Thursday, September 10, 2009

The Origin of Farming in Europe: Cultural Diffusion or Migration?

Ancient DNA Says Europe's First Farmers Came From Afar

Dogs and Infants make similiar errors, wolves don't

Like Infant, Like Dog
"The infants apparently believed believed adult instruction more than they believe their own eyes." Dogs behaved similarly.
Dogs: Kids in Fur Coats?

Erasing Fear Memories

Erasing Fear Memories
Memories of stressful events can be extinguished in young animals but are resistent to complete erasure in adults. New research hints at the neurobiological basis for these observations.

Photosystem genes in viruses

Photosystems at the double
Marine cyanobacteria viruses contain genes for both photosystems used in host photosynthesis.

Nano storage scheme which doesn't wear out

Nanotechnology: A gentle jackhammer
A futuristic method of data storage depends on the 'write–read' action of a multitude of tiny silicon tips. The concept of dynamic superlubricity offers a way to avoid the wear that would otherwise cripple them.

The History of Oxygen

Early Earth: Oxygen for heavy-metal fans
Chromium isotopes provide an eyebrow-raising history of oxygenation of Earth's atmosphere. Not least, it seems that oxygen might have all but disappeared half a billion years after its initial rise.

Sex Determination in Birds

Sex determination: Birds do it with a Z gene
The gene that determines sex in birds has eluded scientists for a decade. Now this all-important locus is revealed as a gene on the Z chromosome known for its proclivity for determining sex in all kinds of animals.

In mammals, males have XY chromosome pairs and females are XX, so the Y chromosome determines maleness and sex. In particular the SRY gene found on the Y chromosome determines testis.
In birds it's the other way around: males have ZZ chromosome pairs and females are ZW. However in birds the key gene is again for maleness and it resides on the Z chromosome.