Humans are extremely good at identifying faces, even when they're tiny — and that fact could help police solve future crimes.
Researchers showed 32 participants high-resolution photo portraits of faces, and the participants were asked to identify people reflected in the subjects' pupils — often the photographer or someone standing next to the photographer.
When the reflected person was a familiar one, participants could identify him or her 84% of the time, the Los Angeles Times reports.
When the reflected figures weren't familiar, participants were still able to ID them 71% of the time based on comparisons to mugshots.
Such identification is an impressive feat: The portraits were some 12 million pixels, and the reflections in the pupils made up less than 0.5% of the face's area — about 54,000 pixels.
"The pupil of the eye is like a black mirror," says a researcher, per NDTV. "For crimes in which the victims are photographed (e.g. hostage taking, child sex abuse), reflections in the eyes of the photographic subject could help to identify perpetrators," write the authors of the British study in PLoS One.
Maybe that newly discovered extra layer in the cornea helps.
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