Main Question or Discussion Point
i was wondering if anybody had any thoughts about the symbiotic relationship between us and viruses, and whether the fact that we are vehicles for them motivate them to to change us and modify our evolution.
I don't know that I'd call it symbiotic, viruses use us as replicators, not much benefit from our standpoint.i was wondering if anybody had any thoughts about the symbiotic relationship between us and viruses, and whether the fact that we are vehicles for them motivate them to to change us and modify our evolution.
That's certainly true and I'd agree with all of it. My point wasn't that there isn't some specialized circumstances where we could consider viruses beneficial, my point was in general the relationships between viruses and humans is rather one sided.It is possible that we do derive some benefit from retroviruses, however. We know that retroviruses, either the infectious kinds of the kinds that have become endogenous mobile genetic elements, have the ability to reshuffle our genetic material. For example, a retrovirus can accidentally replace part of its sequence with DNA from the host. When this virus integrates into a new position in the genome, that host sequence will have moved to a new position in the genome where it can possibly adopt a new function.
While this process certainly can be harmful--for example, the idea of oncogenes, cancer causing genes, were first discovered when researchers realized that cancer-causing genes from a variety of tumor viruses were actually genes taken from the host's genome--it is possible that this process has also aided the host's evolution by generating more genetic diversity. For example, this process would promote recombination between different regions of the genome, allowing genes with new functions to arise. This could be one explanation for why endogenous retroviruses are so prevalent in our genomes.
This is a subject I find quite interesting. It is amazing how dependant relationships have evolved to become so species specific in some cases that the loss of one means the extinction of the other.I'm reading Carl Zimmerman's "parasite rex". Aside from being quite readable and extremely interesting, it seems to give examples of how the role of parasites (if not viruses specifically) has been overlooked (in evolution, etc). (E.g., in particular environments >95% of fish the birds catch have parasites, which alter the fish behaviour to better facilitate transmission, and bringing into question the role the birds might play in that ecosystem otherwise.)