Waiting for spring weather that may never come, they revert to strange primitive behavior, inventing dark rituals moment by moment.

She regards this as primitive behavior.

It was strange, Karellen thought, that so many human beings still seized every opportunity for primitive behaviour.

"What I don't understand is the primitive behavior exhibited by the creature."

"I'm afraid your primitive male behavior might slow us down."

This primitive behavior permanently shapes the lives of everyone involved.

"It's only high spirits," said Pelorat, who would have endured anything within reason that he felt came under the heading of primitive behavior and beliefs.

I just split the logs with old ax and put them on the fire, which is primitive and probably criminal behavior.

Even bacteria, which show primitive behavior as isolated cells, can display more sophisticated behavior as a population.