of relationships. Early experiences with caregivers gradually give rise to a system of thoughts, memories, beliefs, expectations, emotions, and behaviours about the self and others. This system, called the "internal working model of social relationships", continues to develop with time and experience. Internal models regulate, interpret, and predict attachment-related behaviour in the self and the attachment figure. As they develop in line with environmental and developmental changes, they incorporate the capacity to reflect and communicate about past and future attachment relationships. They enable the child to handle new types of social interactions; knowing, for example, an infant should be treated differently from an older child, or that interactions with teachers and parents share characteristics. Even interaction with coaches share similar characteristics, as athletes who secure attachment relationships with not only their parents but their coaches will play a role in the growth of athletes in their prospective sport. This internal working model continues to develop through adulthood, helping cope with friendships, marriage, and parenthood, all of which involve different behaviours and feelings. The development of attachment is a transactional process. Specific attachment behaviours begin with predictable, apparently innate, behaviours in infancy. They change with age in ways determined partly by experiences and partly by situational factors. As attachment behaviours change with age, they do so in ways shaped by relationships. A child's behaviour when reunited with a caregiver is determined not only by how the caregiver has treated the child before, but on the history of effects the child has had on the caregiver. Cultural differences In Western culture child-rearing, there is a focus on single attachment to primarily the mother. This dyadic model is not the only strategy of attachment producing a secure and emotionally adept child. Having a single, dependably responsive and sensitive caregiver (namely the mother) does not guarantee the ultimate success of the child. Results from Israeli, Dutch and east African studies show children with multiple caregivers grow up not only feeling secure, but developed "more enhanced capacities to view the world from multiple perspectives." This evidence can be more readily found in hunter-gatherer communities, like those that exist in rural Tanzania. In hunter-gatherer communities, in the past and present, mothers are the primary caregivers but share the maternal responsibility of ensuring the child's survival with a variety of different allomothers. So while the mother is important, she is not the only opportunity for relational attachment