"WE are the strangest creatures on Earth," according to English author and scientist David Bainbridge.
Although there are plenty of other strange candidates in the animal kingdom, the Cambridge University veterinary anatomist does a pretty good job proving his assertion in his informative look at humanity's misunderstood middle age.
He does it by examining the common misconceptions about middle age and the odd behaviors that humans exhibit during their fifth and sixth decades.
He takes an evolutionary, anatomical approach to his subject, by which he means he compares and contrasts humans to other species in order to show how present-day people have evolved in genetically similar and different ways from other creatures.
He especially focuses on how we evolved from our fellow primates and our pre-agricultural ancestors.
We are (mostly) products of our genes. Natural selection continues to guide us through a middle age "life plan" according to a "developmental life-clock."
This approach has worked marvellously well in his previous popular science books: Making Babies: The Science of Pregnancy, The X in Sex: How the X Chromosome Controls Our Lives, Beyond the Zonales of Zinn: A Fantastic Journey Through Your Brain (a great title and his most fascinating study), and Teenagers: A Natural History.
Middle Age can be seen as a companion piece to 2009's Teenagers.
Bainbridge began Middle Age when he turned 40, a time when the offspring of many middle-agers enter their teenage years.
While this one isn't as lively and informative as the one on teenagers, it's not because middle age is an inherently dull and grim time, the beginning of an inevitable and depressing decline.
Nor is it merely a vague, ill-defined and boring transition between our dynamic teens and the gloom of old age.
For Bainbridge, middle age is "a definite, discrete part of human life, unlike any other."
He proceeds by asking and answering questions -- the main one being: what is middle age for?
Since humans have such a large brain ("roughly five times larger than one would expect in a mammal of our size") and take an inordinately long time to mature, middle age has evolved to become a time when our role as humans "changes from procreation and nurturing to provision and cultural perpetuation."
Middle age is a time for educating our offspring in the complexities and nuances of civilization.
How middle age will evolve now that the media, especially the Internet, seem to have taken over this education role is not something for Bainbridge to speculate about.
Instead he is intent on debunking myths (the so-called mid-life crisis and male menopause are inventions of the 1970s; empty nesting is an invention of the 1950s) and asking relevant questions.
The book is divided into 18 chapters, each one headlined by a question. Such as:
-- Is your mind 'complete' by the age of 40?
No, it's just reaching the "cognitive peak of the most intelligent being in the known universe." It's a great time of mental stability and a "perfect balance between cognition and emotion."
-- Does middle age mean the end of sexuality and vital, loving relationships?
No, it's "when romantic pairings are most stable, despite everything that conspires against them."
Along the way there are many fascinating digressions on such topics as the four phases of weight gain, how an MRI works, how Viagra works, what causes Down syndrome.
Middle Age is not a self-help book. But it's reassuring in an odd way.
"[B]y the time we reach middle age, we have finally grown up," Bainbridge concludes.
Middle age is not a crisis but a liberation.
A retired University of Manitoba film professor, Gene Walz is reluctant to admit he's past middle age. Sometimes he even thinks he's still in early adulthood.