what is with the ears? are they ears?

[GogetaBlue]

look at the pictures do you see the ears? are they ears? most aliens have them its SUPER weird, what do you guys think?

 

[India Actual]

Ears

 

[Beerus]

Yeah, they are all ears.

Hit and Frieza seem to be similar lifeforms from two different universes. Both of which have alien characteristics. Neither race is explored in depth.
Cell has those ears because of his DNA. He has Frieza's DNA so he will naturally have some features of the guy.
Buu is a Majin which is just a demonic ancient alien race.
Burter is a mutant. If you are familiar with Futurama, both aliens and mutants appear similar but are not the same.
Jiren is a typical "Grey". He is based on the grey aliens that are believed to exist in the real world by a lot of people. These guys:

They are similar to reptile ears which are just rounded holes.I would imagine that the expansion of the size that comes outward is to emphasize that they are ears. I believe they are all somewhat based on the Zeta Reticuli which are more human-like than a standard Grey.

 

[GogetaBlue]

 

[LividJay]

I've always wondered the same thing. You'd think they'd get a little more creative with ears.

 

[India Actual]

Goku is technically an alien, his origin planet isn't earth. It is planet vegeta, and he had a monkey tail. Look at his ears, seems pretty normal to me.

Its the hair that gives them away. Freaks.