Risky choice in pigeons: preference for amount variability using a token-reinforcement system.

Choi et al. (2012) let pigeons pick between two token piles. One pile always held the same number of tokens. The other pile varied: sometimes more, sometimes fewer.

The birds could trade tokens for food right away. The team then removed the tokens and ran the same choice again to see if the birds still liked the risky option.

With tokens in view, every pigeon chose the variable pile almost every time. They liked the gamble even when the average payoff was the same.

When the tokens disappeared, the preference vanished. Without the visible tokens, the birds picked the steady option. The tokens themselves, not just the food, controlled risk taking.

Davison et al. (1995) saw the opposite pattern in starlings. Those birds avoided variable food amounts when the average stayed equal. The clash is simple: starlings vs. pigeons, not a flaw in either study.

Doughty et al. (2010) showed pigeons and humans both like variable delays when tokens trade in right away. The new paper keeps the same quick-exchange setup but swaps delay for amount, proving the token effect works across both features.

Mueller et al. (2000) pushed the idea further in rats. They showed hungry rats lean toward variable pellets while well-fed rats play it safe. Together, these studies say: species, energy budget, and token visibility all shape risky choice.

If you run a token board or point system, remember the tokens are not neutral counters. Their mere sight can make kids chase the "maybe bigger" pile even when a sure, smaller pile is smarter. Watch for this when you offer variable bonuses or lottery-style rewards. If you want steady performance, deliver tokens without fanfare or skip variable amounts altogether.