Coloured cell lineage drawings for the C. elegans worm 

Wellcome Library | Object | Human Genome Project

Cell lineage refers to the development of cells within an organism from their embryonic state to their final, realised function. Observing cell lineage helps to consider what determines the fate of a cell. Is the cell’s ultimate function pre-programmed or does it respond to its environment? Using a specially adapted microscope John Sulston spent 18 months observing and drawing nematode embryo cell division in real-time. He drew what happened to each cell after division using three different colours to show the position of the cells relative to each other – red on top, green in the middle, and black on the bottom. For this important work that had wider implications for other organisms, including humans, Sulston, and his co-researchers Sydney Brenner and Robert Horvitz, received the 2002 Nobel Prize for Physiology or Medicine.