BIO220H1 Lecture Notes - Lecture 12: Genetic Variation, Polyculture, Species Richness

• School: UTSG
• Department: Biology
• Course: BIO220H1
• Professor: John Stinchcombe

Document Summary

So far our thinking is: ecology produces selection, leads to changes in allele frequency. Human imposed artificial selection to make crops more nutritious: leads to evolutionary response. Biodiversity results in resistance to environmental perturbation and higher productivity. Top graph: vertical: biomass remaining after drought, horizontal: plant species richness before drought, saturating curve: Plots that started out with higher species richness before drought retained more biomass after drought. Bottom graph: same conclusion true for number of guilds (functional diversity, guild: grasses in one category, legumes in another, shrubs in one category, plots with more guilds had higher biomass. Evidence that diverse communities with lots of species have more resilience than less diverse communities. Establish whether or not genetic diversity in plant community supports more insects. Approach: (1) grow groups of plants that are either monocultures or polycultures: monoculture: grow just 1 genotype (say genotype a) Every individual on this plot is genotype a.