ATLANTA,US:Scientists have discovered that all mammals urinate for roughly the same amount of time, regardless of their size.

A study carried out by researchers at the Georgia Institute of Technology in Atlanta found that animals of various sizes - from an elephant to a rat - take around 21 seconds to relieve themselves.

The team, who collated their findings using videos of animals going to toilet and combining them with data on mass, bladder pressure and urethra size, were able to come up with what they are calling the ‘law of urination’.

They were able to create a mathematical model of animals urinary systems and developed a theory as to why mammals take roughly the same amount of time to wee. Earlier studies failed to take into account urethra length and only considered the effects of bladder pressure.

The scientists compared the length of time it takes larger animals like elephants to urinate and compared it to smaller animals such as dogs and goats.–MN