What are the characteristics of r-selected and K-selected species?

R-selected species are characterised by rapid growth and high reproduction rates, while K-selected species have slower growth and lower reproduction rates.

R-selected species are typically found in unstable or unpredictable environments. They are characterised by a high growth rate, early maturity, and a high capacity for reproduction. These species often produce a large number of offspring, but invest little energy in each individual. This strategy is advantageous in environments where resources are plentiful but unpredictable, as it increases the chances that at least some offspring will survive. Examples of r-selected species include insects, rodents, and weeds.

On the other hand, K-selected species are typically found in stable or predictable environments. They are characterised by a slower growth rate, later maturity, and a lower capacity for reproduction. These species often produce a smaller number of offspring, but invest a significant amount of energy in each individual. This strategy is advantageous in environments where resources are limited but predictable, as it increases the chances that each offspring will survive to maturity. Examples of K-selected species include elephants, humans, and whales.

The terms 'r-selected' and 'k-selected' come from the ecological concept of r/K selection theory. In this theory, 'r' represents the intrinsic rate of natural increase of a population, while 'K' represents the carrying capacity of an environment. R-selected species are adapted to exploit environments far below the carrying capacity, while K-selected species are adapted to thrive at or near the carrying capacity.

It's important to note that r/K selection is a spectrum, not a binary distinction. Many species exhibit characteristics of both r-selection and K-selection to varying degrees, depending on the specific environmental conditions they encounter. For example, a species may exhibit r-selected characteristics in an early successional environment, but K-selected characteristics in a late successional environment. This flexibility allows species to adapt to changing environmental conditions and contributes to the diversity of life on Earth.