Humans May Have a Residual Magnetic Sense
Could our ancestors have navigated by Earth’s magnetic field? Some scientists believe they have evidence.
Japanese scientists have replicated experiments with human subjects first tried at Caltech. According to Science Daily, they believe they have found evidence for an ancient magnetic sense in humans.
Many animals, such as migratory birds and sea turtles, have a geomagnetic sense that supports their biological navigation system. Although magnetoreception has been well-studied in these animals, scientists have not yet been able to determine whether humans share this ability.
The experiments showed that human brain waves can respond to changes in magnetic fields manipulated by researchers in controlled conditions.
Geoscientist Joseph Kirschvink, neuroscientist Shin Shimojo, and their colleagues at Caltech and the University of Tokyo set out to address this long-standing question using electroencephalography to record adult participants’ brain activity during magnetic field manipulations. Carefully controlled experiments revealed a decrease in alpha-band brain activity — an established response to sensory input — in some participants. The researchers replicated this effect in participants who responded strongly and confirmed these responses were tuned to the magnetic field of the Northern Hemisphere, where the study was conducted.
Each magnetic field line intersects the land with a specific intensity and inclination. These two factors create a grid that permit some animals to navigate in the dark or underwater, where other cues may be unavailable. The article does not say whether this ability could be restored in humans through training.
The ability for humans to navigate by the earth’s magnetic field, if proved, would presuppose sophisticated hardware and software built into our bodies and brains. If you watched Illustra’s film Living Waters, you marveled at how salmon and sea turtles use this ability to navigate across oceans. Sea turtles store a mental map of magnetic waypoints along their route. They can retrace their route decades later to arrive at the very beach where they were hatched as babies. That is truly incredible! Even little monarch butterflies may use magnetism as a cue as they fly thousands of miles to their birthplace. How did this ability arise in fish, reptiles, insects and mammals? Is that a case of Convergent Stuff Happens? It’s ridiculous to think so.
The brief article ends, “Future studies of magnetoreception in diverse human populations may provide new clues into the evolution and individual variation of this ancient sensory system.” Why must evolution always be brought into any discussion of a highly-effective trait? If this is “evolution,” it’s more like devolution. It represents a capability that our ancestors had that we have lost, possibly through mutation. See Michael Behe’s new book Darwin Devolves for details about how whatever evolution occurs, even if it helps an organism in a particular situation, comes about by breaking or blunting pre-existing genetic information. It’s much easier to lose an ability that to gain it by the Stuff Happens Law.