You can identify birds, also known as Aves or avian dinosaurs, by their beaked jaws that lack teeth, their ability to lay hard-shelled eggs, their speedy metabolism and a lightweight skeleton. While most fly, many cannot, in part due to their vast size disparity: the smallest bird, the bee hummingbird, measures just two inches long, while the largest, the ostrich, measures up to nine feet.
What if, in addition to wings, though, they had arms? Would you still be able to discern a bluejay from a Florida scrub? A puffin from a penguin? Would they look less like an egg-laying vertebrate and more like your neighbor wearing a disguise?
Some of the birds featured in the following quiz are weird enough as they are, boasting bright turquoise claws, painting their own feathers with clay or sleeping with one eye open. What if we added some arms to the mix?
Since wings originally evolved from forelimbs, a couple of extra limbs wouldn't be a totally random addition. The extinct moa bird, after all, had no wings. Perhaps these arms will let you imagine a different time, when birds belonged to a group of theropod dinosaurs in the Mesozoic Era. Or maybe you'll get distracted by imagining how weird it would be if birds had arms today.
Regardless, let's see how much bird species knowledge you're truly armed with!