If people need one more reason to exacerbate their trust issues with big tech firms, Facebook's latest experimental algorithm should do the trick.
The social media giant has devised a way to recognise people using just the back of their heads.
The team at Facebook's artificial intelligence lab took 40,000 public photos from Flickr including pictures of people with their heads turned away from the camera and ran each image through a neural network.
Researchers found that the algorithm was able to identify people with 83 percent accuracy.
Like humans, the network was able to make its judgements using cues such as body size, hairdo and clothing.
Yann LeCun, head of artificial intelligence at Facebook told NewScientist:
"There are a lot of cues we use. People have characteristic aspects, even if you look at them from the back.
"For example, you can recognise Mark Zuckerberg very easily, because he always wears a gray T-shirt."
Facebook claimed that the experimental algorithm could help better its latest photo-sharing app 'Facebook Moments' that it released last week.
While Zuckerburg might be ok with his T-shirts being a giveaway, the algorithm does pose worrying questions around privacy for the rest of us who inadvertently end up in a picture that we didn't mean to be a part of, as often the case with images on Facebook.
The only antidote to this potential problem would be to avoid cameras at all costs.