Biology 1001A Lecture Notes - Parasitism, Demographic Transition, Logistic Function
Document Summary
Characteristics of populations can affect population growth rates. Age structure: a larger base" will have a larger younger population. Potential for rapid future population growth: a stable or equal base will maintain it"s population (zero population. Growth: a narrow base will have negative growth. Summarize survival and reproduction for a cohort of individuals. Type 1: vey little risk of mortality, until you get really old (a fraction of total lifetime). Happens to larger animals, small numbers of offspring, and larger body size. Humans have similar characteristics. (looks like negative exponential) Type 2: for small body animals (birds, mice, etc ) most things are not dying from old age, instead due to nothing with age, for example, dying in a flood. (graph looks like a negative steady decline). Type 3: produces a large number of offspring. Life history: balancing energy or resources given competing demands: growth, reproduction, self-maintenance (repair)