BIOL 1004 Lecture Notes - Lecture 22: Zero Population Growth, Survivorship Curve, Life Table
Document Summary
Density: density results of interplay between processes that add individuals (birth and immigration) and those that remove individuals (death and emigration) Patterns of dispersion: clumped: results as an attraction to a certain resource. Example starfish tend to be found around several other starfish due to localized food sources, and then there will be large areas with no starfish: uniform: often the case in territorial species. Example: emperor penguins: during nesting season, they spread out fairly evenly to be able to care for their eggs and young: random: Includes the age groups, death rate for each and the life expectancy for each: from the data in a life table, a survivorship curve can be created. Types of survivorship curves: type 1: low death rates during early and middle life and increase in death rates among older age groups (ex. Mollusks, since they have many, many offspring but a small fraction of them live to maturity)