How did viruses learn to utilize the workings of a cell?

Question

This is my first post here, so excuse me for its simplicity.Viruses can infiltrate a cell, overtake it and multiply. It has projecting fibers whose ends are shaped as kind of a "key" to a mobile sentry on the cells membrane so it can be permitted access into the cell. When it enters the endosome of a cell, a protein pump blows an acidic gas onto the virus to break it down, thinking it's a special nutrient. But the virus expects this of course, and when the protecting fibers break off (and so too the body of the virus) proteins are released that rips apart the skin of the endosome so the virus can escape.These are just two of many things the virus does to compromise a cell. Its entire existence is for the sole purpose for infecting a cell, and it seems to know how to do that perfectly. How did the virus evolve to know how to do things like this?

Answer 1

This is a great question! Thank you, and I have had students ask this question before, so hopefully this explanation helps adjust your thinking toward a more scientifically accurate view of how viruses have evolved.

Viruses don't "know" specifically how to hijack a cell and take it over even though that is their primary goal. Viruses have evolved over time through mechanisms such as natural selection, genetic drift, mutation and gene flow. Through the process of natural selection if the virus is unable to enter the endosome of the cell or if it is destroyed by the cell then it no longer replicates. However, if only one virus enters and that is due to a genetic advantage that the virus has, it is able to replicate and then eventually lyse the cell releasing hundreds of phage progeny into the surrounding environment. The infection spreads rapidly and those viral particles that have acquired the selective advantage in the population are able to reproduce progeny that also possess the selective advantage. This is how organisms evolve over time.

Best of luck to you!