Mastering Biology Chapter 53
Terms in this set (28)
study of populations in relation to environment and how it influences the density and distribution, age structure and population size
the pattern of spacing among individuals within the boundaries of a population influenced by environment and social factors
influx of new individuals from other countires
the movement of iindividuals out of a population.
number of individuals per area or volume, a result of interplay between processes like birth, death, immigration and emigration.
individuals aggregate in patches, may be influenced by resource availability and behaviour
individuals are evenly distributed, may be influenced by social interactions like territoriality
position of individuals occurs independently of the positions of other individuals, occurs in the absence of strong attractions or repulsions
study of vital statistics like birth and death rates, age distributions, gender, etc. and how they change over time.
an age-specific summary of the survival pattern of a pop. best made by following a cohort
a group of individuals of the same age.
graphic representation of data in a life table
age-specific summary of the reproductive rates in a population which describes the reproductive patterns of the females of the population.
the traits that affect its reproductive and survival schedule, involves reproductive age, frequency of reproduction and number of offspring per cycle.
"big-bang" reproduction, reproduce once then die. Favored in unpredictable environments.
repeated reproduction, favored in dependable environments
life history "trade-offs"
balance of use of resources between survival and reproduction - eg many tiny seeds vs. a few large meaty ones
Per capita rate of increase
an idealized exponential growth model. Change in population = births + immigrants - deaths- emigrants (if immigration and emmigration are ignored, equals birth rate minus death rate. ) over time.
exponential population growth
pop. increase under idealized conditions where reproduction is at max or "intrinsic rate of increase". Results in a J-shaped curve. Cannot be sustained in life due to limitations in resources
Maximum population an environment can sustain
logistic growth model
Model showing a slowing of population growth as it reaches carrying capacity, producing an S-shaped curve. Fits few real pops but useful in estimating possible growth
when individuals of a population find it harder to survive or reproduce if the population size is too small.
birth and death rates are unaffected by population density
a negative feedback where birth rates fall and death rates rise with rise in population density. Affected by resource competition, territoriality, disease, predation, waste toxicity and intrinsic factors (such as goldfish growth regulation)
the study of the complex interactions between biotic and abiotic factors that cause variation in population size.
a transition from population stability caused by correspondent high birth and death rates to population stability caused by low birth and low death rates - due to increased education, improved access to health care, especially for women.
relative number of individuals at each age, this can predict a population's growth trends, reflects social conditions and help plan for the future.
the land and water needed to sustain a population.