The rank of an ant in its colony's caste is now understood to be determined by genetics. Evolutionary biologists at Johannes Gutenberg University Mainz (JGU) have found in a recent study that an ant's DNA controls not only physical differences, but behavioral ones as well.

Genetics Determine Division of Labor in Ants Within an ant colony, it is genetics that determine an individual’s position rather than other factors such as age or size.
Evolutionary biologists have found this genetic determination of labor to be present in other insect societies as well. In an ant colony, the drastic difference of a member’s behavior is often paired with variations in physical appearance and physiological function. A soldier ant, for example, can weigh up to 100 times more than the brood care workers with whom they share the same gen...
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