Why are perennial plants typically associated with Type II survivorship curves?

Perennial plants are indeed typically associated with Type II survivorship curves because they exhibit a consistent mortality rate throughout their lifespan. In a Type II survivorship curve, organisms have a roughly equal chance of dying at any age, which is characteristic of many perennial plants. This means that while they may experience some mortality at different life stages, the risk does not dramatically increase or decrease as they mature.

This relationship reflects the ecological strategy of perennials, as they often invest energy in growing for multiple seasons and can withstand various environmental stressors over time. Unlike organisms with Type I or Type III curves, where mortality rates shift significantly from early to late life, perennials maintain a steady risk throughout their lifespan, making them an excellent example of a Type II survivorship strategy.