A glimpse of microevolution in nature
Some canyons in Israel have north and south-facing slopes that have completely different environments, despite their close proximity. In this article in Microbiology Today (pdf) Johannes Sikorski looks at the micro-organisms that live in these habitats and come to some surprising conclusions that might help us understand micro-evolution rather better:
Bacteria and archaea are genetically, phylogenetically and physiologically very diverse. But how does such diversity start to evolve? How do the first subtle and tender lineages begin to accrue? Oh, you might say, that’s trivial. Have a look at the textbooks and you will find everything there about the evolutionary interplay of mutation, recombination, natural selection and genetic drift. The theoretical framework of population genetics is extremely well-developed. Even more, you insist, microbial microevolution has and still is being analysed in very elegant laboratory experiments, where microbes are allowed to mutate, adapt and evolve in test tubes under very stringent and therefore reproducible and adjustable conditions. But may I remind you that the majority of bacteria are neither evolving in a computer, nor are they living in the pencils of mathe-maticians and theoretical population geneticists, nor in laboratory test tubes, although all these approaches yield tremendous results. Most bacteria live outside in the environment, in water, soil, rocks, plants, etc. Here, where they face a great plethora of biotic and abiotic challenges, they evolve and speciate. Shouldn’t we look at how evolution happens in nature, even though as passive observers, we researchers cannot control this process? What are the decisive factors? Is it possible to catch a glimpse of such a natural evolutionary experiment?
Related:
- What is a bacterial species?
- Genomic islands in bacterial evolution
- Evolution of root nodule symbiosis with nitrogen-fixing bacteria
Tags: Bacteria, Biology, Environment, evolution, Microbiology, Science
