map (function, iterable, ...) Â¶ Apply function to every item of iterable and return a list of the results. If additional iterable arguments are passed, function must take that many arguments and is applied to the items from all iterables in parallel.
The grey hair ârule of thumbâ is that by the age of 50, half of the population have lost the colour in 50% of their hair. When researchers tested this rule, they found that 74% of people aged between 45 and 65 had grey hair, with an average intensity of 27%.Generally, men have more grey hair than women.he grey hair ârule of thumbâ is that by the age of 50, half of the population have lost the colour in 50% of their hair. When researchers tested this rule, they found that 74% of people aged between 45 and 65 had grey hair, with an average intensity of 27%. Generally, men have more grey hair than women.
Legend has it that Marie Antoinette's hair turned white the night before she was guillotined. Presumably the stress of impending decapitation caused her locks to lose color within hours. Extremely unlikely, scientists say, but stress may play a role in a more gradual graying process. The first silvery strands usually pop up around age 30 for men and age 35 for women, but graying can begin as early as high school for some and as late as the 50s for others.