Observations on the behavioral development of two okapi calves and one giraffe calf were made at Brookfield Zoo. The following behaviors were monitored for 4 to 6 mo after birth: nursing duration and nursing attempts, mother-infant distance, bunting the mother’s udder, lying, moving, maternal grooming, mother and infant autogrooming, object licking, tail chewing, and contact by others in the herd. Behaviors in both species showed oscillating patterns with high levels of mother-infant contact behaviors at 3-4 wk, 9-11 wk, and