Why your brain is like an ant colony: they both get wiser and more stable by using collective memory for learning
Deborah M Gordon is a professor of biology at Stanford University in California. She has written about her research for publications such as Scientific American and Wired. Her latest book is Ant Encounters: Interaction Networks and Colony Behavior (2010).
A red wood ant colony remembers its trail system leading to the same trees, year after year, although no single ant does. In the forests of Europe, they forage in high trees to feed on the excretions of aphids that in turn feed on the tree. Their nests are enormous mounds of pine needles situated in the same place for decades, occupied by many generations of colonies. Each ant tends to take the same trail day after day to the same tree.
During the long winter, the ants huddle together under the snow. The Finnish myrmecologist Rainer Rosengren showed that when the ants emerge in the spring, an older ant goes out with a young one along the older ant’s habitual trail. The older ant dies and the younger ant adopts that trail as its own, thus leading the colony to remember, or reproduce, the previous year’s trails...