Operant conditioning in the newly hatched chicken.

Researchers worked with newly hatched chicks. They wanted to see if the birds could learn to peck a key for food.

The chicks were only three days old. A small light came on before food appeared. This taught the birds when to peck.

The chicks learned fast. By day three they pecked only when the light was on. Later they followed simple feeding schedules.

This showed that very young animals can learn through operant conditioning. The key peck became a true operant response.

Herrnstein et al. (1979) built on this work. They taught pigeons to peck two times in a row. This proved whole sequences, not just single pecks, can be reinforced.

Stolz (1977) looked closer at the peck itself. Short pecks acted like reflexes. Long pecks changed with consequences. The chick study opened the door for this split.

Horner (1971) showed the same schedule control in bats. Henton et al. (1970) got similar results with blackbirds hopping for food. The chick paper was the first to prove operant learning works in day-old animals.

You now know that early learning is possible in any species you test. If you need to shape a new response with a young client, start early and use clear signals like the light used here. Remove extra toys or distractions so the target response stands out. Mirror the setup used with the chicks: one clear cue, one simple response, immediate food reward.