BIOLOGY 2F03 Lecture Notes - Lecture 11: Survivorship Curve, Life Table, Dall Sheep
26 Nov 2016
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Document Summary
Population structure can be defined by a number of factors including patterns of mortality, age distributions, sex ratios and dispersal. A survivorship curve summarises the pattern of survival in a population. Patterns of survival vary a great deal from one species to another. Some species produce young in the millions, which die off at a higher rate while others produce few young, and invest heavily in their care. Ecologists use bookkeeping devices called life tables that list the birth, the survivorship, and the deaths or mortality in populations. There are three main ways of estimating patterns of survival within a population. 1st and most reliable way is to identify a large number of individuals that are born at about the same time and keep records on them from birth to death. A group born at the same time is called a cohort and a life table made from data collected in this way is called a cohort life table.
