Chapter 53 Population Ecology -Biological processes influence population dynamics, dispersion, and demographics -Traits of the natural world are products of natural selection -Exponential vs logistic growth -Many factors of population growth are density dependent -Human population growth is no longer increasing exponenetially but still increasing rapidly

Population – Group of a single species living in the same general area. Population Ecology – Study of biotic and abiotic factors influence the density, distribution, size and age structure of populations. Dispersion of individuals 1. Clumped (Common Resource) 2. Uniform (Caused by Antagonistic relationships - Territorial) 3. Random (Not common)

Demographics – Study of vital stats of a population 1.Life Table – Age specifics 2.Survivorship Graphs 3.Reproductive Rates What are some conclusions from the graphs shown?

Life History – Compilation of living organism’s successful traits, most importantly, reproductive schedule. 1. When reproduction begins 2. How many offspring are produced in one event 3. How often organisms reproduce (Once in a lifetime vs every year) *Humans don’t follow this instinctive pattern. Life History are evolutionary outcomes NOT conscious decisions be the organisms. Once/Lifetime

Exponential Population Growth *Ideal conditions (enough resources) -Rarely occurs naturally -Takes into account birth rate vs death rate -R-max is the highest rate of reproduction afforded to a species and dictated by their individual life histories. Logistic Population Growth or Density Dependent *When the death rate goes up and/or the birth rate goes down. -Pred/prey relationships -Lack of or Competition for resources (reach carrying capacity) -Territory Competition -Draw a Preditory Prey Graph K Selection = Density Dependent strategists R Selection = Increase in Reproductive success K – Max

Write a conclusion for each graph pertaining to the human population Why is the percent increase going down?