VERTEBRATES
FISH
RESPIRATION
Gills
REPRODUCTION
Oviparous
BODIES
Have a long body covered with scales
EXTREMITIES
Fins
BIRDS
RESPIRATION
Lungs
REPRODUCTION
Oviparous
BODIES
Their bones are thin and light, with lots of air spaces inside
EXTREMITIES
Two legs and two wings
AMPHIBIANS
RESPIRATION
Gills when amphibians are young
Lungs when amphibians became adults
REPRODUCTION
Oviparous
BODIES
Thin and smooth skin
EXTREMITIES
Four legs
Many amphibians have a tail
MAMMALS
RESPIRATION
Lungs
REPRODUCTION
Viviparous
BODIES
Skin and hair cover their bodies
In some mammals the hair is thick and called fur
EXTREMITIES
Most terrestrial mammals have four legs and a tail
Human beings have two legs and two arms
Aquatic mammals have fins (whales and dolphins)
REPTILES
RESPIRATION
Lungs
REPRODUCTION
Oviparous
BODIES
Reptiles have hard scales
Some reptiles have a hard shell (turtles)
EXTREMITIES
Many reptiles have four legs
Snakes don´t have legs