Five of the smartest animals in the world

This shouldn't come as a surprise - the intellectual might of chimpanzees has been fascinating humans since long.

And why not? Chimps are capable of making and using their own tools, hunting in organized groups, and even engaging in complex problem-solving.

Moreover, they are pretty good at learning and communicating via sign language.

They are also known to form strong social groups and bonds.

Elephants boast of a great memory.

In fact, once, two circus elephants rejoiced after reuniting as many as 23 years later.

And their intelligence isn't merely limited to memory, elephants are quite self-aware. They can recognize themselves in mirrors.

Also, they are known to be quite emotional. After humans, they are the only animals who mourn their dead, perform burial rituals and visit graves.

You may not find crows to be the most delightful of fellows, but you sure can't deny that they have got some brains.

They are known to craft their own tools from twigs, feathers and other bits of debris to pick out food from difficult places.

What's more? Crows also communicate in elaborate dialects and even play games and tricks on each other.

Move over their cute antics - dolphins have got some smarts to show.

Not only do they have an impressive brain-to-body size ratio, they are evidently capable of showing emotion, and of course mimicking their human friends.

Furthermore, studies have shown that dolphins can be deceptive. In one particular study, a dolphin tricked researchers in order to maximize her food reward. Clever beings!

Pigs have got a bad rap for being unhygienic - but the fact is that they are one of the cleanest domestic animals around.

Plus, they happen to be highly intelligent. Apparently, pigs understand emotions, display empathy, learn simple symbolic languages, solve mazes, among other things.

Studies have shown that they could be as smart as baby humans.