Latest News

Clues beginning to emerge on asymtomatic SARS-CoV-2 infection
Back in November of 2020, during the first wave of the COVID-19 pandemic, I was teaching an in-person microbiology laboratory. One of my students had just been home to see his parents, and they all c…
Read more
Could there maybe be better uses of genetics and probiotics?
Professor Meng Dong and his laboratory have created a probiotic that can metabolize alcohol quickly and maybe prevent some of the adverse effects of alcohol consumption. The scientists cloned a highl…
Read more
ChatGPT is not the end of essays in education
The takeover of AI is upon us! AI can now take all our jobs, is the click-bait premise you hear from the news. While I cannot predict the future, I am dubious that AI will play such a dubious role in…
Read more
Fighting infections with infections
Multi-drug-resistant bacterial infections are becoming more of an issue, with 1.2 million people dying of previously treatable bacterial infections. Scientists are frantically searching for new metho…
Read more
A tale of two colleges
COVID-19 at the University of Wisconsin this fall has been pretty much a non-issue. While we are wearing masks, full in-person teaching is happening on campus. Bars, restaurants, and all other busine…
Read more

News

Gut microbes’ role in species divergence


 

It is well known that gut microbes play an important role in the health of many organisms.  Seth Bordenstein and Robert Brucker, biologists at Vanderbilt University, were curious to see what other effects these microbes may have on an organism.  They studied the role of microbes in three related species of parasitic jewel wasps.  Two of the species, Nasonia giraulti and N. longicornis, are closely related, whereas the third species, N. vitripennis, diverged about 1 million years ago.  Offspring of  a cross between N. giraulti and N. longicornis generally result in surviving offspring.  However, when either specie was breed with N. vitripennis, almost all male larvae in the second generation die. 

With the knowledge that the gut microbes in N. vitripennis differed from N. giraulti and N. longicornis, Bordenstein and Brucker wanted to know if the different microbes played a factor in unsuccessful crossing of different species.   To test this, scientists raised all three species of Nasonia without gut microbes by only feeding them sterile food.  Interestingly, when the the gut microbe free N. vitripennis was breed with the N. giraulti wasps, almost all of the second-generation wasps survived.  The surviving wasps where then reintroduced to bacteria and most of them died.   

This experiment provides evidence that parental genes not meshing correctly in hybrids is not the only thing that separates species.  It provides an entire new way to understand evolution, looking at the compatibility of parental DNA with the offspring’s microorganisms.  For example, some parental genes might allow the immune system to keep certain gut bacteria in check, and without them the gut microbes might make the animal sick.  This study provides a new and interesting way to look at the divergence of species.