Despite bouts of illness, exhaustion, and threats from armed poachers, the pair were driven to complete the trek by their shared fierce determination to help document and preserve this territory and its wildlife. Nichols’ work captures a hidden world where forest elephants are glimpsed, fleetingly, through foliage, lowland gorillas bathe waist-deep in the cool water of marshy clearings, and chimpanzees stare in astonishment at a primate they very rarely see – man.

These images, together with Fay’s data, were enough to inspire the government of Gabon to protect a significant proportion of that country’s virgin rainforest from loggers, bush meat traders and ivory poachers by creating thirteen new national parks.

In this forest live elephants. Loxodonta cyclotis, a different species from the one on the sunny grasslands of East Africa – smaller and more furtive. They operate at close range in the understorey. If you annoy them enough, or frighten them a little, they will do their best to kill you, and their best can be very good.

In this forest live lowland gorillas. Painfully shy, pacific, vegetarian, explosive. Also in this forest live chimpanzees that haven’t learned fear of humans. They’ve been lucky so far, too remote to be shot and eaten. They’ll come towards you to ogle. In this forest live Pygmy peoples, Babanzélé, Bangombé and others, almost uninfected by outside culture. To say they love the dark woods and are happy to be there would be presumptuous, irrelevant and silly; it’s their world. In this forest live magnificently fat and quite poisonous snakes – Gaboon vipers – that make themselves invisible among fallen leaves. They’re patient. In this forest live red river hogs and skittish duikers and hornbills with noisy wings. Leopards too, although you’ll never see one. Ground-runner vines, thorny and mean, that make your feet bleed. Huge trees that drop weird, tasty fruit. In this forest lives the Ebola virus, somewhere, hiding unobtrusively within a reservoir species (a rodent? a bat?) during the intervals between its gruesome outbreaks among humans and apes. In this forest live spiders, rather large as spiders go, that you wouldn’t want to be surprised to find crawling on your neck. Sweat bees in blinding abundance. Termites that, in a night, can eat the floor of your tent. Crickets that George Lucas couldn’t dream up. Brigades and divisions of some of the planet’s most belligerent ants. Oh, and leeches, of course, they live here too. Giant centipedes. Giant moths. Dwarf crocodiles. Giant pangolins. All these and plenty more.

Michael Nichols was here to document (in images), as was I (in words), Mike Fay’s Megatransect Expedition, a wildly ambitious 2000-mile, 456-day trek. Both of us were on assignment to National Geographic magazine. But Nichols’ involvement was deeper than mine, his professional commitment broader. I was coming and going for snatches of the whole experience, no more than three weeks to a snatch; Nichols was devoting himself completely to the Megatransect, and also using it as a way to pursue his own long-term project of representing the look, the feel and the dynamic throb of Central African ecosystems.

Nichols and I enjoyed a conspiratorial sense of fellowship based on various shared convictions, including but not limited to these two: that Fay is demented, impossible, obdurate, aggravating, and the best of all people with whom to hike through an African jungle; and that this place to which Fay had enticed us – this great sweep of continuous forest and swamp and black-water streams and brown rivers, stretching from the northeastern border of the Republic of Congo to the southwestern coast of Gabon, and encompassing large portions of the Congo and Ogooué River drainages – is a uniquely spectacular and precious hunk of territory. When Nichols calls it “the last place on earth” without specifying last of what, I think I know what he means. Or at least how he feels. I think he feels that there’s just nowhere else, anywhere, anymore, not even the Amazon (which lacks charging elephants), that can match its pageant and scope of tropical wildness.

Feeling, not just thinking, is important here, because Nichols is a photographer who works from his heart and his gut, not just from his eye and that pink spongy organ behind it. Movement, tension, action – those are inherent in his work. He doesn’t compose pretty, tidy images; he’s more interested in vitality and flux. Events are happening, or about to happen, in his photographs, and when beauty is there it’s generally because beauty itself happened in some isolated, difficult spot. Ugliness often happens too. Change happens, remorseless and saddening; that’s part of the story. Another part is darkness and quietude. Within the forest, beneath its dense canopy, the light is dim (but not gloomy), and Nichols’ photographs capture that, intentionally. He honours the reality of this place in which light itself is a scarce resource.

Nichols takes risks, and not just physically. He trusts his audience – that’s you, the looker at these photographs – to let the eye linger while the imagination moves. What he cares about most are the reality of the moment and the power of the place. It seems very safe to say that his goal – unabashedly political, in its way, as well as artistic – is to make others care about the place and the moment too.

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