Final answer:
R-selected species ensure their survival through a reproductive strategy of producing many small offspring that are mature and self-sufficient at birth, such as jellyfish and dandelions. They thrive in unpredictable environments by playing the odds that some offspring will survive without intensive parental investment.
Step-by-step explanation:
R-selected species are characterized by their reproductive strategy to produce a large number of small offspring. This approach is advantageous in unpredictable or changing environments, where the odds of survival for each individual offspring are low. Therefore, having many offspring increases the chances that some will survive.
Examples of r-selected species include marine invertebrates like jellyfish, which release vast numbers of larvae into the ocean, where most will not survive to adulthood. Another example is the dandelion, a plant that produces numerous wind-dispersed seeds. Despite the low energy content in each seed, the sheer number of seeds increases the likelihood that some will land in a hospitable environment and germinate.
Unlike K-selected species, which invest substantial resources into a few offspring with longer developmental times and parental care, r-selected species invest minimally in each offspring. The offspring of r-selected species are relatively mature and self-sufficient at birth or hatching.