By Kate Darling 

A robotics expert argues that our relationships with robots cast light on our attitudes to animals.

Thirteen years ago, I bought a small robot dinosaur. Pleo, the latest and greatest in robot pets, was modelled on a baby camarasaurus, with green, rubbery skin, a large head and big eyes. The animatronic toy moved in a lifelike way, wandering around the room, crouching playfully and purring when patted.

I showed Pleo off to a friend, telling them to hold it up by the tail. My friend complied, gingerly plucking the dinosaur up off the floor. As the robot's tilt sensor kicked in, we listened to Pleo's motors whir and watched it twist and squirm in its rubber skin, eyes bulging. After a second or two, a sad whimper escaped from its open mouth. As the robot began to cry out with more urgency, the feigned distress started to make me uncomfortable. 'Okay, you can put him down now,' I said, my words punctuated with a nervous laugh. Then I petted the robot to make it feel better.