Abstract

It is time to change the way we think about teenagers. Far from their usual media image, they are not society’s scourge – instead they are the pinnacle of human achievement. David Bainbridge, the University Clinical Veterinary Anatomist, is the first author to take a ‘zoological’ view of where teenagers came from and what they are for. Recent discoveries have now shown that teenagers are a unique human innovation, and that, remarkably, they are also the key to the unique success of the entire human race. We now know how and why the second decade of human life has become imbued with a heady mix of physical, mental, addictive, emotional and sexual change. Teenage biology and behaviour, often viewed as an unpredictable, idiosyncratic, disturbing mess, now snap into focus as a beautifully choreographed sequence of interwoven steps along the journey to becoming the most complex creature on earth.

Because of its pivotal role in the human experience, adolescence brings with it the most intense physical, emotional and amorous experiences of our lives. Because of this, evolutionary inheritance can make some people’s adolescence a joy they will treasure forever, while for others it marks the start of a decline into failure, insecurity, mental illness and suicide. We now know that the teenage years are not just an uncomfortable transition between innocent childhood and mature adulthood. Instead, adolescence – the central moment when all strands of our life collide – evolved for a very good reason. It is the single experience that makes us truly human.