“There is one thing I want to make clear at the outset,” Dr David Bainbridge stresses in his new book Middle Age: a Natural History. “There is one reason and one reason only why I bought a Lotus.” It was not, he says, to make him feel better about hitting middle age, or to impress younger women. Instead, by buying a sleek sports car he was fulfilling a boyhood dream. “The fact that I actually did it at the age of 41 is mere coincidence.”
In a talk on 27 October at this year’s Festival of Ideas (www.cam.ac.uk/festivalofideas), the UK’s only festival devoted to the arts, humanities and social sciences, Bainbridge will ask what are the benefits of middle age and why did we evolve it?
According to Bainbridge, a Clinical Veterinary Anatomist in the Department of Physiology, Development and Neuroscience: “Middle age is a special, novel part of the human life-plan that has evolved because it has benefits for each of us as individuals.” And many of those benefits centre on our brains.
Compared with fast cars, many other changes that coincide with middle age are less appealing. Fat settles around the midriff, hair greys as follicles lose melanin, and skin sags as collagen and elastin deteriorate. “The loose, fibrous capsule of the breast gradually deteriorates,” he explains, “and many middle-aged men notice their testicles creeping into the distance as the scrotal skin stretches.”
But it was Bainbridge’s eyesight that first alerted him to impending middle age, he says. “I first became aware that I could not focus on nearby objects when I was 40 – the realisation came suddenly one day when I was peering around the back of computer to plug in a connector.” And its suddenness was one of the reasons he embarked on a book about the fifth and sixth decades of life.
Together with our teenage years, which he tackled in his previous book, Bainbridge is fascinated by middle age. Both are often viewed negatively and as transitional phases – things to be passed through en route to adulthood or old age. But, he argues, middle age is not part of a gradual, uncontrolled decline. The fact we all go grey, develop wrinkles and stop being able to focus on near objects at such a similar time suggests that middle age is a discrete phenomenon. And seeing it in this way helps us to understand what it’s for and why it is uniquely human.
“The reason they both fascinate me is that they aren’t really phases of life that other animals have,” he explains. “They’re quite distinctive, but other animals don’t have them, which implies that humans evolved them for specific reasons. That’s really what hooked me as a zoologist.”
“Forget your crow’s feet and revel in the fact that the middle-aged brain is the most powerful, flexible thinking machine in the known universe”
During his career as a veterinary anatomist and clinician working not only with animals but also their owners, Dr Bainbridge has come to realise just how bizarre and freakish humans are as a species. “As a scientist you work on whichever animal you think is an interesting model. So lots of medics end up working on animals, and quite a lot of zoologists end up working on humans,” he says.
“The animal that interests me now is the human, because I hadn’t realised how extremely weird we are. I’d always thought that we’re a mammal just like any other, but when you add together the catalogue of weird, exceptional things – standing on two legs, tool use, language, brain size, menopause, extreme investment in offspring, extreme social complexity – many of them are unique, some of them are extremely unusual, but having them together in one species is just begging loads of questions. I suppose that’s what I spend my time doing really.”
So while some of us fret about the small things we forget, or our inability to do certain mental tasks as quickly as we were once able, Bainbridge is upbeat about the power and influence of the middle-aged brain. “The crude thing that happens in middle age is that you can’t think as quickly,” he says. In any test involving time pressure, young people will do better. But if you’re measuring complexity, it’s a different story. “And if you brain-scan people doing intelligence tests, middle-aged people start to use different parts of their brain to do the same tasks compared with younger people. They are fundamentally different creatures and approach things in different ways,” he says.
Surviving into middle age is not new – it has happened for most of human history (until the advent of farming) and is, therefore, the result of evolutionary forces. And the reason natural selection still acts on humans at this age is because their brains are useful to a species that invests so much in the grey matter of its young. “Cultural transmission gives people an evolutionary importance far beyond that conferred by their crude ability to breed,” he explains. “This information-conveying role is a major reason why people survive beyond their reproductive years.”
Far from being over the hill, Bainbridge says those in middle age “are, in fact, luxuriating in the sunshine of the hill’s broad summit” – something to celebrate rather than regret.
Now embarking on his sixth book (on female body shape), he traces his penchant for popular science writing to working as a vet and his endless curiosity. “Having been a vet in practice, I realised that I had to explain complex biological concepts to intelligent people with no background in biology. I’d have a solicitor whose cat had become diabetic and I’d have to explain it to them, and I always found that very rewarding. When you’re a scientist you can discover all this stuff in the literature and you think – why does nobody know about this? It’s absolutely fascinating,” he says.
So, for a man who enjoys a good turn of phrase, it seems appropriate that Bainbridge’s main regret about middle age is not what is happening to his eyes or his paunch, it’s a line he wishes he had thought of to describe his Lotus. “I call my car my male menopause mobile, but as soon as the book came out someone emailed me with a better one. He’s an anaesthetist at Addenbrooke’s and he says he has a friend – I’m sure it is a friend – who bought a flashy new Audi that he calls his concubine harvester. And I thought why didn’t I have that before the book came out? It’s far better.”