Survivorship curves illustrate:

Survivorship curves are graphical representations that illustrate the proportion of individuals within a population that survive to different ages. They provide valuable insights into the life history and survival patterns of a species across different stages of life. These curves are typically classified into three main types—Type I, Type II, and Type III—each reflecting distinct survival strategies and risk of mortality at various life stages.

For instance, a Type I curve, which is characteristic of species such as humans or some large mammals, indicates high survival rates during early and middle life, followed by an increase in mortality in older age groups. Conversely, a Type III curve, seen in species like many fish or amphibians, reflects high mortality rates early in life but higher survival rates once individuals reach a certain age or size.

By illustrating these patterns, survivorship curves help ecologists and biologists understand the dynamics of population survival, which can be influenced by various factors including environmental conditions, reproductive strategies, and ecological niches.