First of two parts

I have a fascination for our natural world that has been with me since childhood, and I am inexpressibly fortunate in being able to travel — in part through work as a nature-tour guide — to see some of the greatest natural wonders of the world each year.

The thrill and excitement of witnessing nature's dramas unfold around me does not diminish — whether it's the visible migration of flocks of swans, geese and other waterfowl through Hokkaido each spring and autumn; the packed beaches of immense Steller's sea lion and northern fur seal rookeries in the Russian Far East; the sight of a rare northern woolly spider monkey (also known as a muriqui; Bracyteles hypoxanthus) nurturing its newborn youngster in the Brazilian Atlantic Forest; or a herd of reintroduced Przewalski's horses thriving on the central Mongolian steppes.

We live in a remarkable world that, despite hurtling through inhospitable and hostile space at unimaginable speed, still manages not only to support life but also to support an incredible and breathtaking diversity of forms of life — most of which we barely know, let alone understand.

I liken this reality to living in a completely crowded convention room wherein we know the names of just a handful, perhaps as few as 10 percent, of the other people there. We look beyond those we know to a sea of faces that we can identify with, but know nothing about, while only some of us realize that the crowd at the front hides an even greater sea of invisible faces beyond.

As a species, we were born — in an evolutionary sense — into a rich, full world uniquely capable of supporting self-replicating life in myriad forms, and we have so much yet to learn about it.

With the meeting of COP10 (the 10th Conference of the Parties) to the U.N. Convention on Biological Diversity (CBD) taking place (Oct. 18 to 29) in Nagoya as I write, it's hardly surprising that my mind has turned this month to the subject of our Earth's "proliferance" — what the British evolutionary biologist Richard Dawkins has aptly referred to in the title of his eminently readable 2009 book, "The Greatest Show on Earth" — and whether we are yet able to understand the very depths of our fundamental dependence on it for our life-support systems.

I happened to be born and to grow up in a small industrial town in the English Midlands county of Worcestershire, almost as far from the sea as you can get in the United Kingdom. Like many a child in England in the mid-1950s and '60s, I was also about as isolated from nature as you could be.

Thankfully, though, it was still considered safe in those days for children to play outside, and one of my early childhood memories is of peering into a bird's nest in a hedgerow and marveling at its delicate, living content. How could such fragile beauty survive with only a small winged creature to build such a cradle and care for it?

What I had no inkling of then was that, within my own lifetime, the question of the survival of such fragile beauty would extend far beyond individuals to so many of the species with which we share the Earth. Indeed, that issue would become inherent in all questions concerning our own survival as a species.

A confusion of memories jumbles my early years together, but that confusion references delight in nature of all sorts, particularly the birds visiting our small suburban garden, and an early fascination with birds' eggs.

Collecting birds' eggs was still commonplace in England then, though dying out rapidly (the practice is now completely illegal there, I hasten to add); and having received a small collection of blown eggs from a relative, a friend and I were inspired to fantasize about becoming great hero collectors in what would become an "Indiana Jones" mold — traveling the world having outlandish adventures as we collected the eggs of the most elusive of species and then sold them to museums and private buyers.

Our fantasies did not even take us as far as collecting a single egg ourselves, yet in my mind was sown the fascination of far-flung places and the thrill of encountering wonderful life forms. I was a naturalist first and foremost.

I have seen my own boyhood fascination with things natural echoed in young children around the world; there seems some innate empathy in children for other life, whether it is in snakes or tigers, and I find that deeply reassuring. However, the depth of my own interest in the natural world was largely dormant until I was exposed to the fledgling development in Britain of natural history programming on television.

As well, an unfortunate accident requiring regular treatment for a while in the nearest city came with a valuable reward, since it allowed me to get hold of one of the very first issues of Animals Magazine (launched in 1963, then relaunched in 1983 as BBC Wildlife Magazine) — at age 8. That was the first glossy natural history magazine I had ever seen.

Suddenly the natural world opened its arms to me and I was embraced. I was entranced by creatures whose names and lifestyles I rapidly learned, and my bedroom wall was to become a collage of wildlife images. Little did I realize then that many years later I would become a contributor to that magazine.

At the time I seemed an oddity, differing in my interests from those of my family. Later, at grammar school (high school), I became an outsider with an odd hobby, though such is the resilience of youth that I was undeterred by "not belonging" and was already making solitary forays into the local woods, along footpaths and across farmland in search of "nature."

I read my way through my school's library, with a strong fascination for adventure and nature, and it was there that I came upon the early writings of David Attenborough. My fascination deepened as I was drawn into his exploits around the world in search of wildlife long before he became a household name and TV presenter.

I never imagined that my own life would similarly involve me in traveling the world in search of wildlife and in the making of natural-history documentaries — and even allow me to meet the great man himself.

The second, concluding part of this feature will appear on this page on Dec. 19. Mark Brazil, naturalist and author, leads wildlife excursions worldwide and around Japan by land and sea. His latest book is "Field Guide to the Birds of East Asia" (A & C Black), while his earlier "A Birdwatcher's Guide to Japan" is also available. Copies are readily available through [email protected] or via his website at www.wildwatchjapan.com.