BIO120H1 Lecture Notes - Lecture 6: Net Reproduction Rate, Survivorship Curve, Fecundity
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BIO120H1 Full Course Notes
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Age structure: the distribution of individuals among age classes within a population. Fecundity: the number of offspring produced per reproductive episode: reproductive period usually preceded by resource-accumulation phase, fecundity-survivorship trade-offs = cost of reproduction. Type ii survivorship curve constant survival rate with age. Type i survivorship curve high survival rate at the beginning, falls off abruptly with age as the age-specific mortality rate increases (human; mortality is low early in life and then increases rapidly later in life) . Type iii survivorship curve high mortality rate in early life, survival rate increase later in life. (fishes; young individuals are extremely vulnerable to predation and other risk factors, which they escape as they grow larger and mature). Generation time (t): the average period between the birth of an individual and the birth of its offspring; average age at which a female gives birth: this is a formula for a weighted average. Since ( ) ( ) , then,
