Which survivorship curve is typical of species that produce a large number of offspring and experience high juvenile mortality?

Which survivorship curve is typical of species that produce a large number of offspring and experience high juvenile mortality?

• A. Type I
• B. Type II
• C. Type III
• D. None of the above

Answer: (C)

In survivorship curves, a pattern where a large number of offspring are produced but most die before reaching maturity reflects a Type III curve. The key feature is a steep decline in survivorship early in life, due to high juvenile mortality. Those individuals that survive past the vulnerable early stage tend to have a better chance of living longer, so the curve flattens after the initial drop. This strategy fits species that invest little in each offspring but produce many, like many fish, invertebrates, and some plants. By contrast, a Type I curve has low juvenile mortality with high care leading most individuals to old age, and a Type II curve shows a relatively constant mortality risk across ages.

In survivorship curves, a pattern where a large number of offspring are produced but most die before reaching maturity reflects a Type III curve. The key feature is a steep decline in survivorship early in life, due to high juvenile mortality. Those individuals that survive past the vulnerable early stage tend to have a better chance of living longer, so the curve flattens after the initial drop. This strategy fits species that invest little in each offspring but produce many, like many fish, invertebrates, and some plants. By contrast, a Type I curve has low juvenile mortality with high care leading most individuals to old age, and a Type II curve shows a relatively constant mortality risk across ages.