A couple books that I'd recommend for their attention to biology and genetics as the scientific driver: Julie Czerneda's Species Imperative Trilogy: Survival, Migration, and Regeneration. Maragaret Atwood, anything, but recently the MaddAddam trilogy: Oryx and Crake, Year of the Flood, and Maddaddam. Nancy Kress' Sleepless series: Beggars in Spain, Beggars and Choosers, and Beggars Ride.
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