The aphid room partecipates with a post on aphid cytogenetics since some aphid clones show highly variable karyotypes not only comparing different aphids, but also comparing different cells in the same embryos… so that there is a sort of stability in the instability in the karyotype.
In the Carnival, there are some very intriguing posts and my favourite is On Transposable Elements and Regulatory Evolution at biobabel, where Habib Maroon discusses the exaptation of transposons as regulatory elements ensuring that some genes are transcribed at the right time and place. You have to read it since transposons had some effects in the evolution of pregnancy… how? when? For a reply, simply read biobabel.