How does population density affect organisms in an ecosystem and does a large population preserve genetic diversity more than a small population?
When a population reaches a high density, there are more individuals trying to use the same quantity of resources. This can lead to competition for food, water, shelter, mates, light, and other resources needed for survival and reproduction.The increase in population increases the density, leading to scarcity of resources. This leads to competition in the ecosystem, which impacts survival and reproduction. If one animal's population increases, the population of animals that eat that animal might also increase. Increases in population aren't always good. Sometimes a population will grow too large for the environment to support. Other changes in limiting factors can cause a population to decrease. Human population growth impacts the Earth system in a variety of ways, including: Increasing the extraction of resources from the environment. These resources include fossil fuels, minerals, trees, water, and wildlife, especially in the oceans. Individuals make up a population; populations make up a species; multiple species and their interactions make up a community; and multiple species and their interactions make up ecosystems when you include the abiotic factors. Genetic diversity generally underpins population resilience and persistence. Reductions in population size and absence of gene flow can lead to reductions in genetic diversity, reproductive fitness, and a limited ability to adapt to environmental change increasing the risk of extinction.Distribution is one way that genetic variation can be preserved in large populations over wide physical ranges, as different forces will shift relative allele frequencies in different ways at either end. Higher population genetic diversity in the abundant species is likely due to a combination of demographic factors, including larger local population sizes, faster generation times and high rates of gene flow with other populations. Maintaining high genetic diversity allows species to adapt to future environmental changes and avoid inbreeding. Inbreeding, which happens when there are small, isolated populations, can reduce a species' ability to survive and reproduce.
- Badges
- Science topic