Daily Devotional – May 24
Certain bacteria love to live in the mud, but they do not like oxygen. So, they need to know which way is down, that is, away from oxygen found in higher concentrations nearer to the surface of the mud. Large creatures use gravity to know which way is down, but bacteria are microscopic and do not have any apparatus to sense direction of gravity’s pull.
A graduate student studying these mud-loving bacteria noticed that they would congregate on the north side of the microscope’s slide. So, he placed a bar magnet on the opposite side of the slide, overriding earth’s magnetic field. Sure enough, the bacteria swam to the other side, thinking it was north. In the northern hemisphere, the further north one goes, the more a compass needle dips toward the center of the earth; at the North Pole, the needle dips straight down. If a bacteria had an internal magnetic compass, it would not only guide itself north, but it would have the ability to sense which direction was down and away from oxygen within a mud layer.
Upon further investigation, each bacterium was found to have molecular sized particles of magnetized iron (magnetite or lodestone), arranged in a line along the axis of the cell. Each piece of magnetite was roughly cubic and only about 50 nanometers (or one millionth of a millimeter) on each side. Mankind has never been able to make magnetite particles this small! Since that first discovery of bacteria having a built-in compass, dozens of varieties have been found displaying this same magnetic response. Bacteria with compasses; Jesus loves to surprise us with His creativity!
The north and the south thou hast created them….
~ Psalm 89:12
Source: "Pearls in Paradise" by authors Bruce Malone and Jule Von Vett
References for this devotional.