It took me a while to process what I read in Darwin’s Surprise, mainly because I was in awe every couple sentences. I remember reading a particular phrase that really blew my mind; “using widely available information and DNA they bought through the mail”. This might have just been me, but I was really surprised that people could buy DNA through the mail. How would you be able to package DNA? DNA is very small, and I just can’t see it arriving inside of anything large in the mail or anything, only a small envelope, no bigger than a dime, similar to what you may see on cartoons. On another note, I was also surprised to find out that mammals might not have ever been able to develop a placenta had it not been for viruses. I had never given much thought as to how placentas came to be, I sort of just thought that it was always there. Obviously, I wasn’t using my AP Bio knowledge. After reading how the syncytin used the same mechanism that retroviruses use to attach to the host cell, how biologists in the 70s saw a layer of retroviruses on syncytium in baboon placentas, and how the syncytium was the primary barrier between mother and fetus, I sort of got the impression of how mitochondria can be found in cells. It made me think that at some point in time, there was a symbiotic relationship (mutualism) between a retrovirus and the placenta (which resulted in engulfment, similar to what the endosymbiotoc theory proposes), which does not make sense, because viruses are essentially parasites. This might explain why I was so surprised about the connection between the placenta and retroviruses, but that might be a reach (I don’t think my brain could have thought about all that before actually thinking it through for a couple minute).
Overall, I was surprised that viruses could possibly benefit people. So far in my life, I’ve only heard about how viruses were bad, so it was nice to hear about viruses from a different perspective. It’s strange to think that they have played a role in mammals developing a placenta or that they have been in our genome for so long. Viruses have definitely been more beneficial to our survival that I had previously imagined.