WFSC 403 1st Edition Lecture 7 Outline of Last Lecture I Population Projections II Evolution of Demographic Traits III Static Life Tables Outline of Current Lecture I Evolution of Demographic Traits a Two Caveats II Composition of Populations a Page 139 in the textbook III Chapter Organization of Chapter 9 IV Types of Populations Growths a Exponential and Logarithmic Current Lecture Essay on page 131 o Summarizes demographic projections and how to interpret them o Simulation model point The author says we can t predict the future so why do we try We are human and wish we had the ability to predict the future What use are the projections Quantify and qualify data We are embracing uncertainty and try to quantify the data that we have Page 151 figure 9 10 o Whooping Crane populations o When we projected did we get the same numbers We did not because we did not have any limiting factors Now a days cranes are in the high 200 Graphs and populations can not realistically be exponential forever It will level off and become logarithmic Population projections always have some value and use o To show how wrong off they are o To give an idea of how the populations should grow The Caveats These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute o If Dr Grant told us to go and figure out the fox squirrel population what would we need to do Defining the populations Counting what to count how to mark these are all problems in the real world Other issues are how are the age specific birth and death rates affected by other communities Do skunks use resources do hawks and dogs prey on the squirrels Disease and parasitism o Comparing populations Different age specific birth and death rates and different sexes o Two faces of population ecology The first at the population level The second recognizing that the results of one individual isn t how all of the population should be considered Disney World example o Many years ago Landscape Ecology Society and the Ecology Society met in Disney World The keynote speaker talked about the exponential growth of Orlando after Disney World was constructed Frank Golly a well known ecologist asked what the speaker thought the limiting factor for Orlando would be The speaker said that there would be no limiting factor This blew the ecologists minds Why did he tell us this story Are there such things as unlimited growth A quote was once said that business grows or it will die o Another example was that a friend of Dr Grants once said that the resources that New York City must draw in must be a lot A gentleman from New York City said that No New York sends out a lot of resources As future ecologist we should believe in limiting resources and also know which resources we are talking about Exponential growth comes from an unlimited environment o This is unrealistic for a long time S shape graphs which is known as logarithmic or density dependent limited There are two kinds of populations o Non overlap generations Big Bang reproduction They reproduce and then die Discrete o Population overlap Repeat reproducers
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