Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Life history describes the series of events and strategies an organism undergoes from birth to death, including growth, reproduction, and survival. It is shaped by evolutionary pressures to maximize fitness in a given environment.
5 Must Know Facts For Your Next Test
Life history traits include age at first reproduction, number of offspring, and lifespan.
Organisms with r-selected life histories produce many offspring with low survival rates.
Organisms with K-selected life histories produce fewer offspring with higher survival rates.
Trade-offs in life history traits occur because resources are limited; investing in one trait often reduces investment in another.
Semelparity refers to organisms that reproduce once before dying, while iteroparity refers to those that reproduce multiple times throughout their lives.