why is variation important?
Variations are very important for organisms to survive because if there were no variations among living organisms there would have been no evolution or change and natural conditions do not remain constant they keep on changing. If variations stops then we would not be able to adapt to the changing conditions and can prove catastrophic to us. You can refer to the case of beetles in the study material
1.)When the immediate environment changes and stress is put on organisms. Then those who have the variation that will become beneficial in this environment will be reproductively more successful.
2.)its important because if we were all the same, we would have the same immune system and everything else. so where as some people can fight colds and diseases such as lung cancer, if we were all the same then we all may or may not fight off diseases. so in short, if a deadly disease struck and we were all the same, we could all be immune to it, or it could wipe out the entire human race. and a bunch of other stuff...
HOPE THAT HELPS:-)