Getting Smarter Over the Generations

Wed, 11 Jun 2008 20:29:09 GMT

clipped by: dmegivern

Intelligence Quotient Rising Worldwide

Genetics, social conditions and culture all may play a part in the rise of human intelligence levels around the world. But the best method of determining why some people are smarter than others is still being debated.

For most of the last century it was widely thought that intelligence was in decline. The idea was that those at the lower end of the intelligence spectrum were having more children, thereby reducing the general intelligence level. Then one day in 1984, James Flynn, a New Zealand-based moral philosopher, had a Eureka moment that turned cognitive science upside down.

Flynn found that in both the developed and developing worlds, IQ had improved in the 20th century at the remarkable rate of three points per decade. This development has since become known as the ‘Flynn effect.’

One of the key environmental factors, Flynn says, is the adult-infant ratio: The more adults there are to children, the richer the cognitive environment.

Life discovered 4k underground

Thu, 21 Dec 2006 07:21:05 GMT

clipped by: nevercheer

Clip Source: www.newscientist.com

Gold mine holds life untouched by the Sun

The first known organisms that live totally independently of the sun have been discovered deep in a South African gold mine.

The bacteria exist without the benefit of photosynthesis by harvesting the energy of natural radioactivity to create food for themselves. Similar life forms may exist on other planets, experts speculate.

The bacteria live in ancient water trapped in a crack in basalt rock, 3 to 4 kilometres down. Scientists from Princeton University in New Jersey, US, and colleagues analysed water from the fissure after it was penetrated by a narrow exploratory shaft in the Mponeng gold mine near Johannesburg, South Africa. The shaft was then closed.

Uranium and other radioactive elements in the rock emit radiation that shatters water molecules, producing high-energy hydrogen gas that is able to cleave chemical bonds.

The bacteria exploit this hydrogen gas to turn sulphate (SO₄) molecules from the rock into hydrogen sulphide (H₂S). It is the energy-trapping equivalent of photosynthesis. The energy of radiation, which makes hydrogen gas energetic enough to form these bonds, replaces the energy of the Sun.

A study of the inert gases in the sample, such as xenon, show that the Mponeng water has been isolated from the surface for 20 million years, says Lin. This shows that the bacteria must live totally “independent from surface photosynthesis”.

Tags: science, life, underground, geology, biology, south africa

Clipmarks | dmegivern's Science collection

Getting Smarter Over the Generations

Intelligence Quotient Rising Worldwide

Life discovered 4k underground

Gold mine holds life untouched by the Sun