Ecologists use survivorship curves to analyze patterns of mortality in different species.
These curves illustrate the proportion of individuals in a population that survive at different ages.
Scientists conducted a long-term study on four different species and recorded their mortality rates over time.
The graph below presents their findings.
Survivorship Data for Four Species

Identify which survivorship curve (A, B, C or D) represents a species that produces many offspring with low parental care.
Identify the name of the type of survivorship curve that represents species that produce many offspring with low parental care.
Researchers collected additional data on the reproductive strategies of the four species shown in the graph.
Describe how the reproductive strategy of a species with a Type I survivorship curve differs from that of a species with a Type III survivorship curve.
Ecologists studying the population dynamics of the Type II species observed that mortality remained relatively constant across all life stages.
Explain why species with a Type II survivorship curve have relatively constant mortality rates throughout their lives.
The researchers expanded their study to examine population growth trends in a mammal species exhibiting a Type I survivorship curve.
Identify whether this species is more likely to be K-selected or r-selected.
The researchers hypothesize that environmental changes, such as habitat destruction, may impact the survival of K-selected species.
Identify the independent variable in a study investigating how habitat destruction affects K-selected species.
Identify the dependent variable in the same study.
Scientists design an experiment to test how changes in food availability impact survivorship in a population of a Type I species.
Describe an appropriate control for this experiment.
Identify a testable hypothesis for the experiment described in part (h).
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