Honey bees learn to associate flower colour, scent and shape with the quality of the nectar or pollen reward they find there — a form of associative learning first demonstrated in the lab using the proboscis extension reflex (PER), where a bee reflexively extends its tongue when it smells an odour it has learned predicts sugar water. Despite a brain of under a million neurons (roughly a million times fewer than a human's), bees form durable memories after only a handful of rewarded visits.
V += α × (reward − V). Landing on an unrewarded colour weakens it.Bees can also learn abstract relational rules (such as "same" vs. "different", or basic notions of "zero" and simple arithmetic), and they navigate over kilometres using a sun-compass corrected for the time of day, plus a mental map built from landmarks — remarkable feats for a brain not much bigger than a grass seed.
A single foraging bee repeatedly visits patches of coloured flowers; only one colour hides real nectar, and with each trip her associative memory for every colour updates, letting you watch simple learning and forgetting unfold live.
Each visit reinforces or weakens a colour association following a Rescorla–Wagner-style update rule, while unused associations quietly decay — a minimal model of how a brain of under a million neurons still learns fast and remembers selectively.
Pick the rewarded colour, tune the learning rate and forgetting rate, and watch the association bars rise for the profitable flower and fade for the rest. Flip on extinction test to see a learned preference collapse once the reward disappears.
Real honey bees can be trained in the lab using the proboscis extension reflex (PER) — after just a few pairings of an odour with sugar water, they reflexively extend their tongue to that odour alone, a textbook demonstration of associative learning in insects.