Animals With Backbones

MAMMAL

FISH

REPTILEBIRD

AMPHIBIAN

Animals with backbones are called vertebrates.

Vertebrates include many different kinds of animals. They can be found just about everywhere – in oceans, rivers, forests, mountains, and deserts.

Animals with backbones can be broken up into classes by characteristics.

They are:

Animals With Backbones

adapted from http://gideon.k12.mo.us/teachers/jswilley/htdocs/Classification%20of%20Animals.ppt

Bird CharacteristicsAll birds are classified in the class aves.Birds lay hard shelled eggs that hatch in their nest.There are about 9,000 types of birds.Birds are vertebrates that have wings and they are

covered with feathers. No other animal has this feature.

The bird’s skeleton is very light in weight. This helps them to fly. (Fossil evidence shows that birds may be a modern day relative of a dinosaur – the archaeopteryx. The archaeopteryx live over 160 million years ago, but had wings identical to modern day birds.)

Birds range in size from as small as your finger or as large as a human.

Birds, continued•Birds have beaks, but no teeth.•They are very social. One or both parents care for the helpless young.

Types of feathers:•Contour feathers – used for flight•Down feathers – used for warmth•Filoplumes – control movement of the contour feathers

Orders of BirdsOrders of birds:Perching :

tree dwellersperching foot has 3 toes pointing forward

and 1 toe backwardsEX: cardinal, robin, bluebird, and swallowsNon-perching land birds:

feed on seeds and fruit.prefer to walk rather than fly

EX: doves, pigeons, turkeys, and quail

Orders of BirdsWater Birds:Swimming birds –

round, broad, straining beakswebbed feetmigratory

Wading birds – long-leggedspearing types of beaks

Flightless Birds:have lost the ability to fly2 main groups – ostriches and penguins

Orders of BirdsBirds of Prey:

The most powerful group of birdsstrong hooked beakslarge feet with strong curving talons2 toes face forward and 2 toes face

backwards2 groups –

diurnal – hunt by daynocturnal – hunt by night

Reptile CharacteristicsClass: Reptilia which means “creepers”Dinosaurs were giant reptiles and

although they are extinct now, 4 of the 16 major groups of these giant reptiles have relatives today:Snakes and lizardsTurtles and tortoisesCrocodiles and alligatorstuataras

There are over 6,500 species

Reptile Characteristics•Bony skeleton•Ectothermic•Thick, dry, waterproof skin•Use lungs to breathe oxygen•Have a 3 or 4 chambered heart, allowing them to provide more oxygen to their body•Amniotic egg – eggs have a leathery shell and a yolk to feed the embryo developing inside the egg•Most, except snakes, have two sets of small legs

Snakes and LizardsBoth:The largest and most varied group of reptilesLive on every continent except AntarcticaDo not have moveable eyelids or external earsHave teeth that grow out of their jawbone, similar scales, and smell by flicking tonguesLizards:Use tails to wrap around branches and can break them off to escape predators – they grow back.Snakes:“hear” by detecting movement in the ground

Crocodiles and AlligatorsBoth:•Sharp teeth•Heavy bodies•Long snouts•Large muscular tailsCrocodiles have a narrow head with a triangular shaped snout. They are more aggressive than alligators. They have been known to attack animals as large as cattle.Alligators have a rounded snout and are one of the few reptiles that care for their young. Feed on fish, turtles, and water birds.

Turtles and Tortoises•Move very slowly•The shell is made up of plates of bone connected to theribs and backbone• No teeth, but very powerful jaws•Do not protect their young•Turtles live in water and have thin, light shells that help them swim•Tortoises live entirely on land and have thick, domeShaped shells

Tuataras – “living fossils”•Oldest and smallest group of reptilesare the last surviving species of the primitive reptiles of •The past• They live on isolated islands off the coast of NewZealand•There are strict laws protecting their habitats

Amphibian CharacteristicsClass: Amphibia which means “double life”They live part of their life in water and part

on land.Tadpoles have gills and live in water. Adults

form lungs and may live on land.Most go through metamorphosis which

means they go through multiple stages of development.

Most have moist skins (not toads) and are sticky to the touch because of a mucus they make.

Must return to water to mate and lay eggs.Divided into 3 orders based on body

structure: Frogs and toadsSalamanders, sirens, and newtsThe odd caecilians

Amphibian Characteristics

•Like fish, they are bioindicators.•Ectotherms:

in cold weather, they become less active and bury themselves in mud or leaves until it becomes warm (hibernation)

those that live in hot, dry climates hide in the ground when it is too hot (estivation)•They may be adapted for life on land, they MUST have water for their skin and reproduction

Frogs and ToadsThe most abundant amphibiansMay live on land, in water, or treesLive in diverse habitatsBulging eyesNostrils on top of their headFrogs:

more slender, active, smooth skin, long hind legs, and fully webbed feetToads:

fuller-bodied, less active, prefer land, dry bumpyskin, shorter legs, and little webbing on feet

Salamanders and Newts•Long bodies•Long tails•Two pairs of short legs•Live on land and water•Feed on worms, crustaceans, and insects•Most live in North America

salamander

newt

Caecilians (little-known amphibians)•Long-bodied without limbs•Almost tailless•Smallest order of amphibians•Live in tropics and are very common in parts of Africa,•Asia, and Central and South America

Ringed caecilian (Siphonops paulensis)

Ichthyophis glutinosus

Fish CharacteristicsThey are the largest group of vertebrates.Many fish are covered with scales that

protects them. Their scales grow with the fish. You can calculate the age of a fish by counting the growth rings that form as the scale expands.

They have fins that help them to steer and balance in the water.

Most fish float with the help of a special feature called a swim bladder.

Their body temperatures vary in the water.They breathe through gills.

adapted from http://gideon.k12.mo.us/teachers/jswilley/htdocs/Classification%20of%20Animals.ppt

BioindicatorsA bioindicator is an organism whose health

reflects the health of the ecosystem. If the water is healthy, then there are plenty of healthy fish. So, if a source of water has lots of ill fish or is lacking fish altogether, that is an indication that there is something wrong with the water.

Fish are a very important animal to man. Many people around the world depend on fish as their primary source of protein.

Class Agnatha – jawless fish• Scavengers and parasites.• Oldest and simplest of the vertebrates.• Round sucker shaped mouths and long tube-

like bodies covered with slimy, scale-less skin.• Lampreys and hagfish are the only two

jawless fish.

Class Chondrichthyes – cartilaginous fishSkeletons made of cartilageHinged, moveable jaws with an endless

supply of teethCovered with tiny scales that feel like

sandpaperSharks, skates, and rays

Class Osteichthyes – Bony fishThe most numerous and varied of all the fishSkeletons made of bone and cartilageHave the lateral line system and swim bladder3 groups: lungfish, lobe-finned, ray-finned

adapted from http://gideon.k12.mo.us/teachers/jswilley/htdocs/Classification%20of%20Animals.ppt

Mammal CharacteristicsHave hair on their bodies at some point in

their lives. Whiskers count as hair.Endothermic – warm-bloodedFemales produce milk to feed their youngMost mammals give live birth to their

offspring. More complex brain than other animals.Their teeth and digestive tracts are

specialized to suit them depending on what they eat.

Monotremes-Egg laying mammalsMake up the smallest group of mammalsLay eggs with a leathery shellLive in AustraliaBest known – duck-billed platypusSpiny ant-eater is the only other

monotreme

Marsupials – Pouched mammals2nd largest group of mammalsLive in Australia or adjoining islands – with

one exception….the opossumGives birth to a tiny immature offspring that

must complete development in its mother’s pouch

EX: Koala bear, kangaroo

Placental mammals95 % of mammals fall into this categoryThe embryo stays inside the female’s body

until it is fully formedGestation (the time an embryo takes to

develop) can range from 16 days such as hamsters up to 650 days for elephants