26. Built-in-goggles

Sea birds such as gulls, Skuas and terns have built-in-goggles.

The retina of these birds contain a minute droplet of a reddish oil.

It has the same effect as a red translucent plastic sheet held in front of the eyes.

The red drop absorbs the blue glare from the sea and the sky before the light reaches the retina.

Nature’s free gift of red-tinted, built-in-goggles for these lucky birds!