Since 2020, the world has been stuck in stand still of course due tot he rise of COVID-19. As a result we have all been stuck at home, avoiding as many strangers as we can. This pandemic has increased the amount of interest the average person has in viruses. As a biology student, many of my friends and family love to ask me questions about biological topics, many of which I can answer well but I’m still a student and sometimes I don’t have the best answer to give. One of these questions I have gotten at least a couple times is whether or not viruses are alive. While I freely talk about how viruses evolve and adapt, I have to think twice about whether or not viruses are alive. My gut answer would be to say “No, viruses aren’t a live of course” based on the fact that viruses are never mentioned in my biology courses about evolution and genetics, however I always have this feeling in the back of my mind that this may not be the case, or at least, it is not that simple. I want to take this blog post as an opportunity to address this question, however the answer isn’t that simple, but I’ll try to lay it out as simple as a I can.
Let me first go into viruses evolving. Viruses evolve in similar ways to the way living organisms do. Viruses have genomes consisting of DNA and RNA. The DNA and RNA are the basis for evolution in living organisms, and as a result, viruses as well. DNA and RNA are subject to changes to their nucleotide bases, and genetic recombination. Viruses replicate at a very fast rate, so their evolution cycle is incredibly fast compared to most, which is why we are continuing to get new variants of COVID-19 so quickly, just about every time we start to feel a bit comfortable again. However if viruses evolve like living things, why are they not always classified as living?
In general, cells are considered the most basic forms of life. Living organisms can be unicellular or multicellular, but regardless they rely on cells for the basis of their life. All bodily functions are driven by cells, organs are built up from tissues of cells, and DNA and RNA are found and replicated within the cells. Viruses contain genetic material, however they do not have cells. The genetic material of viruses stay within a protein coating, however that is it, they have no cells, however they do rely on infecting cells to survive. Viruses infect cells, and replicate themselves to spread. When the cell the viruses infect divides, so to do the viruses, and so they spread even further.
So are viruses alive? Well they evolve like living organisms and carry genetic material like living organisms, but lack cells that would more easily classify them as living. So what are they? Really this question can only be answered if we were to have a definitive answer on what is life. If we decide that for something to live, they need cells, than simply put, viruses are not alive, simple as that. However the fact that the question always pops up makes viruses a very interesting case in the world, as they are generally thought of as not living, but show a case of an entity that acts like that of a living organism, but is not one. I’m no scientist so it isn’t my place to give a definitive answer, but if I were to pick a side, I side with most scientists and say “No Cells? No Life”. That being said, this makes viruses almost even more interesting than that of living organisms, because what exactly are they? I suppose they could simply be replicators and nothing more. Does it really matter if viruses are alive though? Simply put, viruses exist and will continue to terrorize the lives of those who are alive.
- Koonin, & Starokadomskyy, P. (2016). Are viruses alive? The replicator paradigm sheds decisive light on an old but misguided question. Studies in History and Philosophy of Science. Part C, Studies in History and Philosophy of Biological and Biomedical Sciences, 59, 125–134. https://doi.org/10.1016/j.shpsc.2016.02.016
- Pearson. (2008). “Virophage” suggests viruses are alive. Nature (London), 454(7205), 677–677. https://doi.org/10.1038/454677a
Applied Plant Ecology Winter 2020 