The New York Times offers an analysis of cute and a helpful infographic

Sales of petite, willfully cute cars like the Toyota Prius and the Mini Cooper soared, while those of noncute sport utility vehicles tanked.
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King Kong’s newly reissued face has a squashed baby-doll appeal, and his passion for Naomi Watts ultimately feels like a serious case of puppy love – hopeless, heartbreaking, cute.

Scientists who study the evolution of visual signaling have identified a wide and still expanding assortment of features and behaviors that make something look cute: bright forward-facing eyes set low on a big round face, a pair of big round ears, floppy limbs and a side-to-side, teeter-totter gait, among many others.