Sense Electricity/Magnetism From the Environment
Some living systems use electric or magnetic signals as a way to receive information from their environment. Magnetic and electric fields can help such living systems determine direction, altitude, or location, and electric fields also help living systems find other living systems. Detecting and interpreting electrical and magnetic signals requires specialized techniques. For example, mud-dwelling bacteria use crystals composed of magnetite to sense geomagnetism, which helps orient the bacteria to burrow deeper into the mud.
Sense Atmospheric Conditions
For some living systems, the ability to detect changes in atmospheric conditions can be very valuable. By predicting changes in regional weather or in very localized conditions, living systems can avoid or take advantage of those changes. Since such adjustments can be very subtle, living systems must be able to detect miniscule variations in moisture, barometric pressure, ions in the air, and other environmental cues. Many insects and birds, for example, can predict oncoming storms and take cover before their lives are put at risk.