Bio lecture 2: evolution: microevolution: genetic changes within populations. All life, past and present are connected by one ancestor. Biological evolution is when there is a change in allele frequency in the population. The genetics change over time in the population. Micro evolution is when there is changes in species at a small scale. Population is when individuals of species are at the same place at the same time. Example of microevolution under strong natural selection is antibiotic resistance. Phenotypic variation is the variety in phenotypes that exist in a population. Phenotypic plasticity is when an organism has the ability to change its phenotype due to environmental factors. There are two types of phenotypic variation: quantitative variation and qualitative variation. Quantitative variation can be measured and controlled by multiple genes. Qualitative variation is difficult to measure and have characteristics with distinct states. Polymorphism is distinct and has different variations of characteristics.