Men with longer ring fingers face a lower risk of dying from Covid-19 and are more likely to suffer mild symptoms, researchers claim.
Academics found coronavirus death rates in countries where men have shorter ring fingers were up to a third higher.
Ring finger length is determined by how much testosterone a foetus is exposed to when growing in the womb, the experts said.
The more testosterone a male is exposed to in the womb, the longer their ring finger will be, it is believed.
Testosterone is thought to be protective against severe Covid-19 by increasing the number of ACE-2 receptors in the body.
Scientists believe the coronavirus, officially called SARS-CoV-2, enters the body and causes infection through these receptors.
But studies also suggest that high levels of ACE-2 receptors can protect against lung damage, which the coronavirus can cause.
The new study, carried out by Swansea University, found men with l