Meet Michiel Dijkstra, from the Frontiers Press Office. Before coming to us, he did a PhD on social evolution at the University of Copenhagen, and worked as a postdoc at McGill University and the University of Lausanne.

*Entirely* coincidentally, he picked as his personal favorite a paper from Frontiers in Ecology and Evolution.

Read the paper: http://fron.tiers.in/go/8R17QF

Otero-Bravo A and Sabree ZL (2015) Inside or out? Possible genomic consequences of extracellular transmission of crypt-dwelling stinkbug mutualists. Front. Ecol. Evol. 3:64. doi: 10.3389/fevo.2015.00064

Michiel writes: “This paper is on a fascinating symbiosis: between stinkbugs (insects in the superfamily Pentatomoidea) and the bacteria that live inside their guts. The stinkbugs can survive without these bacteria, but develop more slowly and die faster without them.

Here, Alejandro Otero-Bravo and Zakee L. Sabree from The Ohio State University review the evolutionary effects of the symbiosis on the genome – that is, the ensemble of the DNA, including genes – of the bacteria. The genome has shrunk and partly degenerated. But interestingly, not to the same extent as in many other bacteria that live in association with insects.

The researchers explain this from the way the female stinkbugs pass the bacteria on to their offspring: by smearing them on the surface of the eggs. Until the bacteria are swallowed by the stinkbug hatchlings, they remain exposed to UV light and desiccation, while they must also survive the passage through the guts of their host. Simply put, the bacteria couldn’t survive without certain genes – which bacteria that always live inside the cells of their hosts could afford to lose.”