Which of the following statements regarding survivorship types is true?

Type II survivorship is defined by a constant mortality rate throughout the life span of an organism. This means that individuals have an equal chance of dying at any age. This is often visualized in a straight line when graphed, indicating consistency in survivorship regardless of the age of the organisms. Organisms exhibiting Type II survivorship tend to experience a steady decline in numbers, which suggests that environmental factors affect mortality uniformly across ages.

In contrast, Type I survivorship involves high survival rates during early and middle life, with a dramatic increase in mortality in older age groups, characteristic of many large mammals. Type III survivorship is marked by high mortality rates in the early stages of life, with few individuals reaching adulthood, commonly seen in species that produce many offspring but invest little care in them, such as many fish and some plants. Thus, the statement about Type II survivorship accurately reflects its defining characteristics within the context of survivorship curves.