Mammals
KNOWN SPECIES
6,615
0.28% of our world's living things are mammals
CHARACTERISTICS
- animals with a backbone (vertebrates)
- they produce milk for their young
- they have bodies covered with hair
SIZE RANGE
Less than 2.4 inches to more than 108 feet (6 centimeters to more than 33 meters)
WHERE THEY LIVE
- mainly on land
- some live in oceans and fresh water
Here are just SOME of the world’s mammals:

orca
SCIENTIFIC NAME:
Orcinus orca

caracal
SCIENTIFIC NAME:
Caracal caracal

reticulated giraffe
SCIENTIFIC NAME:
Giraffa reticulata

human
SCIENTIFIC NAME:
Homo sapiens

dog
SCIENTIFIC NAME:
Canis familiaris

giant panda
SCIENTIFIC NAME:
Ailuropoda melanoleuca

warthog
SCIENTIFIC NAME:
Phacochoerus africanus

green acouchi
SCIENTIFIC NAME:
Myoprocta acouchy

aye-aye
SCIENTIFIC NAME:
Daubentonia madagascariensis

Guess what?
Genetic studies have suggested that hippopotamuses are closely related to whales and dolphins.
Image Credits:
Aye-aye, M. Shanley/© AMNH; caracal, © Derek Keats/CC BY 2.0; dog, © Karen Taber; green acouchi, giant panda, reticulated giraffe, warthog, John White/© California Academy of Sciences; human, © Shutterstock; orca, © Sabine Templeton/CC BY-NC.