BIO120H1 Lecture Notes - Semelparity And Iteroparity, Monocarpic, Marsupial
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BIO120H1 Full Course Notes
Verified Note
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Document Summary
Used to visualize how number of individuals in a pop decreases with time. Survivorship curves notes: need to identify a cohort (group of individuals of some species in same pop and born at same time) Used to compare generations, populations and different species. Describes the survivorship of the cohort (but survivorship can be different in varying environments: shape of graph can be affected by abiotic and biotic factors (competition, temp) 3 basic patterns: (curves are plotted on a log scale linear scale will look different) Type i survivorship high survival throughout entire life cycle; most individuals die of old age (occurs in stable environments with intense competition) Type ii constant mortality rate over time regardless of age (rodents, adult birds, turtles) Type iii high mortality at young ages; after initial period, survival becomes constant; little parental care (fishes, seeds, marine larvae, octopus) Demography study of characteristics of human pops (births, deaths, growth rates: most countries have type i survival.
