Seeing Without Seeing: Inside the Iguana’s Mysterious Third Eye
On a bright afternoon in the tropics, a green iguana freezes mid-sunbath as a hawk sweeps overhead, ducking a split-second before danger becomes obvious. That lightning-fast flinch doesn’t come from ordinary eyesight but from a curious feature many reptiles carry like a rooftop sensor: a light-detecting organ perched between the eyes. Biologists call it the ...
