3.3 Survivorship Curves

What does a survivorship curve illustrate?

• The birth rate of a population over time.

• The number of individuals surviving at each age in a cohort.

• The reproductive success of a species.

• The migration patterns of a group of animals.

Which characteristic is typical of a Type I survivorship curve?

• High mortality rates early in life, followed by a slow decline.

• A constant rate of mortality throughout the lifespan.

• High survivorship early and in mid-life, with a rapid decline in old age.

• Very few individuals surviving to adulthood, but those that do live long.

Which type of organisms are typically associated with a Type III survivorship curve?

• Most mammals

• Birds and rodents

• Insects, fish, and plants

• Large, long-lived predators

How should the 'Age' axis on a survivorship curve be interpreted when comparing different species?

• It represents the exact same chronological age for all species.

• It indicates the absolute lifespan in years for each species.

• It shows relative units of age, comparing survival across each species' maximum lifespan.

• It only applies to species with similar average lifespans.

Describe the trend in survivorship shown in this graph. Justify which type of survivorship curve these data represent.