BIO205H5 Lecture Notes - Lecture 7: Pair Bond, Altricial, Semelparity And Iteroparity

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5 Feb 2015

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Lecture 7 - life histories: there are a large range of life histories due to different adaptations. Bio205 for different niches, parental involvement, etc: as fecundity increases (the number of offspring), adult survival rates decrease. In other words, you can have a few large offspring which live long, or many small offspring which die after a short lifespan. Each strategy involves trade-offs, as energy expended on reproduction is not available for growth or maintenance. The bigger the tree, the fewer offspring it has. This has a similar trade-off as the goldenrod plant. The more seeds if produces, the lower the quality of the seed. A trade off in reproduction is in terms of offspring size vs. offspring number: another example is the european kestrels. The larger the brood, the more time and energy the parents use to find resources for the chicks, so the adults themselves have a lower life expectancy. They are sacrificing their life to feed their children.