I thought I'd posted this one earlier but can't find any trace of it so, if it is already here, forgive me for the duplication.
This is a photo of a lifetime. The chances of my coming across another example of this are virtually nil and most people will never see a case in their entire life. Others, however, may see several.
Leucism is a genetic disorder and leads to the total or partial absence of colour in hair or feathers of animals and birds. It does not affect the colour of the eyes as albinism does and has no other effect on the creature other than to often reduce its chances of finding a mate.
This is a partially leucistic sparrow I came across in May of this year.
View attachment 181095