Unit 4 Pt 1 Flashcards
Population dynamics
Population change due to population size, population density, population dispersion, age structure
Population Equilibrium
deaths=births
Natality
number of individuals added through reproduction
Fecundity
physical ability to reproduce
Fertility
measure of the actual number of offspring produced
Survivorship
percentage of a cohort that survives to a certain age
Density Dependent
factors that change based on population density
Density Independent
factors not affected by population
Positive growth
pyramid shape
Zero Growth
Vertical edages
Negative growth
inverted pyramid
Biotic Potential
factors allow a population to increase under ideal
conditions
Environmental Resistance
affect the young more than the elderly in a population,
thereby affecting recruitment
Replacement Level
when recruitment (young) = adults that have died
Recruitment
survival to reproductive age
Exponential growth
J-shaped curve (only happens when a disturbance
occurs– foreign species, habitat change, removal of predators)
Carrying capacity (K)
maximum number of individuals a habitat can support
Logistic Growth
S-curved growth curve, population
growth decreases as density reaches carrying capacity
Critical Number
minimum number of individuals a
species needs to stay a healthy population
r - Strategists
spend most of their time in exponential growth, maximize reproductive life, minimum life
K - Strategists
maximize lifespan, produce less young, live longer
Late Loss
K-strategists, produce few young & care for
them until they reach reproductive age
also called Type I
Constant Loss
intermediate reproductive strategies with fairly constant mortality
also called Type II
Early Loss
r-strategists with many offspring, high infant mortality and high survivorship
also called Type III
