The most fundamental physical mechanisms which are involved in the biological systems are dealt and studied in the new branch of science called Quantum biology. Findings resulting from these investigations shed light on the possible role of quantum mediated processes in crafting the primitive life forms and in the emergence of conscious life. Since biological evolution began much after the existence of energy and matter and its unanimity, the answer to the origin of life actually lies much before the emergence of viruses, bacteria, archaea and eukaryotes. According to Gaia theory, after the formation of biological matter from chemical constituents there exists a mutual and dynamic interaction between the two resulting in the process of co-evolution. This means that biological systems interact with surrounding inorganic matter to form a complex, self-regulating and dynamic synergistic system of ecology which helps in perpetuating and maintaining the conditions for life (Schneider and Boston).
Microbial intelligence (popularly known as bacterial intelligence) is the intelligence shown by microorganisms. The concept encompasses complex adaptive behavior shown by single cells, and altruistic or cooperative behavior in populations of like or unlike cells mediated by chemical signaling that induces physiological or behavioral changes in cells and influences colony structures.
Complex cells, like protozoa or algae, show remarkable abilities to organize themselves in changing circumstances. Shell-building by amoebae reveals complex discrimination and manipulative skills that are ordinarily thought to occur only in multicellular organisms.
Even bacteria can display more sophisticated behavior as a population. These behaviors occur in single species populations, or mixed species populations. Examples are colonies or swarms of myxobacteria, quorum sensing, and biofilms.
It has been suggested that a bacterial colony loosely mimics a biological neural network. The bacteria can take inputs in form of chemical signals, process them and then produce output chemicals to signal other bacteria in the colony.
Bacteria communication and self-organization in the context of network theory has been investigated by Eshel Ben-Jacob research group at Tel Aviv University which developed a fractal model of bacterial colony and identified linguistic and social patterns in colony lifecycle.