An unlikely feature on this morning's Today programme on Radio 4 about Leaf Cutter ants and their performance in the work place seems very relevant to 2011 when the default retirement age is going to be abolished and employees can work longer. The research from Schofield et al "measures the efficiency of leaf cutter ants' mandibles". These are the ants whose duty it is to cut and carry something like 50 times their size in leaves (Tom and Jerry style).
As the ants wear with age the individuals with the most worn jaws are less than half as effective at cutting. Instead of making the ants redundant or them just dying, their role changes and they spend more time transporting leaf fragments sliced from their sharper sisters IE they still have a valuable contribution to make but that contribution has changed. Maybe there is something for us humans to learn from these tiny and industrious creatures for the new year.