Today when I checked my $PATH variable in Z shell (on OS X 10.8.3), I got the following result (I broke the lines for clarity):
/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:
/opt/X11/bin:/usr/local/git/bin:
/usr/texbin:/usr/gcc-4.8.0/bin:/opt/local/bin:/opt/local/sbin
The first and last lines are quite normal. /usr/bin etc. are somewhat default; and /usr/gcc-4.8.0/bin:/opt/local/bin:/opt/local/sbin are what I manually loaded through ~/.zshrc.
However, the middle line is peculiar. X11 and git cannot be default, and they do not appear in .zshrc either. So I suppose there are files other than .zshrc that get loaded at login (I use login shells). What are these files then? Thanks in advance.