Penguins, like many animals, are freaked out by people. Even if those people are well-intending researchers, the birds' heartbeats race when humans approach. So a team of scientists from the University of Strasbourg decided to design a monitoring method that wouldn't completely terrorize their research subjects, Wired reports.

A robot, the researchers figured, might be less threatening than a living, breathing, potentially predatory human. They equipped 24 king penguins in Antarctica with external heart rate monitors. The next day, they sent a remote-controlled rover into the penguin colony. They observed the birds from more than 650 feet away, Wired describes, and noted that their heart rates were significantly less fluttery and stabilized more quickly than when humans approached the animals. The penguins also allowed the rover to get closer to them before moving away from their nest than they would a human.

The researchers realized they were on to something—but a key ingredient was missing. What if they dressed the robot up to look like a baby penguin? Pursuing this hunch, they outfitted the rover with a big ball of fluff and a little penguin head and arms. The results were even better. The penguin chicks allowed the rover to join them in a creche (basically a big gathering of adorable baby animals that allows adults to keep an eye on them). They even tried to communicate with the rover.

"They were very disappointed when there was no answer," the researchers told the Associated Press. "Next time we will have a rover playing songs."

In addition to helping researchers monitor animals while causing as little disturbance as possible, rovers, the researchers think, could also be used to avoid putting humans in potentially dangerous situations. Another trial with elephant seals showed that those massive animals paid little if any attention to the undecorated rover, Wired reports. As the researchers point out in their paper, "This is notable as elephant seals generally react strongly when humans approach their tails.”