Cell biologists led by Judith Campisi at the Lawrence Berkeley National Laboratory in California doubt that every cell has this dividing limit, and believe that it could be only those cells that have stopped dividing that cause ageing.

ECONOMIST: The latest from the wacky world of anti-senescence therapy

The genes for vaults are almost the same among all these different organisms a good indication to evolutionary biologists that whatever vaults do, it is crucial for the cell.

ECONOMIST: Cell biology: The secret of the vaults | The

The last time I checked with biologists, philosophers and even politicians on both sides of the debates about abortion, stem cell research and cloning, they were pretty certain human individuals were defined by two sets of chromosomes (half from the male, half from the female) which were arranged in the one-celled zygote after fertilization.

FORBES: Biologist Asserts Your Life Began...Before Fertilization.