Final answer:
Living or eating together, which may lead to adoption or fostering, can serve as additional kinship strategies in human societies.
Step-by-step explanation:
Behaviors that may constitute an additional kinship strategy include living or eating together, which may lead to adoption or fostering. In many cultures, families may choose to live together or share meals, even if they do not have a genetic relationship. This practice creates a sense of kinship and familial bonds, similar to adoption or fostering.