It is a fun guide to knowing how old our dogs are, but the 1:7 ratio was never intended to be scientific.
A study in the States has buoyed several other studies by revealing why we cannot rely on the custom to accurately identify how old a dog is when compared to a human.
Notwithstanding the fact that dogs of different breeds have different lifespans, a dog ages in a different way from humans. The study – carried out by the San Diego School of Medicine – uses genetic and chemical markers at a molecular level to determine age.
Researchers discovered the aging process occurred more rapidly in a young dog and then plateaued from mid age until death. Human aging occurs far more gradually from late teens.
It is hoped this and other studies will assist scientists in further studies of aging in dogs and humans, including the treatment and care of elderly canines.