Chapter 7- Life History

Life History

The schedule of an organism’s growth, development, reproduction, and survival.

Fecundity

The number of offspring produced by an organism per reproductive episode.

Parity

The number of reproductive episodes that an organism experiences.

Parental Investment

The amount of time and energy given to an offspring by its parents.

Life expectancy

The life span of an organism.

Principle of Allocation

The observation that when resources are devoted to one body structure, physiological function, or behavior, they cannot be allotted to another.

Determinate Growth

A growth pattern in which an individual does not grow any more once it initiates reproduction.

Indeterminate Growth

A growth pattern in which an individual continues to grow after initiating reproduction.

Semalparity

When organisms reproduce only once during their life.

Iteroparity

When organisms reproduce multiple times during their life.

Annual Organisms

An organism that has a one-year life span.

Perennial Organism

An organism that has a life span of more than one year.

Senescence

A gradual decrease in fecundity and an increase in the probability of mortality.

Photoperiod

The amount of light that occurs each day; this changes by season and can trigger life history events.