Rhinosaurus are big, tough-skinned animals of Africa and Asia. African black and white rhinos and the smaller Sumatran rhino have two horns in the middle of their heads: Indian lindiavan rhinos have just one.
Powdered rhino horn is believed by some to be a love potion, so thousands of rhinos have been slaughtered and most kinds are now an endangered.
Baluchitherium lived 20 million years ago and was a type of the rhino. At over 5 m tall, it was much bigger than any elephant.
Hippopotamuses are big, grey, pig-like creatures that live in Africa. They have the biggest mouth of any land animal.
When a hippo yawns, its mouth gapes wide enough to swallow a sheep whole, but it only eats grass.
Hippos spend their days wallowing in rivers and swamps, and only come out at night to feed.
A hippo’s eyes, ears and nose are all on the top of its head, and so remain above the water when the rest of its body is completely submerged.
The word hippopotamus comes from the Ancient Greek words for horse (hippo) and river (potamos).
The African white rhinoceros’s horn can grow to over 1.5 m long.
The pygmy hippo is only about 90 cm tall but it is just as tubby as its big cousin and weighs up to 250 kg.