what is the hardest question in science that you’ve ever been asked appart from this one haha lol :)

Question: what is the hardest question in science that you've ever been asked appart from this one haha lol :)
- Keywords:
  Question,
  science
Asked by oli to Tristan, Sophie, Ravinder, Matt, Barbara on 9 Mar 2015.
- Sophie Robinson answered on 9 Mar 2015:
  
  This probably is the hardest! I have been asked before why we have five fingers and toes. This is a difficult one as we could do just fine with 4 or even 7 of each!
- Ravinder Kanda answered on 9 Mar 2015:
  
  This is not really a hard question… try harder!
- Matthew Moore answered on 13 Mar 2015:
  
  That’s a good question and I’m not sure really! There are plenty of difficult questions in science which I ask myself and still can’t quite work out, such as species concepts in bacteria and the origins of new bacterial species.
  
  Ultimately all living organisms live on a big genetic continuum, organisms (all of them) have evolved from a common ancestor, diverging over time. Drastic differences are seen in organisms because many in-between stages (ancestral forms), other branches, have died out.
  
  This becomes even more complicated in bacteria as they can trade DNA between each other, evolution doesn’t always occur by distinct branching. I’d love to be able to answer that question of what is a bacterial species.
  
  On the other hand, the analysis of genes is becoming so advanced now and bacterial species are so variable (even within their species) that perhaps the concept of species will become redundant anyway!