Biology concerns all living and evolving organisms - bacteria, Archea and the Eukaryota: plants and animals. Sometimes biologists look also for biomolecules which can evolve and propagate - e.g. viruses, and artificial life(AL). Biology is one of the most expanding fields of science, and many interesting things are happening in biology nowadays.The main theory in this field of natural sciences is called neodarwinism or Synthetic Theory of Evolution (STE).