Population Growth Flashcards
Fecundity
Number of offspring produced per year
Generation Time
Average time between birth of individuals and birth of their offspring
Survivorship Curve
Shows survival probabilities with age of population
Life History
Describes when species reproduce, how many offspring are produced, and when it dies
Cost of Reproduction
All life histories reflect trade-offs, reduction in future reproductive potential resulting from present reproductive efforts
Semelparity
Annual plants and most insects focus all resources on a single large reproductive event and then die, likely in short-lived species, those in harsh conditions, those with high reproductive cost like salmon, r-species
Iteroparity
Many species produce fewer offspring per year but reproduce for more years, usually includes more parental care, higher survival of each offspring, K-species
Population Growth
The capacity for growth in any population is exponential
J-Shaped Growth Curve
Populations that grow under ideal conditions produce this type of curve
r
rate of population increase
rmax
occurs when birth rate is max and death rate is min
Carrying Capacity (K)
Maximum population density that can be sustained indefinitely
r-strategies or r-selected
Species have a high rmax, reproduce as fast as possible, usually produce many small, quickly maturing, short-lived offspring, pioneer species
k-strategies and k-selected
Have a low rmax, tend to be long-lived and reproduce later in life, produce few large offspring with protracted parent care (iteroparity)
Density Dependent Factors
Ones that increase as population increases/grows, as population density grows, mortality increases
