blue dragonfly Biology is the scientific study of living things. Biologists define “living things” as all the diverse organisms descended from a single-celled ancestor that evolved almost 4 billion years ago.Because of their common ancestry, living organisms share many characteristics that are not found in the nonliving world. Living organisms: • consist of one or more cells • contain genetic information • use genetic information to reproduce themselves • are genetically related and have evolved • can convert molecules obtained from their environment into new biological molecules • can extract energy from the environment and use it to do biological work • can regulate their internal environment This simple list, however, belies the incredible complexity and diversity of life. Some forms of life may not display all of these characteristics all of the time. For example, the seed of a desert plant may go for many years without extracti...