Sars-CoV-2 has been bullying us for about two years now, so it makes sense that my blog posts have so far been very COVID-centric. As a result I’ve been looking to study viruses and how they work quite a bit.
Specifically here I will be comparing viruses to that of invasive species, and how their spread and effect follow very similar models. Invasive species are of course species that “invade” other ecosystems they are not native to. Typically invasive species will cause harm to other species in an ecosystem in many ways. Some of these effects include increased fire vulnerability, predation/competition of native species, loss of biodiversity, spread of diseases, and much more.
Invasive plant species can be particularly threatening because these species tend to have massive effects on their new ecosystems due to how they can often compete with and take away resources from other plants, and plants tend to be the primary species in the ecosystem, effecting all other species in the ecosystem. Invasive plants also tend to spread and grow very quickly, which allows them take over new ecosystems and continue to spread into others. Typically invasive plant species have ways to spread their seeds fast and far. An example is the Canada Thistle, which is native to the Mediterranean, which is now spread worldwide, notably in Canada as the name implies. The Canada Thistle uses it’s large roots as a method of spreading over larger areas for seed germination, and the seeds can last in soils for up to 22 years. The fact that the seeds can lay dormant for so long is a huge cause of invasive species as the soils that they can lay dormant in can move and relocate, causing the seeds to grow in locations, making them invasive tot he new region, and nobody even realized the seeds were there.
So what does this all have to do with viruses and Sars-CoV-2? In a previous blog I even went into detail about whether viruses are alive or not. Regardless of their living status, viruses know how to spread far and spread quick. There is a reason we use the term “viral” whenever something starts to trend quickly over the internet, and that is because the word has its origins meaning related to viruses. Typically viruses remain dormant until a change in their genetic makeup allows for faster spread. Once the change is made and is picked up by a carrier, if the virus is effective, it can easily start infecting more hosts, and the more hosts it infects, the faster it begins to spread. This is not at all dissimilar to the model for invasive plant species, which thrive off of quick growth and spread, often causing harm wherever they go. The comparison isn’t perfect, because it is hard to say if a virus is invasive, but the similarities are there.
Sars-CoV-2, the virus causing COVID-19, of course dates back to late 2019 to early 2020 in China. The speed at which this virus is able to spread allowed for hosts to carry the virus into new locations, and immediately start finding new host after new host. Like invasive species they grow and spread very quickly, and the further they spread, the faster and faster they can replicate. The dormant seeds of some species such as the Canada Thistle is comparable to that of asymptomatic carriers of Sars-CoV-2, who are unaware of their status of having the virus, making them especially effective and spreading the virus to many new hosts. At this point we are all familiar with this, as we often find that people meetup with others who don’t believe they have the virus as they show no symptoms taking tests days later and realizing they now have the virus. Sars-CoV-2 may not be an invasive species, but it is most certainly invasive to our lives.
Applied Plant Ecology Winter 2020 