1 / 8

Population Dynamics: Growth and Limiting Factors

Explore how populations grow in predictable patterns and the factors influencing their size, such as births, deaths, immigration, and emigration. Learn about exponential and logistic growth, carrying capacity, population crashes, and the impact of ecological factors on population dynamics.

martad
Download Presentation

Population Dynamics: Growth and Limiting Factors

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. KEY CONCEPT Populations grow in predictable patterns.

  2. Changes in a population’s size are determined by immigration, births, emigration, and deaths. • The size of a population is always changing. • Four factors affect the size of a population. • Immigration – the movement of individuals into one population from another. • Births – increase the number of individuals in a population. • Emigration – the movement of individuals out of a population and into another population. • Deaths – decrease the number of individuals in a population.

  3. Population growth is based on available resources. • Exponential growth is a rapid population increase due to an abundance of resources. Fig. In Australia during the early 1900s, the introduced European rabbit population exhibited exponential growth. Formula for calculating exponential growth: y=abx y= population # a= # of females x= # of years (generations) b= # of offspring/female

  4. Logistic growth is due to a population facing limited resources.

  5. Carrying capacity is the maximum number of individuals in a population that the environment can support. • A population crash is a dramatic decline in the size of a population over a short period of time.

  6. Ecological factors limit population growth. • A limiting factor is something that keeps the size of a population down. • Density-dependent limiting factors are affected by the number of individuals in a given area. Fig. Taking down prey as large as a moose requires that the members of a pack work together. As many as ten wolves may take hours or even days to wear down this moose.

  7. predation • competition • Density-dependent limiting factors are affected by the number of individuals in a given area. • parasitism and disease

  8. unusual weather • natural disasters • human activities • Density-independent limiting factors limit a population’s growth regardless of the density. Fig. The storm surge accompanying a hurricane can cause dangerous flooding.

More Related