"You can tell why some people came here, like the big muscly men who clearly like parading around in thongs," said Damien Largey, 23.
Melissa Wecker, 21, was disappointed that the humans were wearing swimsuits beneath their fig leaves. "They're not doing anything. It looked lots better on the news," she complained.
Mark Ainsworth, 21, also heard about the Human Zoo on the news.
"I've lived in this country for nine years and have never come to a zoo," said Ainsworth, who came with Wecker. "This exhibit made us come to the zoo. Humans are animals too."
The human captives were kept well-fed and watered by zoo staff, who took care to ensure they did not grow bored. A supply of board games was on hand, and some said they were looking forward to tuning into the England-Australia cricket match on the radio.
Unlike the zoo's non-human inhabitants, they are allowed to go home each night at closing time. The event runs until Monday.
When visitor Peter Bohn, 42, saw the "animals" juggling, he stopped and had a good laugh.
"It's hilarious," he said. "It turns everything upside down. It makes you think about the humans in relation to the animals."
After three hours strutting his stuff on a cool late-summer day, Mahoney said he was still having fun, except when the wind picked up. But, he added, "I wouldn't do it if I didn't enjoy it."