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Bioelectromagnetism

Magnetic bacteria are anaerobic and their movement is toward the bottom, where conditions are

most anaerobic, as directed by geomagnetic feld. Te magnetic force lines of the geomagnetic feld

are horizontal near the equator. However, as the North and South Magnetic Poles are approached,

the vertical components become larger, and magnetic dip, the downward slant toward the earth’s sur­

face, increases. If the magnetic force lines are followed, northward in the Northern Hemisphere and

southward in the Southern Hemisphere, it is possible to move in a controlled direction within the low-

oxygen environment of sediments. Interestingly, the discovery history of magnetotactic bacteria was

introduced (Frankel, 2009). Tere are two unpublished manuscripts dated 1963 reported on “magneto-

sensitivity” in aquatic bacteria. Te original papers were written in Italian. Te English translations of

two manuscripts have been submitted for publications (Bellini, 2009a, b). In Bellini’s manuscripts, he

observed that bacteria oriented evidently themselves in a unique direction, and these microorganisms

moved to the direction of the North Magnetic Pole, which he called “magnetosensitive bacteria.” On

the basis of these observations, he hypothesized that: (1) the bacteria contain an initial, biomagnetic

dipole, (2) the magnetic dipole caused cells to migrate downward in the Northern Hemisphere toward

the less oxygenated bottom sediments, (3) magnetosensitive bacteria in the Southern Hemisphere

should swim toward the South Magnetic Pole, and (4) the biomagnetic dipole was fashioned from iron

compounds (Frankel, 2009). Frankel mentioned, Te experimental observations presented by Bellini

in the two manuscripts correspond very well with the observations of Blakemore and others and Bellini

did make a valid, frst discovery and present hypotheses that were later verifed. Te fnding of Bellini

remained obscure until the Blakemore’s fnding. Frankel proposed that both discoveries be cited in

future publications concerning magnetotactic bacteria. However, his proposal suggests strongly that

Blakemore’s discovery led to the development of today’s scientifc community in magnetobiology and

bioelectromagnetism.

3.7 Discussion

How has the atmosphere-derived electromagnetic environment afected life on earth? Tere is no ques­

tion that the earth is not a closed system but an open system that extends into the atmosphere and into

space. For this reason, solar radiation and cosmic rays are also important sources of extraterrestrial

natural electromagnetic felds.

Natural electromagnetic felds are environmental factors for all biological systems. Teir origins

are basically the atmosphere, the terrestrial electromagnetic felds, the radiation from the sun, the

cosmic rays which are divided into non-ionizing radiation and ionizing radiation. All biological sys­

tems on earth live within and in harmony with these naturally originated electromagnetic felds and

radiation. In particular, the atmosphere is host to a electromagnetic environment generating from a

global electric circuit, atmospheric electric felds to local lightning strikes. Many environmental pro­

cesses may interact with atmospheric electricity including lightning, thunderstorm, climate changes,

etc. For a period of millions to a billion years, life on earth had the time in the evolution of the spe­

cies to adapt to the natural originated electromagnetic environment. On the other hand, ever since it

became possible to create man-made electricity, life has been also exposed to this man-made electro­

magnetic environment. Te earth is covered with electromagnetic radiations not only from natural

origin but also from man-made origin. Tese electromagnetic radiations are closely related to our

daily activity and life.

In this chapter, the intimate connectivity of atmospheric electricity with biological systems was pre­

sented briefy. It shows how atmospheric electricity can govern human well-being as well as a whole ani­

mal kingdom. In particular, the efects of the earth’s electric feld on living organisms and how they are

utilized by living organisms are discussed, as well as the relationship between the low-frequency elec­

tromagnetic felds generated by lightning discharges that occur constantly on a global scale and physi­

ological changes in humans and animals and the relationship between natural electromagnetic felds

and living things. It is also said that negative air ions produced by atmospheric electrical phenomena