You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Hunter-gatherer

Context:
At the 1966 "Man the Hunter" conference, anthropologists Richard Borshay Lee and Irven DeVore suggested that egalitarianism was one of several central characteristics of nomadic hunting and gathering societies because mobility requires minimization of material possessions throughout a population. Therefore, no surplus of resources can be accumulated by any single member. Other characteristics Lee and DeVore proposed were flux in territorial boundaries as well as in demographic composition.

Question:
What other characteristic is variable for these groups?

territorial boundaries