Sediment Below the Evaporite

We are Alexa Boesel, Oliver Goodman, and Fred Cohan from Wesleyan University, and here is our next story for Invisible Life! These are exhilarating days for the discovery of bacterial diversity, much like an earlier golden age of biological discovery two centuries ago. In the early 1800’s, European naturalists traveled the globe in search of … Read more

Speedy Speciation in Bacteria

Microbiologists have identified over a hundred phyla of bacteria, groups that are astonishingly disparate in their cell architecture, physiology, biochemistry, and most importantly, their ecology. Our lab has been interested for decades in the first step toward this ecological diversification. This is speciation, where one lineage splits into two “ecotypes” that can coexist indefinitely as … Read more

What are species?

Several years ago I was commissioned by Elsevier to revise Ernst Mayr’s entry on “Species” in their Encyclopedia of Genetics.  I was honored to be revising Mayr’s chapter, as he profoundly influenced me (and many thousands of others) on the nature of species. Because I have come to disagree with Mayr on many issues of … Read more

Rapid Ecological Diversification in Bacillus

In our last posting, we addressed the controversy over the speed of ecological diversification in bacteria. Some say that ecological diversification is almost a daily process, that every bacterium out there is unique in its ecology; others say diversification is extremely slow, so that we can discover whole swaths of closely related organisms that are ecologically interchangeable. In … Read more

Are There Species in the Bacterial World?

It is our pleasure to inaugurate the Cohan Lab’s Facebook, Twitter, and WordPress sites on microbial ecology! Our goal is to discuss and raise interest in new research in microbial ecology, including our own. Our lab in Wesleyan University’s Biology Department focuses on the origins of bacterial diversity, particularly the origins of bacterial species. Our … Read more