Pigeons are known for the ability to fly home from huge distances, but most people don't know that they do this with the aid of a photographic memory.

The Unlimited's Kevin Rolfe explains that pigeons actually recognise every building and landmark within about a 57km radius of their home base.
"So if they're flying in bad conditions, like today, that simply fly lower and navigate by means of landmarks," he says.
Winston the pigeon today flew 80km to deliver a flash drive loaded with 4Gb of data from The Unlimited's Howick call centre to its head office in Hillcrest, covering the distance in just over one hour.
Rolfe points out that this distance is just a training run for a trained homing pigeon and that the 11-month-old Winston regularly covers much greater distances when racing.
Pigeons have incredibly sharp eyesight, he adds, and are often used for sea rescue. They can cover huge distances over the ocean and, as soon as they spot the telltale orange colour of a lifeboat, peck a button they are carrying to send the co-ordinates back to rescue craft.
These little-appreciated birds are also valuable employees in the pharmaceutical field, where they are able to spot defective tablets on the production line.
When Winston made his data-carrying flight this morning, he was released from Howick together with a number of other pigeons, which formed a flock to fly home. Winston, however – as a professional racing bird, arrived home first, followed about 18 minutes later by the rest of the flock.