From Helen MacDonald, H Is For Hawk (Grove Press, 2015), a beautiful book, which I don’t want to finish:
The world she lives in is not mine. Life is faster for her; time runs slower. Her eyes can follow the wingbeats of a bee as easily as ours follow the wingbeats of a bird. What is she seeing? I wonder, and my brain does backflips trying to imagine it, because I can’t. I have three different receptor-sensitivities in my eyes: red, green and blue. Hawks, like other birds, have four. This hawk can see colours I cannot, right into the ultraviolet spectrum. She can see polarised light, too, watch thermals of warm air rise, roil, and spill into clouds, and trace, too, the magnetic lines of force that stretch across the earth. The light falling into her deep black pupils is registered with such frightening precision that she can see with fierce clarity things I can’t possibly resolve from the generalised blur. The claws on the toes of the house martins overhead. The veins on the wings of the white butterfly hunting its wavering course over the mustards at the end of the garden. I’m standing there, my sorry human eyes overwhelmed by light and detail, while the hawk watches everything with the greedy intensity of a child filling in a colouring book, scribbling joyously, blocking in colour, making the pages its own.