Altruism may be a cunning form of selfishness - at least from a genetic point of view. This is the conclusion drawn by Samuel Bowles in a Science magazine report. The economics and behavioural science researcher in the US and Italy bases his theory on complex calculations, using genetics, climate and population data. He found that groups of early humans who co-operated by sharing - even in the face of harsh conditions and warfare - survived better than greedier groups, WebMD reports.
Cutting calories may extend lifespan because it appears to boost key infection-fighting cells in the immune system. In a 42-month study of rhesus monkeys at the Oregon Health & Science University, calorie restriction increased the lifespan of a range of organisms, from yeast to flies and rats, healthday.com reports. Long-term restriction had a 'remarkable effect on the maintenance of the [monkey's] immune system', says team leader Janko Nikolich-Zugich. The study focused on so-called T cells, which are crucial to the immune system and appear to be the most susceptible to ageing.
Diag-nose with smell
A simple smell test may provide early diagnosis of a range of mental illnesses, from schizophrenia to Alzheimer's disease. Studies by the University of Melbourne found that an abnormal sense of smell may indicate problems because such conditions typically affect the brain's frontal lobe, which is used to analyse and identify smell. Of 81 young people given 40 smells to match with a list of food odours, those who developed a mental illness had trouble identifying more than half, AFP reports.
Grey matter matters
British researchers say brain scans may be able to help predict schizophrenia, after a 10-year study of 200 young people at risk. Regular scanning showed early changes in the grey matter - brain tissue that transmits messages and helps store memories - of those who developed schizophrenia, BBCi reports.
Coming up short
The penis length of Indians is significantly shorter than average, with three out of five being at least 2.4cm less than international condom sizes, according to a study of 1,400 men by the Indian Council of Medical Research. Three out of 10 are 5cm shorter. Condoms have a failure rate of up to 20 per cent in India. 'While improper usage is one of the reasons, there is also slippage or tear, which is associated with the size of the condom in relation to an erect penis,' the council's Chander Puri told The Times of India.
Quit while you're ahead
Cutting down on cigarettes may not reduce the health risks, but it often leads to unexpected quitting, according to a University of Vermont review of 19 studies. In most of the studies, even many people who didn't want to quit gave up after cutting back on their habit, healthday.com reports.
Phone-cancer link rejected
The latest research into mobile phones - a 21-year study of more than 420,000 Danes - has found no link between phone use and cancer. The antennaes on mobile phones emit radio-frequency electromagnetic fields that can penetrate up to 6cm into the brain, WebMD reports, but the Danish Cancer Society studies 'found no evidence for an association between tumour risk and cellular telephone use among short- or long-term users'.
Jason Sankey is a tennis professional