Yesterday's Kin

This should have been a novel (and hopefully the author will turn it into one)

Reviewer's Aside: Auuggghhh! So frustrating!

Yesterday's Kin starts out with aliens arriving at Earth, parking their spaceship, and then just hanging out for a few months without saying anything, despite all efforts humans make to communicate with them.

Suddenly, one day, they finally speak. And what they have to say is both marvellous and horrifying: firstly, that they and we share common ancestors and thus common genetic traits, and secondly, that there is a world-killing cataclysm heading our way.

In this "Separated at Birth" tale, a human geneticist who has made a groundbreaking discovery in mitochondrial DNA research is singled-out by the aliens to be part of a joint research team. But while other members of the team are engaging in research to help stop the apocalypse, the geneticist is assigned to a very different project: to identify those humans who are distantly related to the aliens...

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