Sydney Brenner (1927 - present) was awarded one-third of the 2002 Nobel Prize in Physiology or Medicine for his work concerning genetic regulation of organ development and programmed cell death. In search of a simple organism in which to study how development occurs, Brenner came across Caenorhabditis elegans, a transparent worm that, although only one-millimeter long, seemed full of potential. Brenner established the worm as a model organism for the investigation of animal development, including neural development. His work led to the first genetic map of a multicellular organism and paved the way to major revelations about programmed cell death and the regulation of organ development. Brenner also made important contributions to the emerging field of molecular biology in the 1960s, establishing the existence of messenger RNA and proposing the existence of codons (trinucleotide sequences that code for amino acids).