After 34 years, I have finally officially become a man. This momentous event happened during an Amazonian tribal ritual in which I endured pain that’s reputed to be worse than 100 bullets. Well, I say I endured it — actually, I cried like a stuck piglet for three whole hours.

I have just returned from the jungles of the Brazilian Amazon, where I’ve been shooting a wildlife documentary for Discovery Channel. Called The Venom Hunter, it essentially involves me finding as many peculiar poisonous animals as possible, while living with the tribes that use, or are abused by, their toxins.

Away in those forests, far from roads or towns, the critter-catching was unrivalled. A green-striped vine snake slithered along my arm, her tongue flickering as though she was waving a fan in my face. There were glass frogs at the water’s edge, their transparent bellies revealing their internal organs, complete with beating heart. And Brazilian wandering spiders, the world’s most venomous arachnids, with a bite whose side effects include a three-day erection — which might sound ideal, except that the sufferer may be left impotent.

Processionary caterpillars, adorned with ludicrous spiky haircuts, travelled in nose-to-tail wagon trains, and a skeleton tarantula crouched in the entrance to her burrow, with perhaps 30 spiderlings clustered around her — they poured back into the hole like quicksilver when we walked by.

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BACKGROUND

• Pure shores of Brazil's Bahia

• Brazil's wild wetland

• Is it safe to take internal flights in Brazil?

• Making friends in Rio's B&Bs

Before we could leave the rainforest, one vital job remained. I had to be stung by a bullet ant. In the initiation rite to come, I would be thrusting my hands into a pair of gloves with about 400 of these creatures woven into them, so it was essential to find out whether I was allergic to their sting.

This may seem weird — after all, back home an ant is just a good way to spoil a picnic. But here in Latin America, they can be evil. Bullet ants are the largest on the planet, almost as long as my little finger, and their sting is scientifically proven to be the most painful of any invertebrate — 30 times more agonising than that of a common wasp. Their name is all the warning you need.

We found an ant and placed her on my arm. She pulled her abdomen back and plunged in her 5mm stinger. The pinprick was not palpable, and there was no pain for at least a second. Soon, however, there came a terrific burning sensation, which grew and expanded as the venom spread. Perhaps two minutes after this, the scorpion-like neurotoxin kicked in. I started to shake all over, as if I’d drunk far too much coffee and was hugely overstimulated.

There was worse to come — from our medical support team. I wasn’t allergic to bullet ants, they said. The sting was supposed to feel that way. . .

THE MAIN transport on the Amazon is a fleet of beautiful, chugging boats, which look like St Louis paddle steamers, but without the big hamster wheel. Inside, colourful hammocks

are strung side by side, and passengers while away the days, chatting, smoking and gambling. We took a tributary of the mighty river to find the Satere-Mawe, the tribe who practise the bullet-ant ritual as a trial by pain. As well as conferring maturity, they believe that it protects them from disease and makes them better hunters.

Their village is a stunning place, with white-sand beaches at the riverside and palm-thatched buildings under mango and papaya trees.

The people, though, are even more beautiful. Their hunter-gatherer community is little influenced by the outside world, and they are extremely fit and healthy, wanting for nothing at all. We never saw a face that wasn’t smiling — the plentiful fish and fruit

mean they scarcely need to work, and can spend hours of every day playing with their children or — this being Brazil — contesting fiercely competitive football matches.

After just a few days of learning their way of life and winning their trust, I felt more at home than I think I ever have. The kids were crawling all over me as if I were a much-loved uncle; the adults doted on me like a favoured (if slow-witted) son.

By now, I’d wound myself up into a tizzy about the ritual to come, but there was no way I was going to back out and let down my hosts. The ant mittens may seem like a pretty barbaric piece of kit, but here the rite was a communal thing, with the entire village supporting the young men in their decision to take part, while not pressuring them at all. When you compare it with the many selfish and stupid ways in which young men choose to prove themselves in the developed world, this makes far more sense.

Most of the other initiates were in their mid-teens, but the guy I was lodging with — my age, and already a fast friend — decided at the last minute to go through it for a second time, to show solidarity with me. Talk about lump-in-the-throat time.

The first phase in the ceremony was to get inked.

The village artist painted tattoos all over my body with deep-blue plant dye, while the entire community stood around shouting advice. I couldn’t understand a word, but I ended up covered, with a scorpion on my shoulder — it looked like a deformed lobster — and a huge ant on my back.

The next day, we went out to collect the ants. We stuck soft palm fronds into their nests, and, once the ants had grabbed them with their huge serrated mandibles, we extracted them one by one, transferring them into a bucket that contained a sort of natural chloroform to knock them out. While seeing stars, they were woven into the gloves, giant jaws on the outside and scary stings on the inside. About 400 of them.

I don’t know how to describe the ceremony itself. It certainly makes unsettling viewing to see people going through that much pain, but it’s gripping stuff. I was the third man up to take the test. The younger guys before me hadn’t made a sound, but were now back in the line, slumped in the arms of soon-to-be initiates and slipping in and out of consciousness.

Everyone was dancing and chanting, and the jungle itself seemed in sympathy with proceedings. A full-on rainforest cloudburst bounced gallons of water off the mud. Lightning crackled across the skyline.

I put my hands into the gloves. Actually, it wasn’t that bad: pretty unpleasant, but bearable; just like the single sting, but repeated over and over again. I stuck it out for the full 10 minutes, then removed the gloves and danced on until all the other initiates had been through the ordeal. Then my crew took me out of the line-up and off to get some medical tests done, to quantify what the venom was doing to me. That’s when things started to go wrong.

Unlike many powerful neurotoxins that are designed to paralyse potential prey, the bullet ant’s sting has evolved over the millennia as a tool for defence. At a biochemical level, it prevents the body from protecting itself against pain, sending the neurones into free flow and creating escalating agony, designed to make any inquisitive animal think it has suffered enormous physical damage — and clear off.

I had suffered several hundred stings, and all of a sudden I went beyond pain. The sensations are not describable using simple words or metaphors, so I’ll just try to describe how I reacted.

First, I started wailing, then, once that had passed, the floodgates opened — deep, guttural sobbing, uncontrollable shaking, writhing, convulsing. You could see the neurotoxin kicking in, my muscles starting to palpitate, my eyelids becoming heavy and drooping, my lips going numb. I started to drool, and suddenly I wasn’t responding to anything at all. My legs wouldn’t hold me up, and our doctor was shouting at me to keep moving and not to give in to the urge to lie down and let it take me.

If there’d been a machete to hand, I’d have chopped off my arms to escape the pain. The other boys were in a similar state, but, interestingly, my host, who had been through the ritual before, seemed far more in control.

It took three hours for the pain to ease a little, and shortly after that I was back playing footie with the kids — though with a hand clasped in each armpit and a pause every few minutes to scream a bit. Twelve hours later, my hands were swollen up like inflated washing-up gloves. If I pressed a thumb into them, it took two minutes for the impression to disappear from the fluid-swollen flesh.

Now I am back in a posh hotel in Manaus, my indelible face and body decoration drawing quizzical looks. But, since I am now officially an adult, and can purchase beer, wear long trousers and appreciate subtitled movies, I’m sure it was worth it.

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