Summary
r-strategists reproduce quickly with many offspring; K-strategists have few offspring and invest heavily in each.
In depth
r-selected species (insects, weeds, bacteria) live in unstable environments with early maturity and many small offspring. K-selected species (elephants, humans) live in stable ones with later maturity, few offspring and parental care. Most species lie on a continuum.
It is a continuum and many species are intermediate. Life history theory expands the idea with age at maturity and parental care.
Remember: r-selected species do well in disturbed habitats; K-selected in stable ones.
Frequently asked questions
What is r and K Strategies?
r-strategists reproduce quickly with many offspring; K-strategists have few offspring and invest heavily in each.
Which area of biology covers r and K Strategies, and how advanced is it?
r and K Strategies is one of the 54 topics in Ecology. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Ecological Succession, Survivorship Curves, Exponential Growth.
Can you give an example of r and K Strategies?
A dandelion versus an oak.
What should I learn before r and K Strategies?
Work through the Beginner topics in Ecology first, such as Ecology, Ecosystem, Biotic and Abiotic Factors, then return to r and K Strategies. Intermediate topics assume the Beginner vocabulary.
What topics are related to r and K Strategies?
The closest topics to r and K Strategies are Ecological Succession, Survivorship Curves, Exponential Growth, Island Biogeography. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand r and K Strategies?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for r and K Strategies. To practise the whole of Ecology, use the Ecology quiz.
How is r and K Strategies different from Ecological Succession?
r and K Strategies: r-strategists reproduce quickly with many offspring; K-strategists have few offspring and invest heavily in each. Ecological Succession: The gradual, directional change in a community over time, primary on bare rock and secondary after disturbance. Read both side by side and note what each one explains.
How should I study r and K Strategies step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Ecological Succession and explain the difference aloud. Finally, take the Ecology quiz and come back to this page for any question you miss.