It has been shown that if you scare or threaten a Horned Toad it actually squirts blood from its own eyes to attempt to protect itself and distract his predator! But don’t feel bad for the toad, it doesn’t hurt him at all, it just gives him time so he can hop away.

[more info]

The vision of a hawk is many times sharper than that of a human being. Their retinas contain approximately 1 million photoreceptors per square millimeter and a human retina contains about 200,000 in the same amount of space. Every photoreceptor has a nerve connecting it to the hawk’s brain. Additionally, their eyes have special magnification properties. This is why hawks, as birds of prey, are able to see small animals from great heights.

[wikipedia]

“Scientists have actually studied how the way we feel about the things we see affects the size of our pupils (welcome to the world of pupilometrics). You can gain some insight as to how someone feels about you (or someone or something else) by observing changes in their pupils, and you can also affect the way someone feels about you by changing the size of your pupils!”

[wikihow] How to change the size of your pupils
[pupilometrics]

“The body of the Octopus, or Two-spot Octopus, is covered with chromatophores that allow it to blend in with any background by changing color. The name “Two-spot” comes from the conspicuous spots below each eye. Unlike most animals, the Octopus has a rectangular pupil. It usually comes out at night to feed on small invertebrates or sleeping fish. It uses its eight tentacles to bring the catch to its beak-like mouth.”
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“Dolphins have a superior eyesight, whether they are in or out of the water, and their hearing is also far superior to that of a human.”
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“The genetic trait for Blue Eyes is recessive. Two blue eyed parents cannot have anything other than blue eyed children. If two true blue eyed parents have a child with eyes colored anything but blue chances are the child is adopted.”
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