A new study challenges the popular idea that sexual cannibalism occurs because a female is unable to alter or 'tone down' her aggressive mindset after foraging and hunting for prey. Instead, females are sexually cannibalistic because they are testing the males, rather than just being inherently aggressive, says University of Melbourne scientist Dr. Mark Elgar.

In the first trial, 11 of 16 female raft spiders (Dolomedes fimbriatus) that copulated then attacked the males during or immediately after copulation. But only four attacks were fatal.

Mariners have long spoken of 'walls of water' appearing from nowhere in the open seas, that is why freak waves are called freak waves.

Oceanographers have disregarded such stories and instead suggested that rogue waves - enormous surface waves that have attained a near-mythical status over the centuries - build up gradually and have relatively narrow crests, but new research says rogue (or freak) waves can emerge suddenly, being preceded by much smaller waves. At least in mathematical models published in Proceedings of the Royal Society A.

Poisonings from recreational drug and alcohol use account for 9 percent of all poisoning-related hospital admissions,while males and people under 30 are at greatest risk, according to a paper in Drug and Alcohol Dependence.

The lesson: Young people are more inclined to be both experimental and stupid about it, especially at Australian music festivals. The report is based on 13,805 patient records collected between January 1996 and December 2013 using data from the Hunter Area Toxicology Service (HATS). The report finds that stimulants were the drug class most commonly linked to recreational poisonings, followed by alcohol, opioids, sedatives, hallucinogens, cannabis, non-narcotic analgesics, ecstasy and cocaine. 

An analysis of data gathered from 14 independent studies indicates that the influence of genes on intelligence varies according to people's social class in the US, but not in Western Europe or Australia. The findings are published in Psychological Science, a journal of the Association for Psychological Science.

Research suggests that genes and environment both play a critical role in shaping a person's intelligence. A longstanding hypothesis in the field of behavioral genetics holds that our potential intelligence, as set by our genes, is more fully expressed in environments that are supportive and nurturing, but is suppressed in conditions of poverty and disadvantages. While some studies have provided evidence supporting this hypothesis, others have not.

Multiple sclerosis (MS) may be triggered by the death of brain cells that make myelin, the insulation around nerve fibers, according to research on a novel mouse model developed by scientists from the University of Chicago and Northwestern Medicine. The death of these cells initiates an autoimmune response against myelin, the main characteristic of the disease, which leads to MS-like symptoms in mice.

This reaction can be prevented, however, through the application of specially developed nanoparticles, even after the loss of those brain cells. The nanoparticles are being developed for clinical trials that could lead to new treatments in humans.

The greater proportion of women than men on college campuses may contribute to a hook-up culture where women are more willing to engage in casual sex and are more aggressive toward other desirable women who are perceived as rivals, according to new research published by the Society for Personality and Social Psychology.

In the first experimental study to examine this issue, researchers found an imbalanced gender ratio affects views about casual sex for both men and women in ways that people may not consciously realize.