Our brighter ancestors would have survived better and attracted more mates.
In that case, how could our ancestors possibly have survived?
This is not how your ancestors survived," he told them, "by ignoring a problem.
It is amazing your ancestors survived long enough to develop space-flight.
The bush ancestors from whom he had descended had survived by being fear-selected.
"If the whole planet is like this, it's hard to see how your ancestors survived."
But while the body's responses to stress helped our ancestors survive, they may be doing us more harm than good.
Our ancestors survive somewhere in our faces, she thought.
Without claws, wings or other natural weapons, human ancestors survived by watching one another's backs.
This is the world our ancestors negotiated - and survived long enough to pass on their cognitive apparatus.