Series of Archaic Stage communities living on the coast of southern California in North America during the period 6000–1000 bc. Through this period the sea level in the area was rising and accordingly subsistence economies were changing. In the Ex Phase exploitation of shellfish and gathered plant food predominated, but in later phases deer and sea mammals became an increasingly common part of the diet. These changes coincided with a transition from crude percussion‐flaked lanceolate projectile heads to side‐notched and stemmed heads. Bone gouges and multi‐part barbed fish‐hooks also come into use. Houses of these phases include some sunken‐floor buildings.