Structure of pubring.gpg

[Oskar L.]

Why are the keys in pubring.gpg in the order in witch they were imported?
Is this not considered a security risk? Would it not be safer and more
convenient to have the keys sorted by user ID or key ID?

I deleted all files in my .gnupg directory, and then imported a public
key. Then I exported the key in binary form and compared the file with
pubring.gpg in a hex editor. The beginning of both files were identical,
but from the middle and onward they differed. How and why are keys changed
when imported?

Oskar