The programs in poptree-unix.tar.Z are for (1) constuctiong a neighbor-joining tree or a UPGMA tree from allele frequency data of microsatellite DNA loci or other genetic markers and (2) computing heterozygosities and Gst. The poptree was formerly called njbafd. The name was changed because the program is intended to make population trees. (1) Ftp poptree-unix.tar.Z and poptree-unix.readme onto your system in the binary mode. (2) Type "uncompress poptree-unix.tar.Z". (3) Type "tar xvf poptree-unix.tar". (4) Type "source compile.sh" or "source compile.gcc.sh" to compile the programs. Executables included in the poptree-unix.tar.Z are for the linux (4) Read the read.me file first. If you have problems or comments, please send email to: ntakezak@lab.nig.ac.jp March 16, 2004 Naoko Takezaki National Institute of Genetics Yata 1111 Mishima, Shizuoka 411-8540 Japan