Sea turtles reveal a sixth sense which acts as a "third eye" finding their way to home & to monitor changes in sunlight.

You might think that a turtle's shell is its snazziest feature, but their "third eye" is pretty darn incredible as well. In 2014, scientists published findings that addressed the pink spot that's located on the heads of leatherback sea turtles. The researchers discovered that in this area "the layers of bone and cartilage were remarkably thinner than in other areas of the skull," according to Science. "This thin region of the skull allows the passage of light through to an area of the brain, called the pineal gland, that acts as [a] biological clock, regulating night-day cycles and seasonal patterns of behavior." Therefore, the spot acts like a "skylight," which lets the turtles "sense the subtle changes in sunlight that accompany changing seasons, signaling them to return south when autumn approaches."