Creating bent tools to fish for food in holes and crevices seems to come naturally to a species of crow.

Credit: James St Clair

In 2002, a captive New Caledonian crow (Corvus moneduloides) called Betty astonished scientists by bending straight pieces of wire into hooked tools to access out-of-reach food. But recent field experiments by Christian Rutz and his colleagues at the University of St Andrews, UK, show that bending is used by wild New Caledonian crows, too (pictured). More than half of the 18 wild-caught crows in the study bent sticks during routine tool manufacture, using methods similar to those used by Betty to handle wire. Most birds stood on the sticks and pulled the tip up.

This discovery suggests that bending may have been part of Betty's natural tool-crafting repertoire, rather than a smart invention.

R. Soc. Open Sci. 3, 160439 (2016)