Bear-baiting was banned in 1835, but it appears that dinosaur-baiting is still considered public entertainment. What other excuse could the BBC have for a full-length interview with Jurassic joker Jim Davidson?

Last year, Davidson returned from the showbiz desert (aka Dubai) to appear in Hell's Kitchen. ITV stuck him in a sweat- box with the Big Brother winner Brian Dowling and waited for the media storm to break, which it did when he said “shirt-lifter”. More than reality TV, this was celebrity morality TV, designed to make us feel superior to the baited beast. Last night BBC One unearthed Davidson's fossilised remains for The Dark Side of Fame with Piers Morgan. Once more the idea was to goad him into being offensive, so that viewers could feel smugly shocked.

Davidson, a South London boy, escaped his “shitty life” via ITV's New Faces talent show (second to Nookie Bear in 1976). For anybody unaware of how normal his jokes about blacks were back then, there was an old clip of uncle Bob Monkhouse rocking with laughter at Jim's “Chalkie” routine. In the 1980s Davidson became a hate figure to “alternative” comedians. The BBC made him a gagged family gameshow host, until Pop Idol put his creaky Generation Game out of its misery. By now Davidson was famous largely for his drinking, drugs and marital break-ups.

Morgan's thesis was that “Britain changed but he didn't”. Yet Davidson's performance suggested he had learnt some new tricks. Through rehab and the 12 Steps programme, the old binge-whinger has picked up the language of victim culture. So he blamed not his parents but his biology, claiming that he was born an alcoholic, and that this and womanising are symptoms of uncontrollable “person-ality disorders”. He also blamed the Mirror under Morgan's editorship for ending his fourth marriage, because they revealed an affair to his wife: “The media did it. I wouldn't have told her.”

While Davidson played his scripted part in this grim celebrity morality play - talking about doing cocaine in bed with two birds then crawling home to his wife and baby, complaining that “we just get to like black people and they make them f***ing traffic wardens” - Morgan tried to occupy the moral high ground with a straight face. At the end he admitted, with agonised expression, that: “The worst thing of all is, you still make me laugh.”

Davidson never made me laugh even in the 1970s, when we called the one black lad in our Surrey village Chalkie. I might be one of the “lefties” Davidson despises, but I appreciated Bernard Manning as the best comic in Britain. Davidson wasn't even the best on Big Break. Comedy history shows that it is quite possible to be both offensive and funny - but one does not necessarily lead to the other. Davidson told Morgan that the “bottom line” with Dowling “wasn't the fact that he was gay, it was the fact that he was an a***hole”. The bottom line with Jim wasn't that he was racist or homophobic. It was that he was an unfunny a***hole.

Neither did I expect to like Bruce Parry, star of Tribe and now Amazon. He looks like a Green creeping Jesus. But I warmed to him somewhat, as the indigenous peoples he visits do, because he doesn't preach at them.

Parry's trek along the Amazon began in a cocaine-producing region of Peru, where the realities of life are far removed from the black-and-white cartoons of the West's “war on drugs”. He met alpaca farmers descended from the Incas, Roman Catholics who make offerings to a fertility goddess and drink coca tea while their boy - a natural for Peru's Got Talent - dances around. Parry pronounced that “life is good in the high Andes”, but they insist it is not good enough for their children. Their daughter was visiting the family hut from university - where, rather disappointingly, she studies anthropology.

Down the mountain small farmers like Antonio grow coffee and cacao but make more money from coca. Yet Antonio expects barely $100 for his coca harvest - the price of a gram of coke in London. Parry visited a squalid jungle site where peasants mix coca leaves with bleach, kerosene, and sulphuric acid then send the paste to be processed into white powder. The police commandante refused to use their US-bought helicopter gunships to eradicate coca crops because the locals would revolt. Meanwhile, in the former stronghold of the Maoist Shining Path guerrillas, villagers arm themselves against land-grabbing drug gangs and cattle ranchers because “we don't want to live as we did in the past”.

Fascinating and potentially addictive stuff. I could have hit Parry with a tool when he described women and children digging hard ground with machetes as “really lovely”. More sensibly he concluded that the politics of the war on drugs made it all “a swirling mess .... I don't have any answers”. Nor does anybody here, it seems. But it might be a start to give these people something more to live on than subsistence coca farming, and to provide something more fulfilling than coke as an escape in the West, for young clubbers or old comedians.

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