The ultimate and transient effects of a catastrophe which eliminates a fraction of an age group in a population

A catastrophe which eliminates a fraction of an age group in a population is investigated, and the asymptotic reduction in the population is obtained. It is shown that the loss of a youthful group is ultimately more damaging than the loss of an older group. An investigation of the transients following a catastrophe shows that they are reduced to less than 1% of the steady state after a small number of generations.