Bats have eyes. This –

is a direct observation. Biologists who study bats have tested the –
that bat eyes have adaptations for more efficiently capturing images under low-light conditions. Indeed, many bats have a high proportion of rod photoreceptors, which are associated with vision in low-light levels, in their retinas. The –
that living things like bats evolve adaptations, such as the high proportion of rods, can help explain many of the adaptations that bats and other organisms demonstrate.
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