You can now find out whether you are an early bird or a night owl - thanks to scientists at Swansea University, who have discovered a new "non-invasive" technique of identifying people's sleep patterns.
Researchers from the School of Medicine at the University tested the method - simple mouth swab - at Cheltenham Science Festival to identify their natural pattern of wake and sleep - known as the circadian rhythm.
The team said that instead of blood samples that were required to obtain the ribonucleic acid (RNA) needed for this type of research, all that is required now from the subject is a quick cheek-swab, reports BBC.
"The novel technique we have developed at Swansea is entirely non-invasive, so we can use it at a public event," explained Sarah Forbes-Robertson, Research Fellow at the School of Medicine, Swansea University.
"Previously you needed to take blood samples to obtain the RNA (ribonucleic acid) needed for this type of research. Our technique allows us to get a useable sample just by swabbing the inside of an individual's cheek," she added.
A number of different genes control an individual's natural circadian rhythm. The levels of RNA produced by these different genes indicate how active they are at different times of day.
One gene known as Per2 produces the highest levels of RNA at around 4am, and is the gene associated with sleep, researchers said.
The gene examined at Cheltenham Science Festival, which produces its highest levels at 4pm, known as REV-ERB, works in opposition to Per2 and is thought by researchers at Swansea to be associated with wakefulness.
Forbes-Robertson said if a person produces higher levels of REV-ERB before 4pm, they are likely to be "an early bird". If someone produces higher levels after 4pm, they are likely to be a "night owl".
The team now plans to use the technique to study various conditions such as Attention Deficit Hyperactivity Disorder (ADHD) to see if they are linked to disturbed circadian rhythms.