How will technology change us as a species? In Silicon Valley, all prophesies seem to have converged into one: that it will usher in some sort of planetary Buddhist revolution. To read its mission statements and watch its Ted Talks is to hear phrases such as “connectedness”, “common understanding” and “overcoming barriers”. You could probably pitch a social media platform and a spiritual handbook simultaneously these days: “This will lead humanity to smiling, peaceful enlightenment.” The soothsayers in Hollywood, meanwhile, see it differently. Introduce new tech within a blockbuster film and things tend to go one of two ways. Awe and then terror, as the product wreaks havoc on the planet; or alternatively, the rise of an emotionless new society, where, surrounded by intelligent machines, people start behaving a bit like robots themselves. The stereotypical sci-fi citizen is cold, sombre, aloof and efficient. In the minds of scriptwriters, at least, tech will at some point leach the very humanity out of us. In the face of these three predictions, I give you the Portal: interactive sculptures set up in New York and Dublin with a live feed between them, so that passersby in the respective cities can see one another in real time. It was named like a sci-fi fantasy and made to look like one: a hole in the space-time continuum big enough to step through. According to the group behind it – Portals.org – its aim is to act as a “bridge to a united planet”, and to “invite all of us to meet above borders and differences”. How did humanity react to this lofty concept? Within hours of going live on 8 May, a “very drunk” woman in her 40s was led away and arrested on the Dublin side after repeatedly “grinding her bum” on the portal for 20 minutes. Another arse-flashing “incident” from the Irish soon followed, and then a Dubliner took things a step further by brandishing his phone showing footage of a plane crashing into the twin towers. Another man (also a Dubliner) flashed up images of a swastika. Another made a show of snorting coke. “Portal to hell: live video art installation already bringing out the worst in people,” lamented the New York Post. “Why did they put it here? At night-time it’s like The Purge,” a Dublin native told a newspaper. New York took matters into its own hands when a woman flashed her breasts at Dublin “in revenge” for the 9/11 image. “It was only fair I showed them my twin towers to save our city from harassment,” she explained. It was this that finally caused the Portal to be taken (temporarily) offline. The woman later revealed to be an OnlyFans star, and to have made about £8k in new subscribers from the stunt. The adolescent spirit of the internet is never more obvious than when it bursts into the real world Flashing, swastikas, OnlyFans. Is the Portal not a parable for the internet itself? Forget enlightenment, forget terror, forget the robotisation of humanity. Here might be the real answer to how hi-tech “connectedness” changes us. Offered a “bridge to a united planet”, we react by flashing, making rude signs and ganging up against each other. Far from pushing humanity into a higher level of sophistication, it causes us to regress into adolescence. The evidence has been pretty much there from the start. In The Psychology of the Internet, published in 1999, Patricia Wallace noted that online life – back then limited to email and chatrooms – was doing something strange to us. “One of the first surprises for researchers investigating online behaviour was how disinhibited people sometimes became, and how their tempers seemed to flare more easily as they interacted with others,” she wrote. We evolved, after all, for in-person communication, with its body language, nuance, half-meanings and potential for physical consequences. We know that even small amounts of physical separation can radically change behaviour: road rage, an incident of which went viral last week, boils up in the isolated container of a car. Experimenters note, too, that empathy drops off a cliff when people are separated by a glass window. How to summarise, then, the personality changes that the internet brings out in us? Tribalism, bullying, the wildfire spread of “crazes”, “instant gratification culture”, the triumph of the temper tantrum: future anthropologists might observe that the behaviour of adults online very much resembles that of children offline. I am often amazed at the rational common sense of those who don’t bother with social media, when asked about some topic tearing the internet apart. Online, there is a level of adult sophistication that simply seems beyond us. Some call the internet a town square, some a wild west. In fact, it’s a playground. The adolescent spirit of the internet is never more obvious than when it bursts into the real world. The 6 January 2021 attack on the Capitol was born online, which is why it appeared so strange: grown adults in fancy dress inflicting reckless damage and crying when arrested. With the Portal now closed, adult behaviour resumes around it – commuters trudge to work. On the internet, nostalgia fits here too: fantasy role play, video game characters, comic book culture, superheroes, all of these flourish. No surprise there: online life is infused with the morality of a children’s storybook: good and evil, and nothing in between. It is surely no coincidence that some of the personalities that triumph on social media – Andrew Tate, Jordan Peterson – find their strongest offline fanbase in pubescent boys. How will technology change us as a species? Humans once took adult wolves and arrested their development, turning them into childish dogs. It’s called neoteny: it’s how we domesticated them. Are we, in our turn, being domesticated by the internet? In the demand for content – silly, aggressive, playful, childish – are we gradually being turned into adult children? Martha Gill is an Observer columnist