BIO 2129 Lecture 10: October 7, 2016 - Population regulation (density dependence vs. density independence)
7 Oct 2016
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Document Summary
Extinctions are rare (relative to the number of species there are) Population density often fluctuates around reasonably stable values. Density dependent regulation : what population do depend on how big they are. There are factors in the environment that cause them to fluctuate; populations are regulated by. Relationship between population density and the size of clutch. Population densities change relative to what that population size was to start with (discussed in previous lecture via equations) Populations that are sparse and below carrying capacity are likely to grow, populations that are close to carrying capacity are likely to shrink. Mortality rates of trout dependent on population density. If you have huge population densities at the start of the year, a lot do not make it to the end of the year. Population growth rates are proportional to population density. As population density increases, death rate increases and/or birth rates decrease. Population density tends to approach a stable value.
