A survey sought the replies from nearly 2000 people on some of the possible answers to a list of quirky scientific queries.
It was found that 'Why is yawning infectious? What came first, the chicken or the egg? And why does hair turn grey?' were the top three popular quirky science queries, the Mirror reported.
Professor Chris Smith, of Manchester Met University, unopened the mystery behind contagious yawning, saying that it is a result of increased levels of carbon dioxide in the lungs, therefore if in a group are all relaxing together, it is probable they'll all reach the same elevated level of CO2 at approximately the same time.
Thus, the first chicken would have hatched from an egg laid by a "chicken ancestor". So the egg came first.
It was also revealed that hair colour is the result of pigment secretion and it gradually turns gray as the secretion stops with aging.
Researchers at University College revealed that laughter is infectious because the sound of laughter activates the premotor cortical region; the part of our brain that readies our facial muscles to react to sounds and this in turn makes us smile.
However, if you try to stimulate laughter in the wrong situation, others do not join in.