Queen bees and worker bees are genetically identical, yet queen bees lay up to two thousand eggs a day, while worker bees are functionally sterile. Queens live up to three years; workers may live only three weeks.105 The difference between the two is diet. When the hive’s queen is dying, a larva is picked by nurse bees to be fed a secreted substance called royal jelly. When the larva eats this jelly, the enzyme that had been silencing the expression of royal genes is turned off, and a new queen is born.