NEW Caledonian crows may be smart, but are they schemers? A series of tests designed by Joanna Wimpenny and Alex Kacelnik at the University of Oxford shows the corvids can upgrade tools in succession to obtain an otherwise unreachable snack. But Kacelnik cautions against jumping to the conclusion that the birds can plan two steps ahead.
Wimpenny and Kacelnik tempted seven crows with a bit of pig heart trapped down a clear tube. To snag the treat, the birds had to use a short stick to ferret an intermediate stick out of a tube. They then had to use this…
