Greatest number: The animal kingdom's working class they are, constituting 90 percent of all the species found on our planet, while including invertebrates they form 99 percent of life forms on earth. Insects are the life-forms most adapted, socially most advance, even their sexes are determined based on their working nature in their society.
Ecological importance: The sheer magnitude of insect numbers mean that they could not be eliminated without leaving a hole so large ... that the rest of the world's organisms would be unable to continue their lives.
The caste system: The caste system of insects enables eusociality the division of labor between non-breeding and breeding individuals. A series of polyphenisms determines whether larva develop into queen, workers and in some cases soldiers. In some ants, an embryo must develop under certain temperature & photoperiod conditions in order to become a reproductively-active queen. In bees, royal jelly provided by worker bee causes a developing larva to become a queen. Royal jelly is only produced when the queen is aging or has died.
Polyphenism: A polyphenic trait is a trait for which multiple, discrete phenotypes can arise from a single genotype as a result of differing environmental conditions.
Key of the caste: When a queen lays eggs, each egg can develop into a different caste depending on the environment it is in -- the temperature it develops at and the nutrition it receives. But the key to "switching" into a specific caste is controlled to a large extent by one chemical inside the eggs, which is called juvenile hormones.
Scientist believes this as unleashing of some kind of ancestral potential. That reveals the hidden evolutionary potential.
Giant super soldiers in lab: (ref: BBC, Nature News, 5 Jan 2012) Dr. Ehab Abouheif from McGill University in Montreal led the team which found that treating ant larvae with a hormone at a very specific time during their development turned those ants into the giant super soldiers.
More possible implication of this finding: Dr. Abouheif says that the unlocking desirable ancestral features could be key to breeding crop plants with higher nutritional value or even tracking the mechanism that causes cancer. "Who's to say that all of that crazy growth that occurs in cancer isn't the unleashing of some kind of ancestral potential," he said. "If we could find what that was, may be we could reverse it", reveals that hidden trait could be unlocked in many species.