An instinct for discovery

Pathfinders, by Felipe Fernández-Armesto (OXFORD &pound;25 (428pp) &pound;22.50 (free p&amp;p) from 0870 079 8897) <br/> The Seventy Great Journeys in History, Ed. Robin Hanbury-Tenison (THAMES &amp; HUDSON &pound;24.95 (304pp) &pound;22.50 (free p&amp;p) from 0870 079 8897) <br/>Into the Abyss, by Benedict Allen (FABER &amp; FABER &pound;17.99 (274pp) &pound;16.50 (free p&amp;p) from 0870 079 8897)

The received history of exploration has always run as follows: Columbus and Vasco de Gama, fuelled by nationalistic ambition, a Renaissance curiosity about the world and good old-fashioned adventurism, kick-started a "golden age of discovery" that ran unbroken until the 19th century. In the process, the boundaries of the known world were extended immeasurably until the planet had been tightly girdled around, leaving slim pickings for any modern explorer today.

This model has been picked apart in recent years - and not just by the dawning realisation that the Chinese had already explored much of the world previously, before giving up out of boredom. The spread of Homo sapiens, now more clearly delineated by the analysis of mitochondrial DNA, reveals how the exploratory gene has always been a defining rather than a stray characteristic.

Expanding from Africa across Asia, it seems that man arrived as far as Australia long before venturing into the colds of Europe. This constant questing then resulted in the passage of the frozen Bering Strait c.15,000BC and a final descent down the Americas. The epic anthropological tale shows that we have always been as much restless hunter-gatherers as pastoralists - the "pathfinders" of Felipe Fernández-Armesto's magisterial account of explorers that followed over the next millennia.

Fernández-Armesto's recent history of The Americas showcased his outstanding ability to be both concise and bold, and this latest volume is no exception. He ranges from the achievements of the early Polynesian peoples in exploring the Pacific islands to the ancient Egyptian explorer Harkhuf, who brought back a pygmy for his boy emperor Pepi. One surprising point - when discussing how Arabian traders first sailed to India - is that "most would-be explorers have preferred to sail against the elements, actually avoiding a following wind, presumably because it was at least as important to get home as to get to anywhere new".

He suggests that just as such early traders made of the Indian Ocean "an Islamic lake", and Columbus occupied the Atlantic for the West, so the Arctic will dominate the last phase of the oceanic history of the world as it becomes a place of "commerce and cultural exchange" - aided, one is tempted to add, by the melting ice.

Much exploration has been done collectively by the human tribe as it inched incrementally forward. But there have always been a few individuals - always driven, sometimes dreamers and rarely easy for others to live with - who have pushed back the boundaries with a few bold strokes. Seventy Great Journeys in History includes the story of the admiral Zheng He, who left China in 1405 with a vast fleet of 63 junks and some 28,000 men. Over the next 30 years he travelled as far as Mecca and Africa, bringing back a giraffe for the Forbidden City.

The contributions to Robin Hanbury-Tenison's well-illustrated anthology are scholarly and well-chosen. While some stories, like Marco Polo's and Ibn Battuta's, are familiar, others are less so, such as the account left by Pytheas the Greek of a remarkable journey to Britain in 320BC, chasing amber, with tales of Iceland to the north.

Nor were all the journeys intended; Francisco de Orellana discovered the Amazon by accident. Starting near the source in Peru and unable to navigate back upstream, he emerged, surprised and weary, some years later on the shores of the Atlantic.

There is a long tradition of the explorer as mystic, seeking solace in the desert like St Anthony. It is to this tradition that Benedict Allen finds himself increasingly drawn, after 20 years of intense adventuring from the Amazon to Namibia and Papua New Guinea. Allen's latest book is a thoughtful reflection on the impulses that lie behind his restlessness. He quotes with approval Laurens van der Post's remark that what enabled him to survive hardships was "something inside that we may call upon to sustain us - something ancient, perhaps carried with us from our first home in Africa".

Allen returns to one of man's earliest and boldest strokes of exploration: the crossing of the Bering Strait by the occasional ice bridges that form between Russia and Alaska, less easy now than in more glaciated times. Over the years he has compiled a list of guidelines for exploring success (on paper now "discoloured by the ochre sands of the Kalahari, buffed by the winds of the steppe, stained by Amazon fungi and dappled with blood"). Top of the list is the choice of companion, human or animal. The affection that Allen feels for the ice dogs who guide him is palpable, even when they lead him over the edge of the tundra and into the titular abyss.

He reminds us that domesticated dogs accompanied the first men on their crossing, as they did the Inuit, who originated in this area of Russia before making their own circumnavigation of the globe, spreading around the Arctic Circle as far as Greenland. That journey, made between 3,000 and 2,000BC, was as remarkable as anything that the Egyptians were building at the time.

His own journey is at times a traumatic one, not least because he patently fails to observe his own guidelines. He finds himself in that existential dark place that comes from extreme moments of survival, when what Shackleton called the "naked soul of man" is reached.

Allen's tale illustrates perfectly that the explorers' task is far from completed. Over the last half-century, the world's highest mountains have been climbed and the North Pole reached on foot, to say nothing of journeys to the moon. Yet there remain plenty of unexplored corners of our planet to be met with a wild surmise: the ocean floor, Eastern Himalaya and the Amazon will all be capable of surprising us in years to come. More familiar territory can still be revisited with an open mind. There is still much to discover; the only fetters are a lack of imagination, and the dangerous presumption that there is nothing left to find.

Hugh Thomson's 'Cochineal Red: Travels through Ancient Peru' is published by Weidenfeld & Nicolson