forerunner
     n 1: anything that precedes something similar in time;
          "phrenology was an antecedent of modern neuroscience"
          [syn: {antecedent}]
     2: a person who goes before or announces the coming of another
        [syn: {precursor}]
     3: an indication of the approach of something or someone [syn:
        {harbinger}, {herald}, {precursor}]
Source: WordNet® 2.0