Question

1. Differentiate between density-dependent and density-independent factors. Give several examples of each

Answer 1

DENSITY DEPENDENT FACTORS: Any factor that regulates the population in proportion to its density.

Examples:

*competition - once a population exceeds it's habitats carrying capacity, organisms living there have to struggle against one another for scarce resorces.

*Predation - there are many populations that are limited by predation.

* Parasitism - parasites thrive in host population which is densely packed, but if the parasite is too virulent, it will start to deciment the host population.

* Disease - it spreads quickly in densely populated areas where organisms are more close to one another.

DENSITY INDEPENDENT FACTORS: Any factor which is responsible for regulating the population without considering its density.

Examples: natural disasters ( flood, fires, storms, drought, hurricanes ), the weather, pollution . Extreme temperatures can cause decrease in population no matter how large or big the population is.