2. Ginko Biloba
According to evolutionary theory, living things that are better adapted to their environment are more likely to survive and pass on their genes. This process, called natural selection, is often driven by competition—for food, space, or protection against diseases.
One example of this kind of competition is known as the Red Queen effect. It describes how two species—like a host and its parasite—must keep evolving just to stay in the same place. As one gets better at attack, the other must get better at defence. Something like this may be happening between ginkgo trees and microbes. Ginkgo trees might have first developed ways to stop bacteria from forming sticky biofilms on their leaves. This would help the tree get enough sunlight, oxygen, and nutrients. In response, some microbes may have evolved new ways to protect themselves—for example, by changing their cell membranes so the ginkgo’s antimicrobial proteins don’t work as well.
Over many generations, this could lead to an ongoing “arms race” between ginkgo and microbes, with both sides constantly adapting. In the end, they may reach a kind of balance, where both can survive, even though they are still in competition.
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.