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Resources and population growth

Review your understanding of resources and population growth in this free article aligned to NGSS standards.

Key points:

  • Organisms in an ecosystem need resources to survive. Resources include food, water, oxygen, and shelter. Organisms that get more resources are more likely to grow and produce offspring.
  • A limited resource is one that is not available in endless supply. As populations get bigger, limited resources can start to run out. When this happens, a population’s growth may slow or stop.
  • Organisms often need the same limited resources. This can lead to competition between organisms.
  • Competition can happen between organisms of the same species. It can also happen between organisms of different species.
  • The size of a population depends on the amount of available resources. A population with more resources will likely be larger than a population with fewer resources.
Two young seagulls compete for food. Image credit: “Young gulls fighting over food, Vancouver Island" by Deborah Freeman, CC BY-SA 2.0.

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