This research investigate the psychological and social effects of integrating artificial intelligence into collaborative work teams. Through three empirical studies, the authors explore how an AI teammate's social presence influences a person's motivation to contribute to collective tasks. The results indicate that while people initially perceive AI as having less presence than humans, this gap can be narrowed by increasing the transparency and familiarity of the system. Crucially, the studies reveal that social presence does not always drive productivity directly; instead, it works by fostering a willingness to depend on others and a sense of team-oriented commitment. Ultimately, the findings suggest that successful human–AI collaboration relies less on making robots look human and more on building interpersonal trust and clear operational understanding.