People have been speculating about the Mona Lisa for more than 500 years.  Who was the model?  Why did da Vinci paint her?  Is there a subliminal or deeper meaning?

Now, a 37 year old artist has found "hidden" images on the Mona Lisa which he believes might crack the code.

Ron Piccirillo found the heads of a lion, an ape and a buffalo hovering in the air after turning the painting on its side.

He also discovered a crocodile or snake coming out of the left hand side of her body by following the instructions as laid out in the journals of Leonardo da Vinci, who painted the picture.

Mr Piccirillo claims that his discovery cracks open the meaning of the work - that the Mona Lisa is actually a representation of envy.

To find the items, all Piccirillo had to do was turn the painting on it's side.

Mr Piccirillo, 37, who is an oil painter and graphic designer, said made his discovery after "employing an old artist's trick" of turning the Mona Lisa on its side to get a fresh perspective on the painting.

It was at that point that he noticed the lion's head hovering in the air above the Mona Lisa's head.

He said: "Then I noticed the buffalo and I thought: 'Oh my god'.

"Then I realised I was really onto something.

"I just could not believe what I was looking at. I realised: 'This is what I've been looking for'.

"I spent the next two months pouring over da Vinci's journals and came across the passage on envy which for me sums up what this is about.

"The Mona Lisa is a depiction of envy.