The Crow and the Pitcher

It relates ancient observation of corvid behaviour that recent scientific studies have confirmed is goal-directed and indicative of causal knowledge rather than simply being due to instrumental conditioning.

[7] Modern equivalents have included English tiles from the 18th[8] and 19th centuries[9] and an American mural by Justin C. Gruelle (1889–1978), created for a Connecticut school.

The greatest diversity is in the type of vessel involved and over the centuries these have varied from a humble clay pot to elaborate Greek pitchers.

Further research established that the birds understood that the pitcher must contain liquid rather than a solid for the trick to work, and that the objects dropped in must sink rather than float.

The research also indicated that physical cognition evolved earlier in the corvid family than previously thought as the not closely related crows and ravens were already known to score highly on intelligence tests, with certain species topping the avian IQ scale[21] and tool use is well-documented.