Complex sentence: They feature many different designs (bears, birds, frogs, people, and various supernatural beings and aquatic creatures) that function as family or chiefly crests and to recount stories owned by those families or chiefs, and/or to commemorate special occasions.
Split into simpler sentences: They feature many different designs (bears, birds, frogs, people, and various supernatural beings and aquatic creatures) that function as crests of families or chiefs. They recount stories owned by those families or chiefs, and/or commemorate special occasions.