Reasons why human beings are unique
if there is something in it for them.
"Humans do that too, but in addition they care about what their partner gets.
In some experiments we have children as young as 14-18 months who seem
to expect their partner to collaborate in certain ways and who share in ways
chimps don't."
Human children are less selective about who they share with. Chimpanzees
though, largely only share with close relatives, reciprocating partners or
potential mates.
Felix Warneken of Harvard University in Cambridge, US, differentiates it like
this. Children are "proactive", that is, they help even when presented with
only very subtle cues. Chimpanzees though, need more encouragement.
They are "reactive": they will hand over objects but only after some nudging.
What happened in our evolution to make us reliant on each other?
Something must have happened in our evolution, Tomasello says, to make
humans increasingly reliant on each other
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