The concept of evolution is not necessarily tied to the existence or extinction of a species. Evolution is an ongoing process that occurs over long periods of time and encompasses changes in the heritable traits of populations of organisms. It is driven by various factors such as genetic mutations, natural selection, genetic drift, and gene flow.
If a species does not go extinct, it means that it has successfully adapted to its environment and persisted over time. However, this does not imply that the species will continue to undergo significant evolutionary changes indefinitely. Evolution is a dynamic process influenced by a multitude of factors, including environmental changes, competition, and genetic variations within a population.
Over time, a stable environment may lead to a relatively stable set of selective pressures, resulting in less pronounced evolutionary changes in a species. This could lead to a period of relative evolutionary stasis or slow change. However, even in stable environments, genetic mutations and other evolutionary mechanisms can still introduce gradual modifications and adaptations over long periods.
Additionally, it's important to consider that evolution does not have a predetermined endpoint or goal. It does not necessarily lead to more complex or "advanced" organisms. Evolution is driven by the interplay of various factors and can result in a wide range of outcomes depending on the specific circumstances and selective pressures acting on a species.
In summary, while the persistence of a species indicates its successful adaptation to its environment, it does not guarantee indefinite or constant evolution. Evolution is an ongoing process influenced by numerous factors, and its trajectory can vary depending on environmental conditions, genetic variability, and other factors.