What distinguishes r-selected species from K-selected species?

R-selected species are characterized by their reproductive strategies that prioritize high reproductive rates to ensure survival in unpredictable environments. These species tend to produce a large number of offspring but often invest little to no parental care, which allows them to take advantage of favorable conditions and quickly increase their population size. This reproductive strategy is beneficial in unstable environments where the mortality rate is high, as it maximizes the chances that some offspring will survive despite the odds.

In contrast, K-selected species typically operate in more stable environments, where competition for resources is intense. They produce fewer offspring but invest significantly more time and energy into raising them, leading to a higher survival rate for each individual. This strategy is associated with traits such as longer gestation periods, extended parental care, and greater investment in offspring quality.

The other options do not accurately reflect the distinctions between r-selected and K-selected species. For example, K-selected species do not necessarily have larger population sizes; they usually have stable or lower numbers than r-selected species, which can boom rapidly. Additionally, r-selected species can vary greatly in size, and the relationships between resilience to predators and these reproductive strategies are complex and not a defining characteristic.