Final answer:
In America, the common descent type is bilateral descent, where kinship is traced through both parents' lines, unlike unilateral descent which follows one parent only. The U.S. practices mostly bilateral descent but shows elements of patrilineal descent, like children taking their father's surname.
Step-by-step explanation:
The common type of descent in America is bilateral descent, which means that one’s kinship is traced through both the mother's and father's lines. This contrasts with unilateral descent, where lineage is traced through one parent only, either the mother (matrilineal) or the father (patrilineal). While the bilateral system is prevalent in the United States, with both paternal and maternal ancestors considered as part of one's family, patrilineal descent is common in some societies, like in rural China and India, where only males carry on the family surname and are seen as the permanent family members.
In the U.S., there is a tendency towards patrilineal practices, such as in the common tradition of children assuming their father's last name. However, the society largely practices bilateral descent for recognizing ancestry and family connections.