups which include
cartilaginous fish, bony fish, and lobe-finned fish. Fish were the first animals
to evolve backbones. The ray-finned fish are the largest group of fish.
Fish move by creating a wave motion that moves the length of its body.
Fish are cold-blooded (ectothermic) animals.
Many species of cichlids brood their eggs in their mouth.
After the eggs hatch the parent continues to use their mouth to provide shelter
for their young.
Cartilaginous fish include the sea’s largest and most skilled marine predators.
These include sharks, skates, rays, and chimeras.
These fish have skeletons made from cartilage, not bone.
The cartilaginous skeletons are more flexible than bone.
The lateral line system on some fish detects variations in water pressure.
This helps fish detect prey and avoid predators.
Amphibians lay their eggs in water, and young amphibians tend
to resemble small fish. The tadpole, or newborn frog, is born and lives in
water. It has a tail that allows it to swim like a fish. It also has gills so
that it can breathe under water. As the tadpoleRS. grow into a frog, it loses
its gills and tail, and develops legs for moving on land. Most amphibians can
both walk and swim in water. Depending on the species of amphibian, breathing
can take place in gills, lungs, the lining of the mouth, the skin, or some
combination of these. Amphibians body temperature changes with its environment.
In cold climates, amphibians hibernate during the winter.There are over 6,400
species of amphibians found worldwide, except in Antarctica and Greenland.
Amphibians are vertebrates and include animals such as frogs, toads,RS.
salamanders, newts and worm-like caecilians. They can be found on land, and in
fresh water. They live in a variety of habitats from deserts to rain forests,
permanent ponds orRS. high mountain meadows. Most amphibians have four limbs,
but some amphibians don’t have any limbs. Amphibians areRS. cold-blooded
meaning they use the environment to regulate their body temperature. Amphibians
spend part of their life in water, and part of their life on land.
(III) REPTILES: AFRICAN CLAWED FROG
The African Clawed Frog is native to South Africa, the
sub-Saharan in east and southern Africa, and Namibia and Angola in western
Africa. Their habitat includes warm stagnant pools and quiet streams. Their name
comes from the three short claws on each of its hind feet. It spends most of its
time underwater, only coming to the surface to breathe. African clawed frogs
don’t have tongues. The frog’s uses its front limbs and unwebbed fingers to push
food into its mouth.
(a) Poison Dart Frog
The poison dart frog is a family of frogs native to Central
and South America. Their habitat is humid, tropical areas such as tropical
rainforests. They may live on the ground as well as in trees. Most poison dart
frogs are brightly colored, which makes them easily recognizable and warns
potential predators to stay away. Why do the predators stay away? As their name
implies, this frog is highly poisonous. They secrete a toxin through their skin
that is capable of killing a predator. ManyRS. pecies are critically
RS.There are over 5,000 species of frogs. They are native
to most of the world, except Antarctica. Generally, we think of frogs as having
a short, stout body with long hind legs ideal for jumping. Most of us can
recognize a frog’s call as the familiar croaking or ribbit sound. Another common
characteristics is that frogs don’t have tails. The various species also have a
wide range of different characteristics. Some frogs are small, such as the Coqui.
Other frogs can be quite large. Some frogs are even poisonous, such as the
Poison Dart Frog.
Lizards, Snakes, and Others Reptiles have been around for 300
million years, even during the dinosaur age. The most common reptiles include
alligators, crocodiles, lizards, snakes, tortoises and turtles. Reptiles are
air-breathing animals, although many live not only on land but in water. The
most noticeable feature of reptiles are the scales that cover their body. The
majority of reptiles lay eggs to give birth to their young.Although reptiles
breathe through lungs, some reptiles can also absorb oxygen in water through
membranes in their mouth. Reptiles are often called cold-blooded because they
can’t regulate their own body temperature. Their body temperature depends on the
external temperature. They will lay in the sun to heat their body, or hide in
the ground, under a rock or in water to cool their body. Crocodiles and
alligators are large reptiles that spend much of their time on land and in
water. They can walk on land using their webbed feet. They can also use their
long tail to swimin water. Crocodiles feed on large animals they catch on land
or in water. They have powerful jaws and teeth to tear apart their prey.Lizards
and snakes are the largest group of reptiles. Lizards are four legged animals
with a long tail. Many lizards can shed their tail to escape from predators.
They can then grow a new tail.Some lizards, such as the chameleon, can change
colors to blend into their environment. This camouflage helps to protect them
from predators. Snakes don’t have limbs. They move by slithering along the
ground. Some snakes are poisonous, or venomous, such as the rattle snake, cobra,
and eastern green mamba. They have fangs which bite into their prey and inject
poison into the victim. Other snakes, such as the boa constrictor and the python
kill their prey by crushing it. Most snakes can dislocate their jaw, allowing
them to swallow prey much larger than themselves.
The alligator is native to the United States and China.
Alligators are covered with scales, head to toe. They can grow up to fifteen
feet long and weigh over one thousand pounds. Based on fossils, the alligator
has been on earth for 200 million years. They have a very strong jaw, capable of
crushing their prey. Alligators are cold-blooded. They lay eggs to produce their
(e) Anaconda Snake
The anaconda is a large, non-venomous snake native to
tropical SouthAmerica andNorthernAfrica. They mostly live in swampy or watery
areas. The green anaconda is the biggest snake in the world, with the largest
measuring up to 37.5 feet in length. The anaconda is related to the boa
constrictor snake. They kill their prey by constriction or squeezing. They wrap
themselves around their prey and squeeze to prevent the prey from breathing.
They then swallow the animal whole. (f) Chameleon The chameleon is a member of
the lizard family native to Africa, Madagascar, southern Europe, and Asia. There
are about 135 different species of chameleon. Their habitat includes rain
forest, savanna, semi-desert, and steppe land. Chameleons are best known for
their ability to change color. However, they don’t really change color to match
their surroundings, but based on mood, such as fear or anger, and based on
temperature and humidity. They are also known for their ability to move each eye
separately, and for their long, sticky tongue. Their eye can rotate 360 degrees
to view its prey, they its fast, sticky tongue can catch its prey.
(g) Cobra Snake
The cobra is a venomous snake native to Africa and Asia.
There are about 30 different species of cobra, with the King Cobra being the
world’s largest venomous snake. The cobra’s habitat ranges from tropical rain
forests and swamps to savannas and deserts. The name cobra is Portuguese for
“snake with hood.” Cobra’s are most famous for this hood, which is created by
elongated ribs that extend the loose skin of the neck behind the snake’s head.
Cobras will raise the front part of their bodies and display their hood when
threatened or disturbed. They will also make a hissing sound.
The crocodile is native to tropical areas inAfrica,Asia, the
Americas and Australia. The crocodile is an ancient, prehistoric creature,
believed to have inhabited earth for over 200 million years. The name crocodile
comes from an AncientGreekwordmeaning “lizard of the river.” Crocodiles prefer
freshwater habitats like rivers, lakes and wetlands. Crocodiles are similar to
alligators and caiman. They are veryfast over short distances, even out of
water. They catch their prey by waiting for fish or land animals to come close,
then rushing out to attack.
(i) Coral Snake
The coral snake is a venomous snake native to southern United
States includingArizona and fromLouisiana toNorth Carolina, including all of
Florida. Coral snakes are small in size, averaging 3 feet in length. They are a
very beautiful snake with their red, yellow/white, and black colored banding.
They are the second most venomous snake in the United States, behind the
The iguana is a family of lizards native to tropical areasRS.
of Central and SouthAmerica and the Caribbean. The green iguana, which is a
popular pet, lives in tropical rainforest areas near water, such as rivers or
streams. Other iguanas live in the dry, hot desert. Like other reptiles, the
iguana is cold blooded meaning they do not produce their own body heat. If an
iguana is cold, it will lie on warm rocks to soak up the sun’s heat. Green
iguanas are omnivorous meaning they eat both plants and meat, but they mostly
(j) Komodo Dragon
The komodo dragon is a lizard native to islands in Indonesia.
They are a member of the monitor lizard family. They are the largest of the
lizards, growing up to 10 feet in length and weight over 200 pounds. It is
carnivorous, eating animals such as pig and deer. It is also cannibalistic,
eating other komodo dragons. The komodo dragon has even been known to attack and
kill humans. They are now an endangered species.
There are over 5,000 different types of lizards in the world.
They are native to every continent, exceptAntarctica. Most lizards are small and
harmless to humans. But, the large Komodo Dragon has been known to attack and
kill humans. Lizards have some of the strangest characteristics. Some lizards
can walk onwater.Others can lose their tail to escape a predator. Others can
squirt blood from their eyes. The Chameleon can change colors to match its
surroundings. The Chinese Water Dragon can not only swim to escape predators,
but it can remain under water for up to 25 minutes. Some lizards are small, but
others such as the Monitor Lizard can grow up to 6 feet in length. Lizards such
as the Gila Monster are venomous. And, some lizards such as the Gecko and the
Iguana are common pets.
(l) Mamba Snake
The black mamba is native to Africa. Their habitat is open
grasslands, savannahs and woodlands. It is the largest venomous snake in Africa
and the second largest venomous snake in the world. They are considered the
deadliest snake in Africa. They are also considered fastest land snake in the
world, able to reach speeds of 12 miles per hour. Although they are called the
black mamba, they are generally gray, gray brown, or olive green in color. The
name black mamba comes from the black color inside their mouth.
(m) Viper Snake
The viper is a family of venomous snakes found all over the
world, except in Australia and Madagascar. Vipers range in size from the small
dwarf viper which is 10 inches in length, to the large bushmaster at 10 feet in
length. Vipers have a pair of fangs that are used to inject venomfromglands in
the rear of the upper jaws. These fangs are hinged, and when not in use fold
back against the roof of the mouth.
RS.Turtles are a reptile found in most parts of the world.
Some turtles live on land, while others live in the sea. They are easily
recognized by their shell. The turtle’s shell is covered with scales made
keratin, the same material as human fingernails. Many turtles can retract their
head and limbs into their shell for protection. The largest turtle, the
leatherback sea turtle, can have a shell length of 80 inches. Asmall turtlemay
be only 3 inches long. Turtles have a beak, not teeth. Female turtles lay eggs
to reproduce their young.
The tortoise is a reptile, closely related to the turtle. The
tortoise is often described as a land turtle. Turtles usually live in water and
have large blade-shaped flippers for swimming. Therefore, turtles find it hard
to walk on land. Whereas, the tortoise has legs rather than flippers and can
walk quiet well on land. Like the turtle, the tortoise has a large protective
shell. Tortoises can have longer life span that humans, sometimes living to be
over 150 years old.
(p) Sea Turtle
Sea turtles are native to all the world’s ocean, except the
Arctic Ocean. The largest sea turtles are seven feet in length and five feet in
width, weighing up to 1300 pounds. Some sea turtles are believed to live to be
80 to 100 years old. Sea turtles spend much of their time under water, but must
return to the surface to breathe air. All species of sea turtles are listed as
threatened or endangered.
(q) Sea Snake
Sea snakes are found in warm, tropical, coastal waters of the
Indian Ocean and Pacific Ocean. A few species are also found in Oceania. Sea
snakes are venomous snakes, and have fangs. Sea snakes are highly adapted to
living in the water. For example, they have a paddle-like tail for swimming.
Althought these snakes spend most of their time in the water, they must come to
the surface to breathe air
(r) Pitviper Snake
The pitviper is a family of venomous snakes found in Eastern
Europe,Asia and theAmericas. Their habitat ranges from desert to rainforests.
Pitvipers have a deep pit between the eye and the nostril on either side of the
head. This is an organ that detects heat from warm-blooded prey. Common
pitvipers include the bushmaster, copperhead and rattlesnake
(s) Python Snake
The python snake is native to Africa, Asia and Australia.
Burmese pythons were introduce to the Florida Everglades National Park in the
1990s. The python is one of the largest snakes in the world. The reticulated
python may grow to over 30 feet long and weight over 300 pounds. The python
generally feeds on small reptiles and mammals, but has been know to eat deer and
other large animals. The python kills its prey by constriction. It wraps itself,
or coils around its prey suffocating the animal by preventing it from breathing.
Rattlesnakes are venomous snakes native to North America and
a few other parts of the Northern Hemisphere. They get their name from the
rattle located at the tip of their tails that is used as a warning device when
threatened. The rattle is a set of rings on the tip of their tail. When
vibrated, the rattle creates a hissing sound that warns off predators.
Rattlesnakes use their venomous bite to catch and kill prey such as mice, rats,
small birds and other small animals.
FACTS ABOUT REPTILES
There are about 8,000 species of known reptiles alive today.
The first reptiles appeared approximately 340 million years ago during the
RS.Reptiles are cold-blooded. Reptiles have scales.
RS.The Mesozoic Era is the ‘Age of Reptiles’.
In many reptiles, the sex of the young is determined by the temperature the
embryos are exposed to during incubation.
Some of the largest reptiles alive today include
the leatherback turtle, the Komodo dragon, and
the saltwater crocodile.
There are over 8,000 species of birds. Birds have 3
major differentiating characteristics: wings for flight,
feathers, and a beak rather than teeth. Birds have adapted
their vertebrate skeleton for flight. Their bones and skull are
very thin, making their bodies extremely light. To support
flight also required other changes to their skeleton. Obvious
changes are the addition of wings. Other changes are less
obvious. The claws andmuscles of a bird’s foot are designed
to lock and hold onto a perch evenwhile the bird is sleeping.A
bird’s respiratory system is also adapted to make it easier to
breathe at high elevations, where air is thinner.
More information on birds
TheAlbatross is a large sea bird found near the Southern
Ocean andNorth Pacific. The albatross is among the largest
flying birds, and has the largest wing span. Its large wings
are excellent for flying, but can make taking off and landing
Swans are a family of birds native to many parts of
the world including the Americas, Europe, Asia, Africa and
Australia. Swans are the largest of the waterfowl compared
to ducks and geese. The largest swan in the world is the
trumpeter swan of North America whose wingspan can
reach 10 feet. The habitat of the swan is ponds, lakes, coastal
bays and rivers. They are easily recognized by their very
long necks which are often held in a graceful curve. Their
long necks allow them to feed underwater without diving
Vultures are native to the Americas, Africa, Asia, and
Europe. They are scavenging birds feeding mostly on
carrion, that is carcasses of dead animals. Vultures have a
good sense of smell, and can smell a dead animal from great
heights. One recognizable characteristic of many vultures
is their bald head with no feathers
(d) Ruby- Throated Hummingbird
The ruby-throated hummingbird is native to: the
Canadian prairies; eastern Canada, United States and Mexico;
Central America; and, parts of South America. Its habitat is
deciduous and pine forests and forest edges, orchards, and
gardens. The hummingbird has strong flight muscles and
blade-like wings allowing it to fly not only forward, but also
straight up and down, sideways, and backwards, and to
hover in front of flowers as it feeds on nectar and insects.
Parrots are native to most warm and tropical parts of
the world including Australia and the islands of the Pacific
Ocean, India, southeast Asia, southern regions of North
America, South America and Africa. There are about 372
different species of parrot. Parrots are one of the smartest
birds. Not only can they mimic human speech, studies have
shown they can associate words with their meanings and
form simple sentences
The ostrich is a large flightless bird native to Africa. It
is easily recognized by its long neck and legs. The ostrich is
a fast runner, capable of reaching speeds up to 45 miles per
hour. A large male ostrich can weight up to 350 pounds.
Matching its size, ostrich eggs are the largest of all eggs.
Penguins are a group of aquatic, flightless birds mostly living
in the Southern Hemisphere, particularly the Antarctica.
However, the Galapagos Penguin prefers a more temperate
climate living near the equator. Penguins are easily
recognizable by their black and white coloring, and their unusually upright,
waddling gait. The penguin looks like itRS.RS. s formally dressed in a
man’s tuxedo. These birds have adapted for life in the water. Their wings have
become flippers allowing them to swim fast in the water
Peacocks are large colorful pheasants. Although most people
know this bird by the name peacock, this name specifically refers to the male
bird. The female is called a peahen. Collectively they are referred to as
peafowl. There are three species of peafowl. The blue peacock lives in India and
Sri Lanka, the green peacock lives in Java and Myanmar, and the Congo peacock
lives in African rain forests. The peacock is best known for its known and
valued for its brilliant tail feathers. This iridescent blue-green or green
colored tail plumage, also called the train, has bright spots on it called
The kiwi is a flightless birds native to New Zealand. It is
an endangered species. They are an interesting looking bird with a plump body
and a long bill. Kiwi are shy and usually nocturnal. The kiwi is a national
symbol of New Zealand. They are so well known to the world, and representative
of New Zealand, that all New Zealanders are called “Kiwis”.
Hornbills are a family of birds native to tropical and
sub-tropical Africa and Asia. They can be found in open country as well as
forested areas. The most distinctive feature of the hornbill is their heavy
bill. It is long and down curved, and often brightly-colored. Hornbills are
omnivorous birds meaning they will eat fruit, insects and small animals. They
cannot swallow food from the tip of the beak because their tongue is too short.
They must toss it to the back of their throat.
(j) Great Blue Heron
The great blue heron is a large wading bird common over most
of North and Central America, as well as the West Indies and the Galapagos
Islands. They live near bodies of water such as fresh and saltwater marshes,
mangrove swamps, flooded meadows, lake edges, or shorelines. They build their
nest in trees or bushes near the water. They are often seen standing in shallow
water or at the water’s edge. They use their long legs to wade through the
water, and they spear fish or frogs with their long, sharp bill.
(k) Golden Eagle
The Golden Eagle is a large bird of prey living in North
American and other parts of the northern hemisphere. It is one of the best known
birds of prey in the Northern Hemisphere. It is powerful and strong with a
wingspan ofover 7 feet. The golden eagle’s eyesight is about 8 time smore
powerful than a human, and can spot prey from a long distance. Their talons are
well designed for killing and carrying their prey. They also have a powerful
beak for tearing into its food.
The flamingo can be found in many parts of the world
including Africa, Asia, North America, Central America, South America, and
Europe. They live near large, shallow lakes or lagoons. They are best know for
their pink color. They also have distinctive long legs and neck, and a curved,
pink bill colored black on the end.
The falcon is a species of raptor found on every continent,
except Antarctica. They live in a wide variety of habitats from tropics,
deserts, and maritime to the tundra. They have excellent vision allowing them to
see prey from high in the sky. Once spotting its prey, the falcon dives downRS.
after it. Falcons have thin tapered wings enabling them to fly at high speed and
to change direction rapidly. Peregrine Falcons can dive at speeds over 200 miles
per hour (322 km/hr), making them the fastest-moving animal on Earth.
FACTS ABOUT BIRDS
The earliest known bird, Archaeopteryx lithographical, lived about 150 million
years ago during the Jurassic Period.
Birds are not the only animals that are capable of flight.
Flight is not a characteristic restricted to birds.
Bats, which are mammals, fly with great agility and insects, which are
arthropods, were fluttering through the air several million years before birds
Birds do not have teeth.
The largest of all birds is the ostrich.
Mammals have several unique characteristics that
differentiate them from other animals. Most mammals have hair, or fur, covering
their body. They are also capable of regulating their body temperature. The
mammals metabolism controls heat production, and the sweat glands help cool the
body. These allow the mammal to maintain a constant body temperature, regardless
of the environmental temperature. One other difference is that mammals give
birth to fully formed babies, and the female mammals produce milk to feed their
young. Most mammals walk on 4 legs, with only the humans walking upright on 2
legs. Aquatic mammals have flippers, or fins, for swimming rather than legs.
Common mammals include: primates, such humans and monkeys; marsupials; rodents;
whales; dolphins; and, seals. (a) Marsupials Marsupials are best known for the
Australian members of the family, the kangaroo, wallaby and the koala. The only
marsupial native to North America is the Virginia opossum. There are also some
marsupials native to Central America and South America. Marsupials are members
of the mammal family. However, they are different from other mammals because
they have an abdominal pouch to carry their young. The marsupial female gives
birth very early and the baby animal climbs from the mother’s birth canal to her
pouch. Here the baby marsupial continues to develop for weeks, or even months,
depending on the species. At birth, marsupial babies are not fully developed.
The baby’s hind legs are just nubs. The baby lives and continues to develop in
the mother’s pouch. The pouch, or marsupium, also has the mother's mammary
glands for feeding the baby. AbabyRS. kangaroo may live in its mother’s pouch
for 6 months. Koalas and wombats are a little different from Kangaroos. The
kangaroo’s pouch is on the front, while the koala and wombat pouches are on the
The kangaroo is native to Australia. It is the largest of the
marsupials, and a national symbol of Australia. As a marsupial, the kangaroo
differs from other mammals in having a pouch on its stomach for carrying its
young. Early European explorers in Australia said the kangaroo had a head like a
deer (without antlers), stood upright like a man, and hopped like a frog.
Kangaroos have large, powerful hind legs, and large feet, well adapted for
jumping. They can hop along at 25 miles per hour, and are capable of reaching
speeds up to 45 miles per hour for short distances.
Humans are part of the primate family. Other common primates
include the monkey, baboon, orangutan, chimpanzee and gorilla. While humans
inhabit much of the world, most other primates live in tropical or subtropical
regions of the Americas, Africa and Asia. Primates have several distinctive
features that separate them from other mammals. Primates have well developed
hands and feet, with fingers and toes. Their opposable thumb makes it easy for
them to grab things. Primate eyes are forward in the head giving them
stereoscopic vision. This allows them to judge distance. Primates also have
large, highly developed brains. Their intelligence allows them to control and
manipulate their environment. The highly developed visual center of the brain
helps primates distinguish colors. Their large brain also allows them to develop
complex language and communication skills. Monkeys and apes walk on all four
limbs, but they may run upright using only their hind legs. Although primates
are born fully formed, they tend to have a long gestation period in their
mother’s womb. Parents also care for and educate their young much longer than
other animals. This results in a strong bond between a baby and the mother.
Primates are very social animals, and tend to form strong bonds with family and
friends. While humans are similar to monkeys in many ways, there are also
several significant differences. The human brain is more than twice the size of
other primates. This makes humans the most intelligent primate, with the most
developed communication, language and reasoning skills. Humans are able to make
and use complex tools to help control their environment. Humans also walk
upright on two legs. Although primates are born fully formed, they tend to have
a long gestation period in their mother’s womb.
(d) Rodents: Squirrels, Mice, Porcupines and Others
The largest family of mammals are the rodents. These mammals
are named rodent, which means “gnawing animal,” because of their large incisor
teeth and the way they eat. The two long pairs of incisors are used like chisels
to gnaw on hard foods like nuts and wood. These incisors must grow continuously
since they are worn down by gnawing. There are 3 major types of rodents,
represented by squirrels, mice and porcupines. Squirrel-like rodents such as the
squirrel and gopher, have bushy long tails and large eyes. They can live in
trees or underground in tunnels. They may hibernate during the winter.
Mouse-like rodents include the mouse, rat and hamster. Some have a long, thin
tail with short legs. Others have a short tail. They mostly live above ground,
although some burrow under ground. They may also hibernate during the winter.
Rats and mice often live near humans, sometimes in their buildings, so they can
live off human food and garbage. Porcupines differ from other mammals because
they have long, sharp quills on their backs for protection.
(e) Whales and Dolphins
Although they live in the water RS. whales, dolphins and
porpoises are mammals. Since whales and dolphins are mammals, they cannot
breathe under water. They must come to the surface to breathe air. They breathe
through a blowhole, or nostrils, on the top of their head. Babies are born under
water and must be pushed to the surface, bythe mother, so that they can take a
breath. Whales and dolphins also look different from many other mammals because
they don’t have fur. Although, they do have a sparse have adapted to living in
water. Whales and dolphins can dive deep in thewater on a single breath.Whales
and dolphins also have a highly developed brain. They are consider to be very
intelligent.Dolphins, and some whales, can use echolocation to find food and
identify objects around them. They make loud clicking and squeaking sounds that
bounce off objects and echo back to the dolphin. This echo tells the dolphin
about the nearby object.
The whale is a marine mammal found many ocean areas from
arctic and sub-arctic to warmer waters. Whales are best known for their size,
which can be up to 110 feet long. The Blue Whale is the largest known mammal to
ever live, up to 110 feet long and weighing 150 tons. The whale breathes air
into its lungs through a blowhole on the top if its head.
The Orca, also known as the Killer Whale, is the largest of
the dolphin family. It can be found in most of the world’s oceans. Orca’s have
very distinction coloring with a black back, white chest and sides, and a white
patch above and behind the eye. The orca is considered very intelligent and
trainable. The orca’s playfulness and sheer size make them a popular exhibit at
aquariums and aquatic theme parks.
Although dophins live in the water, they are a mammal. They
are related to the whale and porpoise. They breathe air through a blow hole on
the top of their head. They must routinely return to the surface for air.
Dolphins are very friendly to humans, and are considered to be very intelligent.
RS.(i) Seals, Seal Lions and Walrus
The seals are marine mammals. The seal family includes the
seal, sea lion and the walrus. Aseal’s respiratory systemis adapted for water.
Aseal can go for 40 minutes without a breath. This allows them to dive to a
depth of over 2,000 feet. Seals are well designed to swimin water. Their bodies
are very streamlined and their flippers propel them quickly through the water.
Seals also spend considerable time lying around on rocky islands and beaches.
But they are clumsy and move slowly on land using their flippers. Baby seals are
born on land after a long, 12 month gestation period. The pups develop rapidly,
with some able to swim within a few hours of birth. Walruses differ from seals
in that they are larger and have large tusks. They can be over 10 feet long and
over 3,000 pounds.
RS.Facts About Mammals
The first Mammals are tetra pods. Mammals have four limbs, a
characteristic that places them among the group of animals known as tetra pods.
It should be noted that although some mammals such as whales, dugongs, and
manatees have lost their hind limbs during the course of evolution, they are
tetrapods by descent. mammals appeared approximately 200 million years ago
during the Jurassic Period. Mammals are warm-blooded. All mammals have hair .The
Cenezoic Era is the ‘Age of Mammals’. The largest mammal is the blue whale.The
smallest mammal is the bumblebee bat.
Th Basics of Vertebrate Evolution
FROM JAWLESS FISH TO MAMMALS
Vertebrates are a well-known group of animals that includes
mammals, birds, reptiles, amphibians, and fish. The defining characteristic of
vertebrates is their backbone, an anatomical feature that first appeared in the
fossil record about 500 million years ago, during the Ordovician period.
Jawless Fish (Class Agnatha)
The first vertebrates were the jawless fish (Class Agnatha).
These fish-like animals had hard bony plates that covered their bodies and as
their name implies, they did not have jaws. Additionally, these early fish did
not have paired fins. The jawless fish are thought to have relied on filter
feeding to capture their food, and most likely would have sucked water and
debris from the seafloor into their mouth, releasing water and waste out of
their gills. The jawless fish that lived during theOrdovician period all went
extinct by the end of the Devonian period. Yet today there are some species of
fish that lack jaws (such as lampreys, and hagfish). These modern day jawless
fish are not direct survivors of the Class Agnatha but are instead distant
cousins of the cartilaginous fish.
Armored Fish (Class Placodermi)
The armored fish evolved during the Silurian period. Like
their predecessors, they too lacked jaw bones but possessed paired fins. The
armored fish diversified during the Devonian period but declined and fell into
extinction by the end of the Permian period.
Cartilaginous Fish (Class Chondrichthyes)
Cartilaginous fish, better known as sharks, skates, and rays
evolved during the Silurian period. Cartilaginous fish have skeletons composed
of cartilage, not bone. They also differ from other fish in that they lack swim
bladders and lungs.
Bony Fish (Class Osteichthyes)
RS.Members of the Class Osteichthyes first arose during
the late Silurian. The majority of modern fish belong to this group. Bony fish
diverged into two groups, one that evolved into modern fish, the other that
evolved into lungfish, lobefinned fish, and fleshy-finned fish. The fleshy
finned fish gave rise to the amphibians.
Amphibians (Class Amphibia)
Amphibians were the first vertebrates to venture out into
land. Early amphibians retained many fish-like characteristics but during the
Carboniferous period amphibians diversified. They retained close ties to water
though, producing fish-like eggs that lacked a hard protective coating and
requiring moist environments to keep their skin damp. Additionally, amphibians
underwent larval phases that were entirely aquatic and only the adult animals
were able to tackle land habitats.
Reptiles (Class Reptilia)
Reptiles arose during the Carboniferous period and quickly
took over as the dominant vertebrate of the land. Reptiles freed themselves from
aquatic habitats where amphibians had not. Reptiles developed hard-shelled eggs
that could be laid on dry land. They had dry skin made of scales that served as
protection and helped retain moisture. Reptiles developed larger andmore
powerful legs than those of amphibians. The placement of the reptilian legs
beneath the body (instead of at the side as in amphibians) enabled them greater
Birds (Class Aves)
Sometime during the early Jurassic, two groups of reptiles
gained the ability to fly and one of these groups later gave rise to the birds.
Birds developed a range of adaptations that enabled flight such as feathers,
hollow bones, and warm-bloodedness.
Mammals (Class Mammalia)
RS.Mammals, like birds, evolved froma reptilian ancestor.
Mammals developed a four- hambered heart, hair covering, andmost do not lay eggs
and instead give birth to live young (the exception is the monotremes).
Progression of Vertebrate Evolution
The following table shows the progression of vertebrate
evolution (organisms listed at the top of the table evolved earlier than those
lower in the table).RS.
RS. no jaws no paired fins RS. gave rise to
placoderms, cartilaginous and bony fish
RS .no jaws armored fish
RS. cartilage skeletons no swim bladder no lungs
RS. gills lungs swim bladder some developed fleshy
fins (gave rise to amphibians)
RS. first vertebrates to venture out onto land
remained quite tied to aquatic habitats external
RS. eggs had no amnion or shell moist skin
RS. scales hard shelled eggs stronger legs
positioned directly beneath body
RS. feathers hollow bones
RS. fur mammary glandswarmblooded