How does evolution explain drastically different appearances between males and females. I’m havening trouble wrapping my head around this. If our off-springs get a 50/50 split of DNA from the male and the female, then how is it that a bird like the Mandarin duck look so different between the sexes?

I would think that if something is getting a 50/50 split then it should have traits from both the mommy and daddy, and thus should resemble both to some degree. I’m sure I’m missing something stupid, but I’m still trying learn and understand how the theory of evolution can produce things like this.

Thanks for any help!