There are few things more irritating than a negative criticism, phrased as a question, but posed by an anonymous reader.
On Andromeda, the flora and fauna are, indeed, apparently compatible with Earth species (the relevant qualifier being 'apparently'.)
The human immigrants and the long-gone aboriginals have been dependent on replicated food, using the very limited range of edibles as a supplement. The long-term aim is to render the population independent, as far as possible, of advanced technology, providing natural, organic foodstuffs. Hence the introduction of a range of Earth vegetables and the deer and bison as an eventual source of animal protein.
I appreciate that there is a point of view that insists on the preservation even of a moribund, impoverished, eco-structure, but I suspect that it is a minority position.
To say more would be to introduce a spoiler, I think.