3. Chilli (Capsicum spp)
According to evolutionary theory, organisms that are better adapted to their environment are more likely to survive and pass on their genes to the next generation.
Competition for resources, such as food, or resistance to diseases is a selection pressure that drives evolution. When species need to continuously evolve just to keep ahead of their enemies, it’s called the red queen effect.
Something like this might be happening between plants and microbes, though direct cause and effect can’t be traced here. Chillies might have first adapted defences against microbes that harm them by using a different secondary metabolite than capsaicin to attack microbes. Then, the microbes may have adapted the antimicrobial efflux pump described in Staphylococcus aureus.
Once the microbes have these special pumps, the chillies that were better able to survive and pass down their genes were those that also happened to have capsaicin, which disables the drug efflux pumps in the bacteria.
Do you think we should hope to live in a microbe-free world?
You might think that it seems like microbes have done more harm than good. Maybe, in that case, we should just get rid of them altogether!
But don’t forget, microbes play an important part in human, animal, and plant health. In some places, there has been a lot of antimicrobial pollution by humans (where we accidentally release antimicrobials into the environment, often through run-off into rivers from antimicrobial drug production).
Where there’s pollution and changes in the microbes in the environment, the soil and water become less fertile for the growth of plants and animals. What’s more, we need microbes, too! Our gut health is all about having a good balance of bacteria helping us digest our food, protecting our skin, and helping us fight some infections.
We shouldn’t aim for a microbe-free world, but it’s important to control the spread of superbugs.
Please note: for those taking the trail in March/April, chillies will be quite small, so keep a keen eye out!