Spark Notes is a recurring series about the lightbulb moments in sexual development. My parents were both readers, and they didn't let us watch that much TV. By the time I was 11, books had been my primary source of entertainment for as far back as my memory could go. Getting my adult library card in sixth grade was, in that context, a milestone of tremendous importance, a first moment of awe at being inducted into the grown-up world. Wandering into the adult stacks for the first time, I remember seeing the name Asimov in the "A" section in huge letters across dozens of titles, and taking two or three of them down to check them out.

Artificial intelligence can figure out a person's sexual orientation by analysing a picture of their face, a controversial new study claims. According to its authors, who say they were "really disturbed" by their findings, the accuracy of an AI system can reach 91 per cent for homosexual men and 83 per cent for homosexual women. The study also concludes that homosexual men and women tend to have "gender-atypical facial morphology, expression, and grooming styles". The paper, titled Deep neural networks are more accurate than humans at detecting sexual orientation from facial images, was co-authored by Stanford University's Yilun Wang and Michal Kosinski, and first spotted by the Economist. In it, they claim to "show that faces contain much more information about sexual orientation than can be perceived and interpreted by the human brain".