The name of the given cell division in eukaryotes cell is meiosis and mitosis. Thy both work together to make sure the system works well. If their is a problem with the cell division, these cells become paralyzed.
There are two kinds of cell division in Eukaryotes: Mitosis where both cells are identical and Meiosis where the child cell has less chromosomes than the parent.
I don't know if this helps or not but you would want to know the age of the rock (absolute dating) and from there you will be able to know the age of the fossil and what caused it to die.
