Clever optical illusion posters will make you double take

Negative space might not sound that exciting, but when used creatively, it can become so much more than just, you know, emptiness. As shown by these brilliantly creative posters from an animal shelter, sometimes negative space can even take on a life of its own.

The posters, created for World for All in Mumbai, each contain two images in one. The image is framed by people enjoying a special moment (such as an embrace, or gazing lovingly at a baby), while the empty space between them creates the shape of an animal. Check out our favourite print ads for more ingeniously creative examples.

Created by McCann Worldgroup India, the clever print ads contain the slogan 'There's always room for more. Adopt.' And it would appear they were successful, with World For All telling The Dodo that attendance at its annual adoption event rose by over 150% over the previous year after the publication of the ads. 

The ads were also popular on Reddit. "I didn't realise good ads like this exist!" one user exclaims, "Very wholesome." However, some did wonder whether the ads could be misinterpreted – with the animals seen as coming between these people and their special moments. Not that McCann will mind – World for All's Behance page reels off a list of awards won by the ads. 

Not all optical illusion ads we've seen are as wholesome as this (we recently filed McDonald's' kissing burgers under 'wish we could unsee'). But don't worry – there's plenty to feel positive about in our list of the best examples of negative space. 

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