A polecat from Tiggywinkles, a special hospital for endangered wildlife, helps Royal Mail launch its Mammal stamps!
All the animals featured are looked after by special conservation projects due to changes in their environments. This hedgehog gives his stamp of approval!
Brown long-eared bats love to hang around in orchards and parks trying a spot a caterpillar for their lunch.
Dormice are found all across the UK but it isn't easy to see one. They can spend up to three quarters of their life asleep!
Humpback whales are famous for their singing. They sing songs to each other which can last up to 20 minutes.
The horseshoe bat population has gone down by 90 percent in the last 100 years, because of chemicals used by farmers.
Wildcats like this one are found in Scotland and experts reckon there are only 400 left in the wild.
Playful otters love to swim and slide on muddy banks and in the snow.
These sperm whales have BIG appetites. They can gobble up squid, octopus or even sharks.
The new stamps go on sale on 13th April 2010.