Short URL

Overlay species & human population

 

Other Human Population areas:

Loading, please wait...

Human population correlated with species richness of birds at risk

    The "overlay scores" function calculates correlation between foreground and background screen scores and plots them together.  Worldmap supports three comparative techniques:

    1. Comparing two presence maps - plotted in three colors, one for each species and a third for cells in which both species occur together. 

    2. Comparing a presence and a quantitative map, such as presence and richness - a color scale represents richness with black cells representing occurrence.

    3. Comparing two quantitative maps, such as the human population and richness shown here (see Williams and Gaston 1998) - two color scales are combined. Increasing intensity of green represents increasing human population densities; increasing intensity of blue represents increasing densities of bird species at risk. Black corresponds to low human densities and low densities of bird species at risk, white to high levels of both parameters.