Final answer:
Cognatic descent groups with a patrilineal bias refer to a kinship system where descent is traced through both parents, but there is a stronger emphasis on the male line, especially in matters such as surname inheritance. This reflects a blend of bilateral and patrilineal practices within a society, despite being fundamentally cognatic.
Step-by-step explanation:
When referring to cognatic descent groups with a patrilineal bias, it implies a kinship system where both male and female descent is acknowledged, but there is a preferential tilt towards tracing lineage through the male line. This system is ambilineal because it allows for descent to be traced through either the mother's or the father's line, but in practice, it is more common for families to follow the father's lineage. This can be seen in instances of family name inheritance, where children typically assume their father's last name, a trait indicating a patrilineal influence within a cognatic or bilateral system.
In societies like the United States, a cognatic or bilateral system is most prevalent, where kinship is traced through both parents. However, certain patrilineal aspects persist, as seen when children inherit their father's surname. This contrasts with matrilineal systems like those among the Crow and Cherokee tribes, where lineage is traced exclusively through the female line, and with ambilineal descent, where the choice between maternal or paternal lineage is made based on various factors like prestige or family custom.