Today on New Scientist: 23 May 2012

The wider implications of a Greek eurozone exit

As Greece's future hangs in the balance, Europe should commit itself to securing the country's physical and mental health too

Greek crisis: How to prevent a humanitarian disaster

Economic catastrophe has left Greece facing a humanitarian disaster. New Scientist looks for lessons from previous financial collapses

Are street lights changing the balance of nature?

We all know light pollution hampers our view of the stars. Not many appreciate what it's doing under our feet, says Tom Davies

Fossilised ink sac gives up its melanin secrets

A dinosaur-era cephalopod defended itself by squirting ink just like that made by today's cuttlefish - this fossilised ink sac proves it

Crisis averted: Dark matter was there all along

Our cosmic neighbourhood contains no dark matter, according to a recent study. But a re-analysis suggests there's actually more of it than physicists thought

Getting hands on with Microsoft's new So.cl network

A mash-up of Pinterest, Facebook and even Google+, So.cl feels very much like Microsoft's attempt at a new social network - despite claims to the contrary

Artificial immune system gives baby vaccines a booster

The first 'all-human' model of the newborn immune system will help drive the development of baby-specific vaccines - which are seriously lacking

Win tickets to arts and tech festival NXNE in Toronto

We have a pair of five-day wristbands to Toronto's NXNE festival to give away. Is today your lucky day?

A dirty twist on beating the prisoner's dilemma

A cruel new strategy for the classic game-theory problem shows how exploitation can prove successful, but only if the exploited rolls over and takes it

Brain rewiring offers slim hope for obesity epidemic

Weight-loss surgery helps people to think thin, which could open the door to new and gentler drug treatments for obesity

Mixing art and science in Moscow

As science funding becomes a higher priority in Russia, there may be more room for artists in the lab too

Animal aviators: Unusual creatures take to the skies

Gliding is a skill many animals have mastered - even some that don't have wings. Meet six of the strangest

Change your stomach, change your brain

Weight-loss surgery cures food cravings. But it also makes some minds sharper, others duller. Find out why - from someone who's been through it

overeem laron landry mary j blige burger king islands joe flacco 2013 nissan altima masters par 3 contest