Mitch Lange Jack Connor Kelly Goehring pg

 Studying populations in relation to the environment…  Environmental influences, on population density, distribution, age structure, and population size With more of these guys… There will be less of these guys fsV4PsAeGIo/TaTBsK4pY9I/AAAAAAAAAjE/hbD sJ0IRVik/s1600/lone%2Bseal2_for%2Bblog jpg lI0g2NzaOJ8/Tf4udjOH9oI/AAAAAAAAAFo/ CTZ0kaz0DAA/s1600/utah-hunting.jpg

Population size can be determined in a number of ways: Like number of nests, burrows, tracks, or poop Additions to population occur from : ches-flying01ll.jpg wtF8KmDWI/AAAAAAAAAak/xfpC4cpyqTU/s 400/il_fullxfull_ jpg Population Size Immigration Births

 Animals leave because of: Deaths&Emigration: Movement of animals out of a population jpg

 3 types: Dispersion-L.jpg d/media/ch53/53_04cRandomDispe rsion-L.jpg 53/53_04bUniformDispersion-L.jpg Clumped: Most common, with individuals in separate patches Uniform: Evenly spaced, with patterns resulting from interactions Random: Unpredictable Spacing

 Vital Statistics of populations and their change over time  Particularly looking at birth rate and death rates  Life Table  Age that a person/animal is expected to live to  Cohort= group of individuals of same age. Used to follow the fate from birth to death Survivorship Curve Plot to see which data points in a cohort are still alive p.gif/ /survivorship.gif

 Some species reproduce in a one shot chance called semelparity  If offspring survival rate is low, this is favored  Others reproduce in the annual cycle called iteroparity  More favorable when there is dependable environment and might be competition for resources  There are many trade-offs between reproduction and survival:  High mortality rates in offspring often exhibit large number of small offspring  High predation rates also factor into large numbers of offspring n_ur_biodiversiteh.jpg

 Per Capita Rate of Increase is the amount a population goes up over time  Deaths>Births is declining population  Births>Deaths is growing population  Births=Deaths is zero population growth  Intrinsic rate of increase or r max is when the per capita rate of increase is at its maximum 1moI/AAAAAAAAC8E/IYtb9e0- wgE/s1600/maps%2B-%2Bcensus%2B- %2BUS%2Bpopulation%2Bgrowth%2Bsince%2B17 90.png

 With more population density, each individual has access to fewer resources  The carrying capacity is the max population an environment can support  In this model, the per capita rate of increase declines as carrying capacity is reached  The graph of most real populations is like an S shape  When the population increases to it there is a lag in time where the population can resettle content/uploads/2009/05/logistic.jpg

Density Dependency Death rate rises as population density rises Also a birth rate falling with rising density Density Independency Birth rate or death rate does NOT change with population density

 Competition for Resources  More population more competition  Territoriality  Territory space is what the animals compete for i.e: nesting sites  Health  Transmission rate of a disease can wipe out a population  Predation  More food captured means lowered population  Toxic Wastes  Intrinsic Factors  Physiological effects of things like over-reproduction marking-300.jpg /2011/09/toxic-waste.jpg

 Population Dynamics  Metapopulations  Population Cycles = predictable intervals iffeSlide1.gif

 1962-no longer y^x  Demographic Transition  Developed countries: reproduction rates about = replacement level  Population growth in Developing countries

 Relative number of individuals at each age

 Some say a billion, some say a trillion  Ecological Footprint( EF)  Produce all resources, absorb all wastes  Ecological Capacity( EC)  Actual resource base of their country  U.S. EF= 8.4 ha, EC= 6.2 ha  World EF= 1.7 ha

 Space  Nonrenewable Resources  Renewable Resources  Earth’s Capacity to Absorb Wastes