Summarizing Life Histories and Natural Selection

Summary

All species have evolved a pattern of living, called a life history strategy, in which they partition energy for growth, maintenance, and reproduction. These patterns evolve through natural selection; they allow species to adapt to their environment to obtain the resources they need to successfully reproduce. There is an inverse relationship between fecundity and parental care. A species may reproduce early in life to ensure surviving to a reproductive age or reproduce later in life to become larger and healthier and better able to give parental care. A species may reproduce once (semelparity) or many times (iteroparity) in its life.

Glossary

energy budget

allocation of energy resources for body maintenance, reproduction, and parental care

fecundity

potential reproductive capacity of an individual

iteroparity

life history strategy characterized by multiple reproductive events during the lifetime of a species

life history

inherited pattern of resource allocation under the influence of natural selection and other evolutionary forces

semelparity

life history strategy characterized by a single reproductive event followed by death