Terence Blacker: One day, we may all look like Pete Burns

It is a shame the eminent Darwinian Professor Richard Dawkins has been spending so much of his time presenting the Channel 4 series The Root of all Evil? on which he makes the most rabid religious bigot seem quite sensible and restrained. There is more important scientific work to be done away from the cameras, and it concerns contemporary evolution.

Darwin showed that the way different species attract a mate - more melodious song, dazzlingly coloured sexual organs - has a profound effect on the way they evolve. Female shape changed among humans, Desmond Morris once told us, when we began to stand on two legs rather than four: breasts were essentially buttock-substitutes.

Now something entirely new has started to happen. Humans are bypassing the evolutionary process by changing the way they look with the help of the medical profession. The British Association for Aesthetic Plastic Surgeons has just reported that their members lifted, tucked, pinned, sucked or implanted 22,041 people during 2005, a 34.6 per cent increase on the previous year.

The usual saggy-bottomed huffers and puffers in the press will bemoan the fact that more and more people are paying good money and risking their health to change their shape or face, but, for the scientifically-minded among us, the trend raises more urgent questions. As time goes by, could perceptions of the normal and the attractive begin to change? Will there be a time when men expect the female breast to be as taut as a football, or when people's idea of an ordinary grandma will be a woman as eerily unlined as Anne Robinson? Will the fittest, in order to survive, need to avail themselves of the services of the British Association for Aesthetic Plastic Surgeons?

Already there are signs that cosmetic surgery is influencing the way we relate to one another. The comedian Joan Rivers would simply be unable to get away with her wonderfully vulgar comic routines if she had let nature take its course so that she became a conventional grandmotherly figure, all twinkly and wrinkly. If she had then gone on stage to make gynaecology jokes, it would have been deeply embarrassing, as if Dame Thora Hird had suddenly appeared with Rik Mayall and Ade Edmondson in Bottom. Comedy is afraid of age; the small number of entertainers who retain any kind of marketable sense of humour beyond the age of 50 would be advised to get themselves aesthetically enhanced, as Joan Rivers has done.

Even the untucked are beginning to have their perceptions twisted. I confess Pete Burns, left, the transvestite who minces about in hot pants on Celebrity Big Brother, has caused me to question my sexuality. The same features that at first seemed to be the result of a botched operationhave become oddly attractive. It is those participants who have been surgically lifted, inflated and tucked who have come to represent normality while the others, droopyand whey-faced, look out of place and distressingly human.

If the housemates were finches on the Galapagos Islands, there is no doubt whose genes would be passed down to the next generation - those belonging to the aesthetically enhanced.

Perhaps, as we evolve, the human race will come to look more like Anne Robinson or Joan Rivers and people will be born looking like Pete Burns. When natural selection begins to favour the unnatural, it is time for serious Darwinians like Professor Dawkins to study what is going on.

Never trust a man who plants trees

Last week, the surprising news was published that trees can occasionally harm the environment. But has anyone studied the psychological effects of tree-planting on humans?

The sudden appearance of newly planted saplings in a field or on the side of a road has, for some time, been a reliable indicator that something controversial - a new supermarket perhaps, or a Prescott housing estate - is about to take place.

The dark side of excessive tree-planting has been in evidence recently. Lord Heseltine appeared on TV to boast about the avenues he has been putting in, and, in an interview last weekend, the unpleasant developer and pal of Robert Mugabe, Nicholas van Hoogstraten, right, boasted that the 3,000 trees he had planted would secure his place in heaven. "When I get up there and they say, 'You're not coming in here', I can say, 'Well, what about all those trees I planted?'"

Watch out when new trees suddenly appear in your area. Someone in your neighbourhood may have something to hide.

* Recent events suggest that we are getting into something of a moral muddle about swearing. Over the past few days, Sir Alex Ferguson is said to have called a referee "a fucking cheating bastard" while the Observer editor, Roger Alton, told the Press Gazette that "for editorial to fuck up now would be entirely my own fault".

Meanwhile, 19-year-old Tom Jennings of Norwich has received a summons for a public order offence, "namely causing harassment, alarm or distress", having written a four-letter word on his skateboard. Let's hope that Tom has learnt his lesson, and now knows that you have to be a knight of the realm or a newspaper editor before that kind of behaviour is acceptable.