I've been a fan of Sheri S. Tepper's ever since I ran across her excellent /Sideshow/ in high school. I've admired her ability to seamlessly construct her books, artfully balancing exposition, wonderful prose, world building, characterization, and plot to make a point without being preachy. All this explains why I had high hopes when I began /The Family Tree./
Unfortunately, my hopes and expectations were quickly let down. /The Family Tree/ is a pageturner, but of the worst kind - I found the sections set in the far future so annoying and cloyingly cute that I read on as quickly as possible, desperate to find out about the weird goings-on in the present day. The sections set in the present are engaging, but curiously flat. Where did Tepper's enormous skill at characterization go? Dora and Abby are likable characters, but not very rounded. They're too pleasant and nice to be truly interesting in their own right.
I read this book right after rereading Tepper's /Grass/ (a Hugo finalist for Best Novel) and the contrast was striking. /Grass/ was filled with fascinated, flawed characters that had real moral dilemmas and issues to work out. /The Family Tree/ is populated with likable but dull archetypical characters. /Grass/ has wonderfully evocative prose that brings its worlds alive. /The Family Tree/, in an effort to keep the identity of the citizens of the far future secret, is rather skimpy on descriptive prose, and the whole is suffused with a sort of not-very-good-young-adults book feeling. /Grass/ had a multitude of themes, including independence/interdependence, the impact of custom, and the relationship between God and humanity - complex themes, stated subtly. /The Family Tree/'s message - we're ruining the Earth by overpopulation and waste, and animals have a right to an unspoiled planet as well - has already been done (very well in Tepper's /Beauty/) and is so baldly stated that it makes me cringe. Instead of leading us through ideas like /Grass/ did, /The Family Tree/ hits us over the head with preachiness.
I would be more disposed to look on this book kindly if it were a debut. The plot is ingenious and often surprising, and it manages to link together many fascinating ideas. Unfortunately, the plot also feels gimmicky - I felt distinctly tricked when the identity of the far future people was revealed.
In sum, /The Family Tree/ is a somewhat entertaining read, but we deserve more from one of SF's finest novelists. Do yourself a favor and hunt down a copy of /Grass/ or /Beauty/ instead.