There has been a debate--and it's still a raging debate--about whether animals, not just apes,
are capable of planning and preparing for the future in the absence of a current need.
How can people go about testing this?
For instance, you can give them enough food, food that they like, until they are sated.
They don't want it anymore.
And then, in order to get this food, they need to use a tool--a special tool.
So you let them use that tool, and once they are finished eating now they go away,
and the next day they come back.
But when they come back the next day, the tool is not there.
So in order to solve this problem, what they have to do
is they have to take this tool with them and then bring it back tomorrow.
If they can do that, then that is evidence that they are planning for tomorrow.
They are taking this tool.
They are transporting it.
They are saving it overnight so that they can use it tomorrow.