I wish I knew how this happened. Using Texshop, under Preferences, encoding is UTF-8. File contains the following lines in the preamble:
When I compiled the file, I got all sorts of instances like the following:
When I went to Macros=>Encoding it seems the file is encoded in MacOsRoman. I changed that setting to UTF8 (I don't know if this overrides TexShop's global preferences) but I'm still getting these wild characters.
-How do I get rid of them?
The file otherwise compiles properly.
Edit: I did convert the file to UTF8. I used Textwrangler to "Zap Gremlins" and most of these disappeared. However, I have to go back and add back in some high-ASCII characters that ere deleted, like é.
But wait! Now when compiling I get the following error:
Package inputenc Error: Unicode char \u8:éMa not set up for use with LaTeX.
I used the utf8x package instead of utf8, and added the following to the beginning of the file:
% !TEX encoding = UTF-8 Unicode
which was a suggestion by user27221 in a related question.
I'd still like to know how to get rid of these without resorting to an obscure command (Zep Gremlins) in a specialized program that I may not always have access to.