Assertion: auk's number | /r/HasProperty | 1,000,000 per square mm
Facets:
Source sentences:
text: This is due to the large number of photoreceptors in the retina (up to 1,000,000 per square mm in Buteo, compared to 200,000 in humans), a high number of nerves connecting these receptors to the brain, and an indented fovea, which magnifies the central portion of the visual field.