Why the salamander is at the heart of our vision

The tail of the salamander

In southern countries with large and varied populations of salamanders, children enjoy a rather cruel game. They cut of a salamanders tail or leg just for fun, and they watch as the salamander grows a new tail or leg. Worms and certain fish also have the ability to regenerate their own body parts.

Unfortunately, mammals do not have this privilege. However there is evidence that children can regenerate amputated fingertips. Biologists around the world have been fascinated by this phenomenon for decades. When a salamander loses a tail or a leg the muscle cells surrounding the traumatised area receive signals.

These cells – which are in a growth stage – will automatically take a step back and continue to develop as primitive, undifferentiated muscle cells.

The American orthopaedic surgeon and researcher in electrophysiology and medicine, Robert O. Becker, wrote a book in 1985 entitled ‘The Body Electric, Electromagnetism and the Foundation of Life.’

The first part of the book deals with regeneration, mainly in salamanders and frogs. Becker studied regeneration after amputation of body parts and hypothesised that electric fields play an important role in controlling the regeneration process. He mapped the electrical potentials on different parts of the body during regeneration, which showed that the central part of the body was normally positive and the other parts or limbs were negative.

When a body part of a salamander or frog was amputated, the voltage at the site of the amputation (measured relative to the central part of the body) changed from about -10mV (millivolts) to +20mV or more the next day, a phenomenon called injury current.

In a frog, the voltage would simply return to normal negative levels within four weeks and no limb regeneration would occur. In a salamander however, the voltage would change from +20mV to -30mV in the first two weeks, then normalise (to -10mV) over the next two weeks and the limb would regenerate.

Becker discovered that regeneration could be enhanced by applying electricity that respects the electrical properties of bone helps to promote regeneration and growth in the bone stress areas.

A good example of microcurrent!