<font face="Times New Roman, serif" style="color:rgb(0,0,0);font-size:medium;">A recent study, conducted by Professor Seth Bordenstein of Vanderbilt University, proposed that two species of jewel wasp, <font face="Times New Roman, serif" style="color:rgb(0,0,0);font-size:medium;">Nasonia giraulti</font><font face="Times New Roman, serif" style="color:rgb(0,0,0);font-size:medium;"> and </font><font face="Times New Roman, serif" style="color:rgb(0,0,0);font-size:medium;">Nasonia Vitripennis</font><font face="Times New Roman, serif" style="color:rgb(0,0,0);font-size:medium;">, remain separate species largely because of microbe interference, not lethal incompatibility in DNA, as many biologists believed.</font></font>

The study was conducted by raising hybrid larvae and purebred larvae in a germ-free environment, using antibiotics to kill off gut microbes. Cross breeding of the two species in nature typically results in the hybrid larvae dieing off, however in the laboratory setting, germ-free hybrid larvae were able to survive just as well as their purebred counterparts. In further studies, the germ-free hybrid larvae were exposed to two types of guts microbes from regular hybrid larvae, resulting in the demise of hybrids. The two experiments together provided solid evidence of microbes playing a role in maintaining species.

<font color="#000000"><font face="Helvetica, sans-serif"><font size="3"><font face="Times New Roman, serif">How the wasp genome and microbes interact to kill the hybrids is still under study. Bordenstein observed darker pigmentation in dying hybrid larvae as is if secreting melanin, an indication of inflammation. Because the most rapidly evolving part in animals are their immune systems, the darker pigmentation could be linked to the lack of immune responses to gut microbes. This opens the possibility that genes differences between species and their ability to attracts or repels certain microbes may influence species designations. </font></font></font></font>

<font color="#000000"><font face="Helvetica, sans-serif"><font size="3"><font face="Times New Roman, serif">The presentation, reported at Evolution 2013 Conference, surprised many taxonomists as it expanded phylogenetics, the study of evolutionary relationships in organisms, to exploring possibilities of hologenome theory of evolution, a controversial topic dealing with natural selection and the interaction of microbial communities for speciation. </font></font></font></font>