Biological Population Densities
Population density is population divided by total land area or water volume, as appropriate.
Low densities may cause an extinction vortex and lead to further reduced fertility. This is called the Allee effect after the scientist who identified it. Examples of the causes in low population densities include:
- Increased problems with locating sexual mates
- Increased inbreeding
Different species have different expected densities. R-selected species commonly have high population densities, while K-selected species may have lower densities. Low densities may be associated with specialized mate location adaptations such as specialized pollinators, as found in the orchid family (Orchidaceae).
Read more about this topic: Population Density
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