Sometimes a picture or, in what follows, a video is worth so many words. Let’s consider the COVID variants; how could there possibly be so many so quickly. The answer, of course, lies in the work of Darwin.
Now we all know that Darwin uncovered the idea of evolution, the survival of the fittest. And while most accept the idea, others point out that there are gaps in the evolutionary record, and there is no link between us and our previous iterations. The other misunderstanding we might have is that many of the examples of evolution involve dinosaurs becoming birds or wooly mammoths becoming elephants – they are old news and took a lot of time.
Survival of the fittest simply means that the species most capable of living in the environment dominants – so a changing environment exerts different pressures to promote some traits over others. In the microbial world, there are many drivers, including susceptible hosts, antimicrobials, and dare I say, vaccines. Evolution does take time, lots of generations for a “mutation” to become a dominant feature. With our lifespan of 70+ years, we don’t see the changes. But the lifespan in the microbial world often differs.
In this case, we are talking about E. Coli, which has a generational time of approximately 20 minutes. In the video, E. Coli are put onto a very large petri dish that has columns with increasing amounts of lethal antibiotics – the center column has enough antibiotics to kill any E. Coli we usually see. I’ll let the Harvard researchers pick up the narrative and see you on the other side of the video.
Ten days! Other studies found some variation on that time frame, but consider how quickly because of E. Coli’s population and generation time it took for a mutation to become the dominant form – you are not ever going to get a better example of survival of the fittest; unless you consider say COVID-19, where those dynamics are playing out in real-time, with real consequences, for you and me and the coronavirus. COVID-19 is not going away; there will be an equipoise between us and a variant “we can live with.” But the rapidity of the dance between us and COVID makes advice quickly out of date; bureaucratic delays and language further muddle the advice. You can take this as a bumbling, fumbling government bureaucracy that should never have been trusted or as a group trying to do its best (although hampered by its size and rules) with an enemy that changes more quickly than they can produce a memo. I choose the later.
A last thought. That little demonstration should indicate how important the discussions of antimicrobial resistance are to our health. Giving antibiotics to our animal food supply to make them bigger and less costly comes with a price payable in healthcare. We need to pay more attention to what we are and are not doing, not just in the US (where we are doing well) but globally – microbes, as demonstrated in the headlines and hospitalizations, get around. There are other drivers of survival of the fittest that are on the event horizon, water and climate change – human generations are not as rapid as those of the bacteria, we may not adapt as quickly as they do.
Source: A Natural History of the Future Rob Dunn This is an excellent book that I highly recommend if you want to understand the biological laws underpinning our future