Next time you hear a starling sing, stop and listen hard. It may well be warning of a peril that endangers the whole world of nature - and the very future of the human race itself.

For scientists have found that gender-bender chemicals - increasingly contaminating the environment, our food, our water and our bodies - are having a bizarre effect on common birds, causing the males to give voice to longer and more complex songs.

This is only the latest in a long series of increasingly urgent alarms being sounded by wildlife against an insidious but devastating danger that threatens our children.

But so far our leaders have steadfastly and scandalously turned a deaf ear to them - and, even more shamefully, ignored the first signs that the peril is already affecting birth patterns, causing thousands of babies who should have been boys to be born as girls instead.

Starlings and their diverse, complicated and mimicking - though not beautiful - songs have long fascinated humanity.

Mozart was entranced by a starling after it copied a tune that the great composer was whistling in a pet store.

Modern scientists have discovered that starlings' songs contain similar patterns to human speech.

But if we could, indeed, understand what they are communicating, we would be wise to take heed.

Scientists at Cardiff University have discovered that the brains of male starlings foraging for worms at a sewage treatment works in South-West England have been subtly changed by being contaminated by oestrogen from the contraceptive pill and hormone replacement therapy (HRT).

The female hormones - present in women's urine, and passing through the sewage treatment unaffected - caused the part of the brain that controls their song to grow much bigger, causing them to sing at greater length and with even more virtuosity than usual.

The study confirms similar, if slightly differing, research on other birds, which scientists say is adding up to some of the first concrete proof of the effects of gender benders on the natural world.

Researchers at the University of California have found that feeding female finches with a hormone used in HRT has caused them to sing, something hitherto done only by their males.

And studies at the University of Alberta have found robins exposed to the pesticide DDT before birth suffered damage to the region of the brain that enables them to sing and protect their territory.

Dr David Crews of the University of Texas calls the research on birdsong "very significant", describing it as "the first step needed to demonstrate a causal link between specific pollutants and the effects on wildlife populations".

Yet there have been strange warning signs for decades. Way back in the early 1970s, researchers found that female gulls had taken to nesting together all over the U.S., the males having apparently lost interest.

When the bashful males were caught and examined, they were found to have developed female egg-laying canals.

In the 1980s, researchers in Florida found that alligators were failing to reproduce because their males had mysteriously tiny penises; further investigations revealed that they had developed female hormone patterns - and that turtles in the same waters had developed into hermaphrodites.

Most alarming of all, repeated studies by Britain's own Environment Agency have shown that about a third of the male roach in rivers and streams right across the country have begun producing eggs, after developing female sex organs.

Again, the problem was traced to oestrogen passing through sewage works - in some areas, near particularly heavy inflows of treated water, all the males were found to be between sexes.

The findings have inevitably raised concern that people may also be affected, since one-third of the country's drinking water comes from rivers, much of it beneath sewage outfalls.

And, whether or not this is the cause, male sperm counts have been dropping precipitously both here and across the world.


Studies in more than 20 countries have shown that average amounts have fallen by well over half in the past 50 years, from an average of more than 150 million per millilitre to 66 million.

The result is that men are now less than half as fertile as hamsters.

The counts are continuing to plunge by two per cent a year, and no end to the decline is in sight. At this rate, the average man will be unable to father children within decades.

Increasingly the sperm crisis is being blamed on a whole host of chemicals, not just synthetic oestrogen, but a wide variety of substances that have become ubiquitous in daily life.

They include the common plastic PVC; dioxins, the notorious pollutants found almost everywhere; PCBs, one-and-a-half million tons of which have been used in countless products from paints to plastics; and phthalates, universally used to make plastics more flexible.

Recent tests by WWF (formerly the World Wildlife Fund) on 14 basic foodstuffs taken from supermarket shelves found that every single one contained PCBs, and most were contaminated by phthalates.

Both substances have been shown to have deeply worrying effects on babies and children.

Scientists at Rotterdam's Erasmus University have found that boys born to mothers exposed to PCBs grew up wanting to play with dolls and tea-sets.

And research at the University of Rochester in New York State has shown that the male children of women exposed to phthalates have smaller penises and other signs of feminisation of their genitals.

Communities exposed to high levels of these and other gender-bender chemicals, from the Great Lakes of North America to the Russian Arctic, have been found to give birth to twice as many girls as boys.

This may offer a clue to the cause of a mysterious shift in the sex of babies worldwide.


Normally 106 boys are born for every 100 girls, in what is thought to be nature's way of compensating for the fact that males were more likely to be killed hunting or in conflict.

But increasingly this ratio is slipping - it is calculated that 250,000 babies who would have been boys have been born girls in the U.S. and Japan alone.

You would think that all this accumulating evidence would long since have sparked alarm in governments worldwide.

Far from it. When the EU drew up its first comprehensive controls on chemicals two years ago, it largely exempted gender benders from them.

Britain, under Tony Blair's leadership, was largely responsible for this exemption, and confidential documents show that it obediently acted to water down the controls following direct representations from the Bush administration - almost unbelievably putting the interests of foreign firms above the health of British children.

Since then, as Dr Gwynne Lyons, director of the expert group, CHEM Trust puts it, there has been "regulatory inertia".

That needs to change, and fast. If ministers continue wilfully to refuse to heed the science, they should, at least, listen to the starlings.