Final answer:
The behavior that baby Ian is demonstrating is the Moro reflex. This reflex helps the baby reach out and grab onto their caregiver for support and protection.
Step-by-step explanation:
The behavior that baby Ian is demonstrating is the Moro reflex. The Moro reflex is also known as the startle reflex, and it is an instinctive response that occurs in infants when they experience a sudden loss of support or a feeling of falling. In this reflex, the baby arches their back, extends their legs, throws their arms outward, and then brings their arms in toward their body. This reflex helps the baby reach out and grab onto their caregiver for support and protection.
The Moro reflex is present in infants from birth until about three or four months of age, after which it gradually disappears as the baby develops more control over their movements. It is an important reflex in the first months of life as it helps the baby maintain physical contact with their caregiver and increases their chances of survival.