The purpose of the investigation was to learn about the siamangs’ interactions with one another, not with humans, so Greysolynne made some adjustments. She learned to stand off to one side of the enclosure and speak her notes into a tape recorder instead of writing them. When she recorded the siamangs’ voices, she made sure to place the tape recorder (and herself) out of the gibbons’ reach. When she wanted to photograph the animals, she asked the photographer to set up his cameras half an hour early so that the siamangs had a chance to complete their through-the-glass inspection of the equipment and return to their normal behavior. Sometimes, when Greysolynne Fox stood recording her observations about the siamangs, zoo visitors would stop to ask what she was doing. “How can you tell the animals apart?” was a common question. “They all look alike to me.” Greysolynne would explain how she had very quickly learned to tell which siamang was which by head shape, amount of hair on head and body and patterns of hair distribution, and skin coloring on the face. It seemed to her that siamang looks were as individual as human looks. Of course, after a while, the siamangs could also be distinguished by their personalities. Each animal had its favorite spots in the enclosure, favorite foods, favorite pastimes. Suzy, for example, was quieter and played less than either Unk or the children. However, she loved to twirl around on a rope that hung from the top of the cage. When the rope was removed because it posed a danger to the young animals, Suzy began to hang by one hand from the overhead bars and twirl around on her own arm. Because Les was a newborn baby when the study began, it was possible for Greysolynne Fox to keep detailed records on infant siamang development and on changing relationships within the ape family. Until Les was nearly three months old, Greysolynne never saw him leave Suzy’s body. When he was not nursing or sleeping, he sometimes sucked his thumb or his big toe. During this time, Unk appeared to be totally uninterested in the baby. Perhaps experience with earlier offspring had taught him not to expect much response from such a young infant. Les’ older brother and sister, however, displayed none of Unk’s indifference. Smitty, who had never seen an infant before, was fascinated. He inspected Les with his eyes, nose, and hands while the baby clung to Suzy. Mark too reached out for the baby, but she was not permitted to touch him. Often, Suzy bit her daughter to chase her away from Les. In December, when he was three months old and had several teeth, Les sampled his first solid food. He also began to leave his mother for short periods of time, although Suzy watched him constantly. He became more of a playmate for his brother. Smitty appeared to enjoy tugging the baby to his feet by an arm or a leg. And at last, Mark was permitted to hold the baby. Sometimes, Suzy allowed her daughter to take care of Les for an hour or more, while she took a twirling break, or groomed Unk, or ate a leisurely meal.