http://www.graphique3d.republika.pl/

It is one of galleries which convinced me to buy V5I. Maybe SciFi is not your favourite subject but there are excellent examples of ecosystems. By the way, the renderings were used in promotion of Vue.
Currently, import from Poser does not work perfectly and many corrections have to be done in the material editor so as to remove plastic and flat look but I hope that incoming patches will correct it. Nevertheless, it is really impressive software IMHO.
As agiel mentioned, the backroom is a good place for start.

Good luck :)