Final answer:
The Ancestral Puebloans collaborated for survival by building strategic, community-centered settlements with multi-story structures, engaging in trade, and developing a strong agricultural base centered around maize cultivation.
Step-by-step explanation:
The ancestral Pueblo, also known as the Ancestral Puebloans or Anasazi, collaborated to ensure the survival of their community by constructing carefully planned towns such as Pueblo Bonito. Their settlements featured large, open plazas for community gatherings, multi-storied apartment-like buildings for housing and storing harvests, and strategic placement of dwellings in cliff dwellings or atop mesas for protection. The Puebloans were skilled potters, and trade networks were central to their economy, with a road system linking towns and connecting them to a wider regional economy. Their agriculture, including the cultivation of maize, in combination with a cooperative community structure, was vital for their resilience in the challenging environment.