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Natural History – The branch of Biology concerned with describing what exists in nature (i.e., primarily observational a

Natural History – The branch of Biology concerned with describing what exists in nature (i.e., primarily observational and not experimental) (Freeman, 2005)

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Natural History – The branch of Biology concerned with describing what exists in nature (i.e., primarily observational a

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  1. Natural History – The branch of Biology concerned with describing what exists in nature (i.e., primarily observational and not experimental) (Freeman, 2005) Life History – The sequence of events in an individual’s life, from birth to reproduction to death. Also the study of how the organism allocates resources and energy to these different activities. (Freeman, 2005) Life Table – A data set that summarizes the probability that an individual in a certain population will survive and reproduce in any given year over the course of its lifetime. (Freeman, 2005)

  2. Life Table – A data set that summarizes the probability that an individual in a certain population will survive and reproduce in any given year over the course of its lifetime. Survivorship – the proportion of offspring produced who survive to a given age.

  3. Survivorship – the proportion of offspring produced who survive to a given age. Survivorship curves – show how survivorship changes over the course of a cohorts lifetime.

  4. Fecundity – the number of female offspring produced by each female in the population. The age at which reproduction starts can have big effects on population growth

  5. Life history trade-offs Individuals have a limited amount of energy to invest in reproduction. You can either produce a lot of small eggs or a few large eggs. Individuals have a limited amount of energy to invest in reproduction. Species with high fecundity usually have low survivorship. Species with low fecundity usually have high survivorship.

  6. If a population growth rate is constant, population growth (change in numbers over time) will be exponential. rmax = intrinsic rate of increase = growth rate of a species with unlimited resources.

  7. Exponential growth can not go on forever As resources become scarce, birth rate drops and death increases. Population size will reach asymptote This is the logistic growth curve. Carrying capacity (K) -The point where no more individuals can be supported by the environment.

  8. Exponential growth can not go on forever Why do birth rate and death rate change? Survivorship and fecundity are density dependent – they decline at high density

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