There is a very good chance that you (or your friend) have a forced perspective illusion photo somewhere in your collection. You know the ones: perhaps you’re holding up the leaning tower of Pisa or looming like a menacing giant about to eat someone else who seems unnaturally tiny.

By playing with the positioning and distancing of objects, these create an optical illusion where things appear bigger or smaller than reality—even though we know it’s not real.

As it turns out, humans are not the only ones enjoying this kind of visual trickery. Great bowerbirds (Chlamydera nuchalis) make these forced perspective illusions, too.

Read the full article at the Australian Academy of Science.