1. Branches and leaves: These were the most readily available materials and were used to create simple lean-to shelters or more complex structures such as huts.
2. Animal skins: These were used to create tents or to cover the frames of other shelters.
3. Grass: This was used to create thatch roofs for shelters or to make mats for flooring.
4. Bark: This was used to create roofs or walls for shelters.
5. Mud and clay: These were used to create adobe structures or wattle and daub construction, where wooden frames were filled in with mud and clay.
6. Stone: This was used to create more permanent structures, such as caves, rock shelters, or dry-stone structures.
7. Wood: This was used to create frames for shelters, as well as to make furniture and other items.
The specific materials used for shelters would vary depending on the region and climate, the availability of materials, and the cultural traditions of the hunter-gatherer group.