Has a Caltech Scientist Discovered a Sixth Sense in Humans?

Caltech scientist and Pasadena resident Professor Joseph L. Kirschvink believes he has discovered a magnetic sixth sense in humans.

Having conducted research on what is termed as magnetoreception – a sense of Earth’s magnetic field – for many years, Kirschvink is now testing humans’ magnetic sixth sense after studies that showed animals, even microorganisms, follow a magnetic sense of direction.

Two floors underground at Caltech, Kirschvink is conducting experiments to detect the human magnetic sense – with his students and himself as subjects.

The experiments are inspired by earlier discoveries of animal magnetism, first discovered by chance around 1957 when Hans Fromme, a researcher at the Frankfurt Zoological Institute in Germany, saw how robins kept in a cage were becoming restless and were fluttering into the southwestern side of the cage – even when the cage was in a shuttered room and the birds couldn’t see anything outside. Fromme then deduced they were acting on something invisible, and it must be the Earth’s magnetic field.

Even at that time, the field of magnetoreception wasn’t given serious consideration, until 1975 when Richard Blakemore discovered bacteria containing chains of magnetite crystals encapsulated in organic membranes. Blakemore realized that these chains of crystals were the reason why bacteria are able to swim in straight lines, allowing them to cover more new territory in their search for food.

Since that discovery, magnetotactic, or magnet-containing microbes have been found in oceans and freshwater lakes throughout the world. Later on, many higher animals were shown to be using the Earth’s magnetic field in navigation.

The theory of magnetoreception has also been invoked many times as scientists study animal migration, leading them to believe that migratory animals – from birds to yellow fin tuna, leatherback turtles to large whales – do follow a certain route corresponding to the Earth’s magnetic field when they move from one hemisphere to the other, even when they travel much of the time in darkness in the open sea, with no visible landmarks or even underwater channels to guide them.

Kirschvink and his team at Caltech is now in the process of finding out if magnetoreception is present in humans. In a clean room with magnetically shielded walls, the maverick scientist would strap EEG (electroencephalogram) sensors onto his own head, or his students’, and attempt to measure his response to custom magnetic fields generated by an array of electrical coils.

Scientists already know that animals can sense the Earth’s magnetic field. The main objective of Kirschvink’s experiments is to see how the human brain actually uses this information about the magnetic field at the cellular and neural level. They would like to see which part of the brain – or of the whole human body – actually receive these magnetic field signals – the magnetoreceptors – and process them to give humans a sense of direction.

Kirschvink specializes in measuring remanent magnetic fields in rock, which can indicate the latitude at which the rock formed, millions or billions of years ago, and can trace its tectonic wanderings. As an originator of scientifically plausible hypotheses, Prof. Kirschvink, who got his BS and MS at Caltech and his PhD from Princeton University, has originated several such ideas aimed at increasing understanding of how biological evolution has influenced, and has been influenced by, major events on the surface of the Earth.

His major contributions include the idea that biogenic magnetite produced by the magnetotactic bacteria, or “magnetofossils,” might be responsible for the magnetization of some sedimentary rocks; these magnetofossils now provide the strongest evidence for early life on the planet Mars.

Another major idea is that the magnetic field sensitivity in animals might be due to small chains of the same biogenic magnetite functioning as specialized sensory organelles; this work has provided a solid biophysical basis for understanding magnetic effects on animal behavior, and has actually led to the discovery of these new sensory organs in higher animals.

An idea that is generating much interest recently is that the entire Earth may have actually frozen over several times in Earth history, resembling a “Snowball”, potentially causing some of the most severe crises is history of life on Earth and perhaps stimulating evolution.

Another original concept from Kirschvink is that the Cambrian Evolutionary explosion may have been precipitated in part by large burst of true polar wander, in which the Earth’s rotational axis moved to the equator in a geologically short interval to of time, and that the burst of biomineralization observed in the fossil record at the Cambrian Explosion may have resulted from the evolutionary exaptation of the magnetite biomineralization system.

The Kirschvink group at Caltech maintains laboratories dedicated to the study of weakly magnetic biological and geological materials.

Prof. Kirschvink delivered the Carl Sagan Memorial Lecture at the 2001 American Geophysical Union Fall meeting in San Francisco.

Kirschvink won the Richard P. Feynman Prize for teaching excellence at Caltech, and the William Gilbert Award from the American Geophysical Union. He resides alternately in Pasadena and Osaka with wife Atsuko Kobayashi, herself a neurobiological electron microscopist at Caltech, and children Jiseki and Koseki, whose names mean “magnetite” and “gemstone,” respectively, in Japanese.