Virology Lectures 2021 #21 - Evolution

Viral evolution, the change of a viral population in the face of selection pressures, occurs faster than in other organisms because viruses produce so many progeny harboring many genome mutations. In this lecture we consider the four main drivers of viral evolution: large numbers of progeny, mutation, selection, and quasispecies effects. We discuss selection by the immune system and how it gives rise to antigenic drift and antigenic shift in the context of influenza viruses and SARS-CoV-2. We conclude by a review of the origins of viruses in the pre-cellular world and why all viruses emerge not de novo, but from existing viruses. Access lecture slides and readings at https://virology.ws/course Become a patron of MicrobeTV at microbe.tv/contribute ——————————— CONNECT ——————————— 🎯 Subscribe to this channel! https://bit.ly/2HOYdNP Instagram: @profvrr and @microbe.tv Twitter: @profvrr Facebook:   / thisweekinvirology   Our Podcasts: https://microbe.tv Contribute: https://www.microbe.tv/contribute/ ——————————— MORE VIROLOGY ——————————— •My Virology Course https://virology.ws/course •Virology Blog: https://www.virology.ws •This Week in Virology https://bit.ly/30uUhrX •Virus Watch https://bit.ly/3ngvQIM •Principles of Virology textbook https://amzn.to/34onDtg ——————————— OUR OTHER PODCASTS ——————————— •This Week in Parasitism https://bit.ly/3ndUNUZ •This Week in Microbiology https://bit.ly/33tOUeO •Urban Agriculture http://microbe.tv/urbanag •This Week in Evolution https://bit.ly/3ne1bf5 •Immune https://bit.ly/2HOyCVb •This Week in Neuroscience https://bit.ly/2So12Yd – Who Am I? – I’m Vincent Racaniello, Earth’s Virology Professor. I’m also a professor of virology at Columbia University in New York. I’ve been doing research on viruses since 1976, and teaching virology in classrooms and online since 1999. On this YouTube channel I share videos of my lectures, podcasts, and more. New videos are uploaded multiple days a week. I don’t monetize my videos because it’s disruptive to learning. If you would like to support our work, go over to https://www.microbe.tv/contribute/ ——————————————————————— #virology #viruses #coronavirus #pandemic ———————————————————————