It is a perfect example of a natural selection.
(I'm not sure if this is the exact answer that you are looking for.)
Well are you gonna show us the question
They are different in structure as one serves in an open system (lymphatic system) while the other serves is closed system (circulatory system).
Hope this helps!
*This question is common, so this answer I use a lot. I copied my own work.*
Answer:
colorblidness is carried on the X cromasome. since it is resessive it can be covered up. woman have 2 X cromasomes so both have to have it or she wont be color blind. men only have one X cromasome so its more likely that their just one X can have it
Explanation:
