What do these "<<<<<<<" mean?

(from pkgsrc/www/mozilla)
BUILD_DEPENDS+= autoconf:../../devel/autoconf
<<<<<<< Makefile
BUILD_DEPENDS+= zip:../../archivers/zip
=======
BUILD_DEPENDS+= zip:../../archivers/zip
>>>>>>> 1.41
DEPENDS+=       gtk+>=1.2.8:../../x11/gtk

This causes:

rainier:/usr/pkgsrc/www/mozilla$ make
"Makefile", line 15: Need an operator
"Makefile", line 17: Need an operator
"Makefile", line 19: Need an operator
Fatal errors encountered -- cannot continue

I also found it in Packages.txt:

<<<<<<< Packages.txt
   browser such as navigator (pkgsrc/www/navigator) or lynx (pkgsrc/www/lynx).
** a few lines here **
=======
** a few more lines here **
   subdirectories will be searched for all the binary packages.
>>>>>>> 1.115

Thanks,

   Jeremy C. Reed
   http://www.reedmedia.net/