[@mskamran]

@mskamran asked the Naked Scientists:
   If there has been 24 hrs for daylight and 24 hrs for night, would our bodes have been evolved to work/sleep accordingly?
What do you think?

[Don_1]

That is a distinct possibility. Sleep is an important part of our lives and like other dinurnal animals we sleep during the hours of darkness to protect ourselves from the injury we would sustain through being unable to see our surroundings. I'm pretty sure that if a day on Earth were 48hrs we would have evolved to take advantage of the available light. But it is worth baring in mind that many dinurnal animals take daytime naps and such naps are good for us too.