The claim: Eagles can see a rabbit from three kilometres, or read newsprint across a football field.
What the evidence says: Measured eagle acuity is about two to three times human — genuinely excellent, and among the best documented in vertebrates, but not the order-of-magnitude figures that circulate. The commonly repeated distances come from extrapolating laboratory acuity measurements far beyond what the studies tested.
Why it persists: 'Eagle-eyed' is a compliment before it is a measurement, and no one checks the number.
Where you'll meet it: Nature documentaries and trivia lists · Popular symbolism writing about 'eagle vision'
Sources (1)
- Peer reviewedReymond, Liseth (1985)Spatial visual acuity of the eagle Aquila audax: a behavioural, optical and anatomical investigationVision Research, vol. 25pp. 1477-1491Open source