Crows flexibly apply statistical inferences based on previous experience.

Area of Science:

• Cognitive Science
• Animal Behavior
• Neuroscience

Background:

• Statistical inference is crucial for decision-making under uncertainty.
• Previously, statistical inference was believed to require human-level reasoning, but it has been observed in preliterate individuals, non-human primates, and birds.
• True statistical inference involves using relative, not absolute, frequencies.

Purpose of the Study:

• To investigate whether crows can perform statistical inference.
• To determine if crows can use memorized reward probabilities to make reward-maximizing decisions.

Main Methods:

• Two crows were trained to associate arbitrary stimuli with reward probabilities (10%-90%).
• Crows were then presented with choices between stimulus combinations.
• Their choices were analyzed to see if they maximized rewards based on stored probabilities, controlling for absolute frequency.

Main Results:

• Crows successfully retrieved and utilized memorized reward probabilities to make reward-maximizing choices.
• Behavioral effects (distance and size) indicated crows represented probabilities as abstract magnitudes.
• Crows' choices persisted even when absolute reward frequency was controlled, signifying true statistical inference.

Conclusions:

• Crows exhibit true statistical inference by employing relative reward frequencies for decision-making.
• This study extends the understanding of complex cognitive abilities, including statistical inference, to birds.
• The findings suggest that sophisticated decision-making mechanisms are not exclusive to primates.