The Population-Genetic Environment - Lecture 1

Overview

Explore the fundamental concepts of population genetics and evolutionary biology in this comprehensive lecture from the Fifth Bangalore School on Population Genetics and Evolution. Delve into topics such as random genetic drift, effective population size, mutation rates, and recombination rates. Examine key experiments and studies that have shaped our understanding of evolutionary processes. Learn about the drift-barrier hypothesis and its implications for genome stability and mutation accumulation across different organisms. Gain insights into the mathematical theories and models used to predict and test evolutionary changes in populations. Discover how population genetics provides a crucial framework for integrating various biological disciplines and understanding the mechanisms driving evolution.

Syllabus

Start
Introduction
Preface
Mathematical Theory and Scientific Understanding
Population Genetics and Evolutionary Hypotheses
Random Genetic Drift at a Neutral Locus is Inversely Proportional to the Effective Population Size
Buri's Big Drift Experiment
Most Demographic Deviations From the Standard Model Cause Ne to be the Census Number
Genetic Hitch-hiking Via Selective Sweeps Depresses Ne Below the Actual Census Size
Allele-Frequency Trajectories for Mutations in Replicate Experimental Yeast Populations
Selection Against the Constant Background Rain of Deleterious Mutations Further Depresses N.
The Concept of Effective Neutrality
Probability of Fixation of a New Mutation
Negative Scaling of N with Organism Size Defines the Range of Mutations Discernible by Selection
The Drift-Barrier Hypothesis
Drift Barriers in Biology
Evolution of Mutation Rates
Quasi-Equilibrium Mutation Rates Resulting From Deleterious-Mutation Load
Analysis of Genome Stability with a Mutation-accumulation Experiment
Mutation in Small vs. Large Genomes
Mutation-accumulation Studies Across the Tree of Life
Drake's 1991 Law for Mutation-Rate Evolution Revisited
Evaluation of the Drift-Barrier Hypothesis
Inverse Scaling Between the Genome-wide Deleterious Mutation Rate and the Effective Population Size
The Three Molecular Lines of Defense Against Mutation
Polymerase Error Rates Are Magnified in Enzymes Involved in Fewer Nucleotide Transactions
Evolution of Recombination Rates
Inverse Scaling of the Recombination Rate / Physical Distance and Genome Size is a Natural Outcome of "One Crossover / Chromosome Arm" Rule
Relative Magnitudes of Recombination c and Mutation u Rates Per Nucleotide Site
Reduced Levels of Variation in Regions of Low Recombination
Summary
Q&A
Thank You