BIOB 272 1st Edition Lecture 34 Outline of Last Lecture MacroevolutionI. Macroevolution vs. MicroevolutionII. Life: the first 3 billion years- Pre-Cambrian Fauna- Cambrian Fauna- Cambrian Explosiono What triggered the Cambrian Explosion Morphological Innovations Ecological Opportunities- RodiniaIII. Calculating Rates of Origination/Extinction from Fossils- Adaptive Radiationi. Ecological Opportunityii. Morphological InnovationIV. Causes of Decline in Diversity- Extinctioni. Background Extinctionii. Mass ExtinctionThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- The Five Mass ExtinctionsV. K-T Extinction- Causes- Evidence- Other Disasters the Asteroid CausedVI. Mass Extinctions Random?VII. Earth’s Sixth Mass Extinction - Humans- Habitat Loss- Increasing CO2 Acidifies the OceanOutline of Current Lecture Human Evolution and DiseaseI. Host-Pathogen CoevolutionII. Tracing the Origin and Spread of Diseasea. Influenza- Flu Life Cycle: - How are Viruses Selected to Make Flu Vaccines?- Predictions for Vaccines are Based On- Influenza Pandemics- Virus Hemagglutinin Genes- 2009 Flu EpidemicIII. Antibiotic ResistanceCurrent LectureHuman Evolution and DiseaseIV. Host-Pathogen Coevolution- Inherent conflict between a host immune system and pathogen- Strong natural selection for pathogens to escape host defenses- Results in rapid evolution of both host and pathogens- Paper: Localizing Recent Adaptive Evolution in the Human Genomeo Identifying locations on the genome that have experiences selective sweeps is an important step towards understanding the molecular basis of adaptive evolutiono Scanned for positively selected genes in the genomes of humans and chimpsV. Tracing the Origin and Spread of Diseasea. Influenza- Flu Life Cycle: viral genome= 8 RNAs, 10 geneso Flu Virus contains: Hemagglutinin, neuraminidase, proton channel, RNA, matrix proteino Two major surface proteins: 1. Hemagglutinin= target and entry by binding sialic acid on host cell surface Has antigenic sites= primary site of host immune system- part of flu vaccine=primes immune system Evolves VERY rapidly2. Neuraminidase released- the basis of subtype designations (i.e. H1N1)- How are Viruses Selected to Make Flu Vaccines?o Flu viruses selected for inclusion in the seasonal flue vaccines are updatedeach year based on which flu virus strains are circulating and how they are spreadingo 141 national flu centers in 111 countries- conduct yearly surveillance and studies flu trendso Base seasonal flu vaccines based on surveillance-based forecasts about what viruses are most likey to cause illness in the coming season- Predictions for Vaccines are Based Ono Serial extinction of lineageso Current virus descend for single early lineageo Surviving lineage tends to show elevated evolution in H antigenic siteso Usually the one with the most amino acid divergence in Hemagglutinino Sometimes predictions are wrong- or there is additional evolution- Influenza Pandemicso 1918-1919: Spanish Flu (H1N1) 10-40% of the worldwide population became ill Over 50 million people died 675,000 deaths in USo 1957-1958: Asian Flu (H2N2) 1-2 million deaths, about 70,000 USo 1968-1969: Hong Kong Flu (H3N2) 1 million Deathso 2009-2010: Swine Flu (H1N1) About 18,000 Deaths Pandemics usually result form flu reassortment= mixing of the 10 geneso Co-infection within host cello Cross-species infection- Virus Hemagglutinin Geneso Strains depend on protein types and the ability of host antibodies to recognize them H3N2= Hemaglutinin-3, neuraminidase-2 1968 global H3N2 pandemic caused by acquisition of H3 from non-human source= bird flu strain- 2009 Flu Epidemico Resulted from multiple reassortment eventsVI. Antibiotic Resistance- Antibiotics: chemicals that kill bacteria by disrupting biochemical processeso Exert strong natural selection for resistant bacteriao Important and very effective tool in improving human health- their continued effectiveness is crucialo Not useful against the common cold/flu- Antibiotic Resistance: evolves rapidly and several common human infections are in danger or rapidly evolving super-resistant strains- Over/inappropriate Use of Antibiotics: leading cause of this due to rapid resistance and arguably among the major health concerns of our time- Antibacterial Soaps promote the evolution of antibiotic resistance and should be used only when medically necessary- Treatment of agricultural feed with broad-scale antibiotics improves weight gain, etc of animals but is harmful for human health because indiscriminant use of antibiotics in the environment actively selects for resistant strains of