The issue focused on the role of [genes](https://www.reddit.com/r/explainlikeimfive/comments/3amh84/eli5_why_do_animals_have_more_white_hair_than_black/) in white hair color as well as the effect of different skin colour on the distribution of white hair in an animal: 
 
 &gt;They found that in all three species of echidnas with white hair, the distribution of white hair was almost completely