Contributor: Hannah Brooks. Lesson ID: 12968
Did you know that space and disease can limit population growth? You will be amazed at the different environmental factors that could be keeping your favorite things from taking over the world!
They seem to be everywhere — especially on rocky beaches. The fact is, barnacles can live in almost any environment.
Barnacles are found on shorelines, rocks, and boats. They're attached to shells, and even riding on whales!
That is because they have a need to attach to things in order to live.
This need to attach limits the ability of barnacles to take over because there are only so many surfaces available. Space, therefore, is defined as a limiting factor for barnacles. Every population of organisms is limited by certain aspects of their environment. These factors prevent too many of the organisms from exploiting the area of natural resources.
Barnacles are just one of many different organisms that can appear in great numbers. However, just like space is a limiting factor for barnacles, every population is limited by certain aspects of their environment.
There are two types of limiting factors: density dependent and density independent.
Think about what the term density broadly means: the amount of material in a given volume or area. For populations of organisms, density can be defined as the number of living things in a given area, like the number of white-tailed deer in a meadow or the number of great white sharks in a particular region of the ocean.
You may have mentioned things like the number of mice or squirrels living in the local area, or the number of trees that are available for nesting sites. These are all factors that limit the number of hawks and would be considered density dependent limiting factors because they depend on the number of hawks competing for the same resources.
Density dependent limiting factors can include food resources, the availability of shelter, local water sources, number of predators, and the spread of infectious diseases.
Density independent limiting factors impact the entire population regardless of the number of organisms in the area.
Things like forest fires, floods, and ocean acidification, are all examples of density independent limiting factors. When a forest fire occurs in an environment, it eliminates members of the population based on their location, not the density.
Small-scale climate changes, like an increase or decrease in average temperature or rainfall, can also impact the number of organisms in an area.
Watch Population Limiting Factors | Biology, from Course Hero for more information on this:
Density independent and density dependent limiting factors keep local populations regulated. This balance is important in creation because it prevents the destruction of local areas due to overpopulation.
List a few density dependent and density independent factors that would influence the success of plants in a garden.
In the Got It? section, you will practice sorting images and statements into density independent and density dependent limiting factors based on key ideas from this section!