Why are some corys bigger than others in the group?

[16gallontanker]

I have 4 peppered corys and one Is much bigger than the other ones.and it's the same with my pair of albino corys why is this ?

 

[Connershawzz]

in my experience with Cory’s , females are always bigger then the males like most fish. Also hard to really know without pictures if anything is wrong

 

[CassCats]

Gender, genetics, and growth conditions play large roles in corydoras size variations.

 

[16gallontanker]

Ok