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The fossil record seems to indicate that the diversity of marine creatures increased and decreased over hundreds of millions of years in step with predator-prey encounters. For decades, there has been a debate between paleontologists, biologists, and ecologists on the role of ecological interactions, such as predation, in the long term patterns of animal evolution.

A new technique which enables us to identify faces more accurately could make security systems more reliable. Humans are very good at identifying faces we know. However, researchers said, we are much less accomplished when the face is unknown to us. This is almost always the case with the faces captured by CCTV cameras or used to check at a passport barrier.

Psychological factors can make people more likely to suffer physical illness, but cognitive behavioural therapy can help sufferers manage their condition. "People often pigeonhole diseases as being biological or psychological, but in fact they're often a complex mixture of both," according to a researcher. She and her colleagues studied 1000 people who contracted either glandular fever or food poisoning. They wanted to see who would go on to develop irritable bowel syndrome.

The drug tadalafil appears to improve erectile function in men with spinal cord injuries, according to a new article. Between 10.4 and 83 individuals per million worldwide experience spinal cord injuries every year, according to background information in the article. Only 25 percent of men with spinal cord injuries are able to have erections that are adequate for having intercourse.

Researchers provide new details about the inner workings of a parasitic worm that causes a tropical disease called schistosomiasis, which leads to itchy skin, fever, chills, muscle aches, and liver disease that, in some cases, can be fatal. The new results may help design drugs or vaccines against the disease. Schistosomiasis, a disease affecting up to 200 million people in Asia, Africa, and South America, is spread by parasitic worms called blood flukes that live in fresh water. The worms enter the human body through the skin and move to either the large intestine, small intestine, or the bladder.

Scientists may have solved a discrepancy between the number of extremely small, faint galaxies predicted to exist near the Milky Way and the number actually observed. In an attempt to resolve the "Missing Dwarf Galaxy" problem, two astronomers used the W. M. Keck Observatory in Hawaii to study a population of the darkest, most lightweight galaxies known, each containing 99% dark matter. The findings suggest the "Missing Dwarf Galaxy" problem is not as severe as previously thought, and may have been solved completely.

Health professionals are regularly confronted by men's complaints that condoms do not fit, or that they are uncomfortable. Correct condom use is critical for preventing unwanted pregnancies and the spread of sexually transmissible infections, yet a new study found that study participants who reported problems with the fit and feel of condoms were also among those who reported the highest rates of condoms breaking and slipping.

A fitness expert encourages her personal training clients to break their more ambiguous goals of say, feeling better or dropping a few dress sizes, into smaller goals that can be achieved in three to four weeks. She discourages weight-oriented goals because weight loss is a long-term process and everyone loses weight at different rates. Instead, she wants to know how her clients feel. She is a big fan of small steps and a forgiving temperament. If a goal is not met, she said, it should be reassessed to make sure it's reasonable and then sought after again -- after a brief break.

Significant sexual problems often are an unexpected -- and unwelcome -- side effect of the treatment of early-stage cervical and endometrial cancer for many women following hysterectomy. A targeted therapeutic approach involving mindfulness training has been found to improve desire, orgasm, arousal and other aspects of sexual satisfaction in just three one-hour sessions.