Dominant Species is an unpublished novel by Alastair Reynolds and a sequel to the also-unpublished Union World; according to http://alastairreynolds.com/about/formative-years it was his second novel after Union World, and he has no plans to publish it.
[Dominant Species was] a much better book [than Union World] – in my opinion – and this time my influences were Pohl, Benford and Joe Haldeman. I even went to the extent of making my own “faked” documents to include in the book, in the style of Haldeman’s Mindbridge.
I was dissatisfied with many of the underlying assumptions of the universe and decided my next book would be proper serious hard SF with no faster-than-light, tractor beams etc. There would be no cosy aliens with similar technologies to our own.