Today we use modern technological magic such as celestial navigation, inertial navigation and satellite positioning navigation, and as a result are free to navigate anywhere in the universe. That is, if we have the means to transport ourselves, or our machinery to the desired location. We can chart the heavens, determine where we are and where we want to go, set a course and arrive within inches of the intended destination. It truly is incredible technology.

But there is something even more incredible. How do just hatched baby sea turtles embark on transoceanic swim of 8000 miles or so then return to the exact place they started? Baby loggerhead turtles are only a few inches long when they leave the shore in Florida. They are swiftly caught up in currents known as gyres (pronounced with a soft g as in jire) in the Atlantic. The gyre runs clockwise up along the U.S. coast, across the Atlantic then down to Spain and Africa before heading west, back towards Florida.

The gyre is rich in food and the water warm. Should the turtles lose their way into the cold waters they will quickly die. The mystery of their navigation capabilities was only guessed at until recently. Dr. Kenneth J. Lohmann and his wife, Dr. Catherine M.F. Lohmann at the University of North Carolina at Chapel Hill and former undergraduate, Susan Dodge, just issued a report on their latest research findings. They discovered that the turtles could “read” the earth’s magnetic fields to stay on course.

“To determine whether loggerhead hatchlings could distinguish among magnetic fields found in different parts of the gyre, the biologists fashioned tiny bathing suits for the animals that were tethered by a fishing line to a lightweight mechanical arm that swung in the direction the turtles swam. The creatures, which were later released unharmed into the ocean, did not notice that they weren’t making progress.”

A small fiberglass pool like tub was filled with seawater and fitted with computer controlled, electric wire coils that when energized created magnetic fields. When the coils created a field similar to that in the Atlantic off the coast of Florida, the turtles swam in a northerly direction as they would in the ocean. When the magnetic field was changed, as it would be off the coast of Africa they swam the other direction as they would when returning to Florida.

During previous research the Lohmanns had determined that the turtles were able to detect two specific features of magnetic fields: the angle of inclination and the magnetic intensity. The latest research shows conclusively that turtle hatchlings respond to these elements and use them to keep them on course in the warm currents. Changing the inclination and intensity changed the turtle’s course.

In the Pacific, along the coasts of Australia and Japan there are also colonies of loggerhead turtles that swim in another oceanic gyre. They navigate the ocean well although their navigation code must be different from the Atlantic species as the gyre takes a far different course across the earth. Is the map in the turtle’s genes? Would a Pacific loggerhead be able to find his way in the Atlantic gyre? The Lohmanns suspect not. "These results imply that turtles from different populations are not interchangeable," says Lohmann. "If one population goes extinct, we'll not be able to restore it by bringing in turtles from another part of the world."

Many other scientists are studying various animals and discovering more about the part of a brain that responds to magnetic stimuli. Called the superior colliculus, it contains neurons that appear to be able to process the magnetic field information, at least in the Zambian mole-rat. This animal is able to navigate quite well in the darkness of underground tunnels.

I will bet that sometime in the near future we will discover that we humans also have the ability to detect and use magnetic field information. Then all we will have to do is find out how to use it to navigate. Think of it … never being lost again. Always innately knowing that an unmarked road is the correct one, or a right turn, not a left will get you where you want to go. I know many married men would pay a lot of money for that ability. They would never again have to explain to their wives they don’t need to stop the car to ask for directions. They know the way just like turtles do.