'Sophisticated Toy' Takes Over

For a better understanding of what's going on between man and machine, "Nightline" traveled to the University of California at Berkeley, where scientists are conducting the latest research into robot-human relations.

Pleo is a popular robotic dinosaur.

(Handout)

Their new number one test subject: Pleo.

"The machine isn't important," one scientist said. "What's important is the human and what the human believes and the meaning the human gets from the machines."

Better Than a Real Pet?

ABC News conducted a less scientific experiment, taking Pleo to a nearby outdoor mall, where it didn't take long for kids and adults alike to warm up to him. And when it came time to give Pleo back, tears were narrowly averted.

Linda McKenzie certainly understands how quickly one can become attached to Pleo.

"If something happened to him, there would be a lot of tears," she said.

But before getting all choked up, it's important to know that Pleo's not cheap. It costs about $350.

Owners say that's a lot less than a real pet and there's no mess to clean up — just batteries to charge.