chpt 11&12 key concepts Flashcards
Growth Types
Population Growth
Geometric Growth
Discrete Growth
Exponential Growth
Discrete vs Continuos
discrete- change happens at specific intervals
continous- change happens at every instant
Overlapping vs Nonoverlapping
Over- refer to mating where more than one breeding generation is present at any one time
Non- every breeding generation last just one breeding season
Geometric Growth
Nt = NoLamda^t
-population reproduces at the same time at discrete periods and growth rate does not change
Exponential Growth
Nt=NoE^rot
-an accelerating pattern of increasing population
-unlimited growth
Logistic Growth
r= ro [1 - N/K]
-growth rate gets smaller as population size gets to the maximum of limited resources
-carrying capacity
Limitation
-control of population size with no relation to population size
-Density Independent : it influences birth and death rates but do not regulate population growth
factors:
*temperature
*precipitaiotn
*severe storms
*fires
*floods
*drought
Regulation
-control of population size with relation to population size
-Density Dependent: infraspecific competition inherent in regulation
factors:
*reduced resources availability
*changes in patterns of predation
*spread of disease and parasites
Types of Competition
Intraspecific Competition
-an interaction in a population where members of the same species compete for limited resources
Interspecific Competition
-in which individual of different species compete for the same resources in an ecosystem
Intraspecific Competition Effects On:
-Growth and Development: slower growth/development rates
-Reproduction: decreased fertility/fecundity
-Stress: self thinning in plants
-Dispersal: as competition increases, population density increases. it is considered a density dependant regulation and acts as a negative feedback mechanism
-Territoriality
Allee Effects
when the rate of population growth increases, population density increases (also known as inverse density dependence)
Intrinsic Rates of Increase and Organisms Size
small organisms have higher rates per capita increase
more variable population than large organism
Life Tables
determine how age, size, or life history classes affect the growth of a population
Cohort
follows the survival and reproduction of all members of a cohort from birth to death
Static
show the current probability of death for people of different ages
