Matt Ridley is the author of provocative books on evolution, genetics and society. His books have sold over a million copies, been translated into thirty languages, and have won several awards.

In my book I point out that an unemployed British father of three on welfare today receives more in state support than a man on the average wage received in income in 1957. It's an eye-catching reminder of how wrong J K Galbraith was to argue that affluence in the late 1950s had already gone too far.

Now the Institute of Fiscal Studies has compiled data on average incomes in Britain since 1961, coming to the remarkable conclusion that

in real terms the bottom 25% are now considerable richer than were the top 25% in 1961.

In my book I quote the English environmentalist Jonathon Porritt as follows: 'It's blindingly obvious [that] completely unsustainable population growth in most of Africa will keep it permanently, hopelessly, stuck in deepest, darkest poverty.'

At first I had assumed that the quote, which I had found in another book, must be out of context. Surely nobody would say anything so foolish or so heartless. Surely he was caricaturing some blimpish view from a reactionary? So I looked up the original article, in The Ecologist in 2007, to be sure I was not being unfair to quote him thus. You can read the whole article here. Here's the longer context of the quote.

Yet the facts speak for themselves: the fewer there are of us, the greater our personal carbon budgets - and just remember we're starting from a baseline here in the UK of around 12½ tonnes of CO2 per person!I can't tell you how politically incorrect it is to spell things out in those terms. Even those who are getting more and more enthusiastic about the idea of personal carbon budgets (including Environment Secretary David Miliband) wouldn't dream of giving voice to such a crass calculation. Leaders of our ever-so-right-on environment movement can barely bring themselves to utter the dreaded "p" word. The Millennium Development Goals don't mention population. Tony Blair's Commission for Africa ignored it entirely, even though it's blindingly obvious that completely unsustainable population growth in most of Africa will keep it permanently, hopelessly stuck in deepest, darkest poverty. Our very own Department for International Development grits its teeth and reluctantly doles out little bits of money for family planning projects, but the idea that it should be the Department's No 1 priority - if it was remotely realistic about its poverty alleviation aspirations - remains anathema to most officials and ministers.

There's a lot of debate about the `Medieval Warm Period'. But I've always been intrigued by the warm period of 7,000 years ago, known as the Holocene Optimum, and I have been doing some digging to find out just how warm it was. I've come away rather amazed.

Have a look at this image, which uses stalagmites in caves to estimate ancient temperatures (as graphed by Wilis Eschenbach)

The Globe and Mail (Toronto) has made a nice new version of my "handaxe and mouse" image to illustrate their review of The Rational Optimist

Tim Black has an excellent article in Spiked about the hypercautious European reaction to the Icelandic volcano in April:

We have sincediscoveredthat the maximum density of ash (100 micrograms of ash per cubic metre) over the UK during the ban was one fortieth of that nowdeemeda safe threshold (4,000 micrograms of ash per cubic metre). In other words, the ban was nowhere near justified by what is now the official threshold.

He goes on to give some remarkable numbers from the similar over-reaction to avian flu:

Listen to my interview on NPR's Leonard Lopate Show

and an MP3 of my interview on PM with Marc Colvin, in Australia

My good friend Dave Sands is not only a brilliant biologist -- I cite him in The Rational Optimist arguing for genetic modification to improve the quality rather than the quantity of food -- but a very fine poet. He's profiled in yesterday's New York Times discussing his latest theory that ice-forming pseudomonas bactera in the air play a central role in precipitation:

In the last few years, Dr. Sands and other researchers have accumulated evidence that the well-known group of bacteria, long known to live on agricultural crops, are far more widespread and may be part of a little-studied weather ecosystem. The principle is well accepted, but how widespread the phenomenon is remains a matter of debate.

If true, this could have all sorts of implications.

One small fact in my book has caught several readers' attention:

Today, a car emits less pollution travelling at full speed than a parked car did in 1970 from leaks.

My source for this remarkable statistic was Johan Norberg's 2006 book När människan skapade världen. In a translation he sent me it reads:

nterview in the Guardian today:

"If people are all the same underneath, how has society changed so fast and so radically? Life now is completely different to how it was 32,000 years ago. It's changed like that of no other species has. What's made that difference? Clearly our genes haven't changed; this process has happened far too fast for genetic change. My answer, bringing together my evolutionary knowledge and a lot of economic reading, is this: sex is to biology as exchange is to culture."

Here is why Craig Venter's new organism carries absolutely no fears for me: the Red Queen. Evolution is a treadmill.

People speak about artificial life forms getting loose and running amok. But that's not how life works. It's a jungle out there.

Nature is continually trying new life forms on a truly gigantic scale and testing them against each other. Very few get to take over the world even briefly and even they soon succumb to evolving predators, parasites and competitors.

John Tierney reviews The Rational Optimist in today's New York Times:

Every now and then, someone comes along to note that society has failed to collapse and might go on prospering, but the notion is promptly dismissed in academia as happy talk from a simpleton. Predicting that the world will not end is also pretty good insurance against a prolonged stay on the best-seller list.

The Sunday Times printed an edited extract of the book on 16 May.

People love to talk about the energy industry in voices of gloom and doom. The oil's running out, the lights are going out, the pollution's getting worse. But pause to consider the good news. Like shale gas.

Over the past decade, a wave of drilling around the world has uncovered giant supplies of natural gas in shale rock. By some estimates, there's 1,000 trillion cubic feet recoverable in North America alone-enough to supply the nation's natural-gas needs for the next 45 years. Europe may have nearly 200 trillion cubic feet of its own.

Imagine a source of energy...

As own goals go, this was a stunning shot.

The quantity of cereals harvested in the world has trebled in 40 years [correction: nearly trebled in 50 years!], but the acreage planted to cereals has hardly changed at all.

(graph from my book)

My good friend the evolutionary biologist and expert on old age, Tom Kirkwood, has made a splash in my local newspaper, The Newcastle Journal, by writing to all three British party leaders to ask them to emphasise the positive rather than the negative aspects of people living longer.

Our studies are revealing high levels of capability and good quality life among people who are well into their 80s. They are not all in poor health needing high levels of care. Indeed, many view their health as 'excellent' and still live highly independent lives.

I point out in The Rational Optimist that the average lifespan has increased by a third during my lifetime; life expectancy is increasing globally by 5 hours a day. Kirkwood's Changing Age Charter, like my book, says:

The oil spill in the Gulf of Mexico is a horror, for people and for wildlife. It will surely cause huge damage. It is a reminder that for all the talk of global impacts, the worst environmental crises are still local ones.

But it is worth pausing to reflect how rare such terrible oil spills have now become. Here is the data on world tanker spills over the past 40 years: