Monthly Archives: September 2013

Population Control

The jury is out on whether the global population will reach 10 billion though there seems little doubt that our planet cannot sustain the current population, never mind 10 billion, with a Western life style.  Maybe some of you saw Stephen Emmott’s show ‘Ten Billion’ at London’s Royal Court Theatre last year; I didn’t but you can read his book of the same title.  As you will probably have guessed from the title, he thinks we are headed for a global population of 10 billion and that radical social and political action is needed because science and technology cannot avoid the impended disaster.  Erle C. Ellis does not believe that overpopulation is problem because he subscribes to Ester Boserup’s theory that population growth drives land productivity.  He suggested in the New York Times last week (13th September 2013) that we have transformed ecosystems to sustain ourselves in the past and will continue do so.

This idea could be extended to suggest that the human society or population is self-controlling that has parallels with the Gaia principle that the planet is self-regulating system in which organisms co-evolve with their environment.  The UN low-fertility model offers some evidence of self-regulation of the human population being to operate because it predicts the global population reaching a maximum of 8.34bn in 2050 and declining to 6.75bn by 2100.  At those levels engineering solutions could probably manage the rest and avert disaster.  Danny Dorling in his book ‘Population 10 Billion: The Coming Demographic Crisis and How to Survive It’ provides further evidence by pointing out that the global average family size has never been so small with the norm being less than one child per woman for more than half the planet and immigration to wealthier countries leading to further declines in birth rates.  If the UN low fertility model is right then perhaps we will be able to avoid overpopulation but  scientists and engineers will still need to redouble their efforts to provide sustainable goods and services.  Progress is being made but mainly through incremental improvements that many of us take for granted perhaps in part due to our ignorance of science and engineering or at least of the advances in living standards that it are being delivered to billions of people who previously did not access to the internet, mobile phones and medicines.


‘Overpopulation is not problem’ by Erle C. Ellis in the New York Times on September 13, 2013 (

‘Crowded Planet’ by Clive Cookson in the Financial Times on July 13/14, 2013

‘Population 10 Billion: The Coming Demographic Crisis and How to Survive It’ by Danny Dorling, published by Constable

’10 Billion’ by Stephen Emmott published by Penguin,,9780141976327,00.html

‘Damn the cynics and embrace the positive’ by Luke Johnson in the Financial Times on August 14th, 2013 or


Stonemasons and skateboards

skateboardWalking through campus last week I saw a stonemason carving small chamfers every 30cm or so around the edge of plinth being prepared to receive a new sculpture.  A few days later there were metal tabs fitted in the chamfers, presumably to discourage skateboarders from using the plinth for acrobatics.  These metal tabs are becoming as common in our public places as the skateboarders they are designed to discourage.  I can understand old people being worried by fast moving youngsters on skateboards, but the speed and freedom of movement is part of the attraction for young people.  As a teacher of engineering, I see the skateboard as another everyday example of engineering with which to liven up the classroom and grab students’ attention.  Try riding a board into class to engage attention!

Below is a ‘5E’ lesson plan for beam bending theory based around a skateboard.  For more on Everyday Examples in Engineering ‘Bridging Cultures’ on June 12th, 2013; and ‘Disease of a Modern Age’ on June 26th, 2013.