And why could they not have been created as is? You know, like dodge has a magna and a Neon - similar only in that they were designed by the same company and for the same roads, but for different purposes.
The paint comes from the same supplier too.
No one can prove they weren't. But of course if evolution is not happening, things will die out with every change in climate. And of course, we can observe organisms adapting genetically to changes in environment.