Alien Clay by Adrian Tchaikovsky

From Arthur C. Clarke Award-winning author Adrian Tchaikovsky comes a far-future epic that confirms his place as a modern master of science fiction, in which a political prisoner must unlock the secrets of a strange and dangerous planet.
The planet of Kiln is where the tyrannical Mandate keeps its prison colony, and for inmates, the journey there is always a one-way trip. One such prisoner is Professor Arton Daghdev, xeno-ecologist and political dissident. Soon after arrival, he discovers that Kiln has a secret. Humanity is not the first intelligent life to set foot there.
In the midst of a ravenous, chaotic ecosystem are the ruins of a civilization, but who were the vanished builders and where did they go? If he can survive both the harsh rule of the camp commandant and the alien horrors of the world around him, then Arton has a chance at making a discovery that might just transform not only Kiln, but distant Earth as well.