For the earliest tribes 是表示“对于最早的部落”,为介词短语,但不是做时间状语.
sufficiency为主语,the concept of 做前置定语.
was more important than 是谓语短语
quantity 做宾语,the concept of 做前置定语.
句子主干：sufficiency was more important than quantity.
希望我的回答能够帮到您,祝好!请问for the earlist tribes 在句中是什么成分呢？前置介词短语做定语，修饰sufficiency。sufficiency是earlist tribes的sufficiency。