BIS 2B Lecture Notes - Lecture 21: Ecological Speciation, Biogeography, Niche Differentiation

• School: UC-Davis
• Department: Biological Sciences
• Course: BIS 2B
• Professor: strauss,gerhart

Document Summary

Origin - cause of large scale biogeographic patterns in diversity. Speciation + dispersal (immigration) - extinction + ecological coexistence. Coexistence can occur b/c species specialize on different resources, habitat, or time of season to minimize comp overlap. Disturbance mediated coexistence: tradeoff between r-selected colonizers in high disturbance and k-selected competitors. Paradox of plankton: studied how many different types of plankton coexist. Plankton communities are very dynamic, not homogenous/constantly changing so one species is always in dominance. More sunlight in these areas allows for more resources which giver more food to support more species (ecological diversity on these resources) Net primary production(higher): rate that biomass/energy accumulates minus what is lost by respiration. Rate of ps - rate of respiration = npp. Species packing due to sister species being able to share different parts of niche of niche. This isn"t always true b/c paradox of enrichment means adding nutrient usually decreases diversity.