View first the 3 types of survivorship curves, and discuss each in terms of lifetime survival, k or r selected species, size, and number of offspring.
Introduce the Malthus hypothesis by examination of both exponential growth curves for population and arithmetic growth curves for food production. Discuss Malthus's conclusion and examine arguments disproving the die off possibility. Outline how humans can alter the carrying capacity to prevent extinction by starvation.
Present in graph form the exponential growth curve for humans, and the linear curve showing food supply. Discuss the Malthusian conclusions regarding how the population will exceed the food supply, leading to die off. Present arguments for and against his proposal, then have the student list and discuss how humans can altert the carrying capacity and prevent die off.
Assignment
module 22
Session Minutes
45
Minutes Student Attended
45
Lesson Comments
Matthew presented some good reasons why a die off would not actually occur.
Review and discuss the logistic growth model and curve and the exponential growth model and curve. Discuss overshoot and die off. Analyze example of lynx and moose population changes through the 1980's and 1990's, along with the effect the canine virus had on both populations, and why. Introduce reproductive strategies, k selected and r selected specie population growth. Examine all factoers which effect both types.
Review K selected species reproduction. Discuss size, maturity, number of offspring, parental care given and intrinsic growth rate. Define and discuss r selected species, view position on a chart compared to k selected. Use examples for each type of reproduction strategy. Evalute survival curves for type 1, type 2 and type 3.
Assignment
complete all uncompleted college board assignments.
Examine the logistic growth model which incorporates environmental limits to describe a population. This model predicts the growth of populations subject to density dependent factors. Introduce overshoot and die off and examine a graph of the effect of predation on a population
Discussion about how populations most commonly increase by reproduction. This leads to the first reproductive strategy which is termed a K selected specie. This specie involves a low intrinsic growth rate which will increase slowly until it reaches the carrying capacity, K . Examine how the K selected species population size is largely determined by the carrying capacity. Humans fall into this category.
Discuss the exponential growth model and the J curve. Introduce the intrinsic growth rate, unlimited resources and ideal conditions for growth. Discuss the J curve from its beginning of the population study to the time designated as the end.
Examine and discuss the intrinsic growth rate model with its potential for population growth accompanied by unlimited resources and ideal conditions. Investigate the effects of high births and low deaths on the intrinsic growth rate. Show a logistic growth rate model and discuss carrying capacity of the ecosystem View a logistic growth rate model curve and identify it as an S curve. Discuss how the model predicts the growth of populations subject to density dependent factors. Introduce overshoot of the carrying capacity and die off.
Run the lab exercise used to estimate a population by the capture, release, and recapture method. Apply the formula to obtain the estimated population by using marked and unmarked lima beans. When finished, review briefly population ecology
Discuss population growth at a given moment. Use diagram to explain the exponential growth model, the J curve. Explain and define population growth rate which includes number of offspring, a definitive time minus the number of deaths.