Washington, Apr 1 : Although April Fool’s Day is not an official holiday but plenty of pranksters and joke-lovers dupe friends and loved ones throughout the day. However, no one knows exactly when or how this tradition began.

It is believed that the day coincided with the coming of spring since the time of the Ancient Romans and Celts, who celebrated a festival of mischief-making. The first mentions of an All Fool''''s Day (as it was formerly called) came in Europe in the Middle Ages, reports Live science.

Washington, Apr 1 : Actor Vin Diesel must be regretting his appearing on Jay Leno’s show, for he was left red-faced after the talk show host grilled him on his marriage plans.

The Hollywood hardman appeared on ‘The Tonight Show’ with Leno on March 30, and the witty anchor made him answer the most personal questions on his relationship with girlfriend Paloma Jimenez.

The couple has been dating for seven years, and the actor has admitted that family members are putting pressure on him to propose.

London, April 1: In a new research, scientists from Oxford University have found that giant lions were roaming around Britain, Europe and North America up to 13,000 years ago.

According to a report by BBC News, the finding came in the form of the remains of giant cats that were earlier thought to be a species of jaguar or tiger, but after DNA analysis, they were proved to be lions.

The Oxford team analysed DNA from fossils and other remains gathered from Germany to Siberia, and Alaska to Wyoming.

Washington, Apr 1 : Adults who suffer chronic sleep problems are more likely to show suicidal tendencies than those without any insomnia complaints, a new study has found.

In the study, researchers found that the more types of sleep disturbances people had, the more likely they were to have thoughts of killing themselves, engage in planning a suicidal act or make a suicide attempt.

Washington, Apr 1 : A potential new HIV drug may one day treat patients who are not responding to Anti-Retroviral Therapy, suggests a new study.

Researchers, from Imperial College London, the National Cancer Institute, Bethesda, and Innsbruck Medical University, said when they used a molecule called D-1mT alongside Anti-Retroviral Therapy (ART) to treat monkeys they were able to reduce the levels of the simian form of HIV, known as SIV, in the blood.