Sense
Magnetoception (or magnetoreception) is the ability to detect the direction one is facing based on the Earth's magnetic field. Directional awareness is most commonly observed in birds, which rely on their magnetic sense to navigate during migration. It has also been observed in insects such as bees. Cattle make use of magnetoception to align themselves in a north-south direction. Magnetotactic bacteria build miniature magnets inside themselves and use them to determine their orientation relative to the Earth's magnetic field.
Magnetospirillum
Probably the most peculiar characteristic of "Magnetospirillum" species is their capacity to orient themselves according to Earth's magnetic field, magnetotaxis. This is achieved through the presence in the bacterium's cytoplasm of special organelles called magnetosomes. "Magnetospirillum" species also resort to aerotaxis, to remain in favorable O concentration conditions. When the bacteria ingest iron, proteins inside their cells interact with it to produce tiny crystals of the mineral magnetite, the most magnetic mineral on Earth.