Originally Posted by
Freya
Octopus have three hearts.
There are a few people who can see 4 ranges of colors (four cones in their eyes that can mix colors) compared to the normal 3. Tetrachromats. They are only known to be women, who are daughters of a color blind father. In fact they only have one confirmed case of this but believe there are more but they just don't realize they see more than others. Normally, with the three cones, you see about a million different colors. A Tetrachromat can see 99 million. (color blind see about 10,000)