Flexi Says: The first forms of life were simple single-celled organisms. Although single-celled organisms such as bacteria do not have a nervous system, they may communicate with each other and even identify the number of similar species in their vicinity by releasing chemicals. They might even navigate their environment to meet their needs. For example, the algae Chlamydomonas move towards light for photosynthesis. Some bacteria such as E.coli may also have the ability to learn and memorize. For example, in the human body, E.coli moves around to find lactose. Then it begins biochemical reactions to digest the lactose so that it can have the maltose that is left over.
