Chapter 53 Ap Bio

Chapter 53 Ap Bio

__________ _________ explores how biotic and abiotic factors influence the density, distribution, size, and age structure of populations.
Population ecology
A ___________ is a group of individuals of a single species living in the same general area. members of a population rely on the same resources, are influenced by similar environmental factors, and are likely to interact and breed with one another.
population
A __________ _____________ may be natural ones, as in the case of an island or a lake, or they may be arbitrarily defined by and investigator.
population’s boundaries
The ________ of a population is the number of individuals per unit area or volume. It is not a static property but changes as individuals are added to or removed from a populations
density
__________ is the pattern of spacing among individuals within the boundaries of the population.
Dispersion
Ecologists also use the _____-_______ ___________ to estimate the size of wildlife populations
mark-recapture method
Additions occur through birth and _____________, the influx of new individuals from other areas.
immigration
The factors that remove individuals from a population are death and __________, the movement of individuals out of a population and into other locations.
emigration
The most common pattern of dispersion is ________, in which individuals are aggregated in patches.
-plants and fungi are often like this where soil conditions and other environmental factors favor germination and growth
clumped
A _________, or evenly spaced, pattern of dispersion may result from direct interactions between individuals in the population.
uniform
Animals often exhibit uniform dispersion as a result of antagonistic social interactions, such as _____________, the defense of a wounded physical space against encroachment by other individuals.
territoriality
____________ patterns are rarer than ____________ patterns.
Uniform, clumped
In ___________ dispersion, the position of each individual in a population is independent of other individuals.
random
_________________ is the study of the vital statistics of populations and how they change over time.
-particular interest are birth and death rates
Demography
A useful way to summarize some of the vital statistics of a population is to make a ________ ________.
life table
Demographers developed ______ __________, age-specific summaries of the survival pattern of a population.
life tables
The best way to contract a life table is to follow the fate of a _________, a group of individuals of the same age, from birth until all of the individuals are dead.
cohort
A graphic method of representing some of the data in a life table is a ____________ ___________, a plot of the proportion or numbers in a cohort still alive at each age.
survivorship curve
A ______________ _______, or fertility schedule, is an age-specific summary of the reproductive rate in a population.
reproductive table
Ecologists study ____________ _______ in ideal, unlimited environments to reveal how fast populations are capable of growing and the conditions under which rapid growth might actually occur.
population growth
Change in population size during a fixed time interval can be defined with:
change in population size= births+ Immigrants entering population – deaths – emigrants leaving population
deltaN= change in population size, deltat= time interval
B= number of births, D= number of deaths
deltaN/deltat= B–D
The ___ _____ ______ _____ is the number of offspring produced per unit time by and average member of the population.
per capita birth rate
_______ _____________ _______ (_____) occurs when the per capita birth and death rates are equal.
Zero population growth (ZPG)
__________ _____________ ________ occurs when rinst is greater than zero and is constant at each instant in time.
exponential population growth
General equation for exponential growth is:
dN/dt= r(inst) N
Ecologist define the __________ __________, symbolized by K, as the maximum population size that a particular environment can sustain.
carrying capacity
In the _________ ____________ ________ model, the per capita rate of increase approaches zero as the population size nears the carrying capacity.
logistic population growth
Some populations show an ______ ______, in which individuals may have a more difficult tim surviving or reproducing if the population size is too small.
Allee effect
The traits that affect an organism’s schedule of reproduction and survival make up its ______ ________. These traits of an organism are evolutionary outcomes reflected in its development, physiology, and behavior.
life history
Three main variables that life history entails:
1. how often the organism reproduces
2. how many offspring are produced per reproductive episode
3. when reproduction begins
Many organisms undergo a “one-shot” patter of big-bang reproduction, or ____________.
semelparity
In contrast to semelparity is ____________, or repeated reproduction. They tend to produce relatively few but large offspring each time they reproduce, and they provide for an offspring better.
iteroparity
No organism can produce as many offspring as a __________ species and provision them as well as an ________ species. There is a trade-off between reproduction and survival.
semelparous, iteroparous
Selection for traits that are sensitive to population density and are favored at high densities are known as ___-___________, or density-dependent selection.
K-selection
Selection for traits that maximize reproductive success in uncrowded environments is called __-______________, or density-independent selection.
r-selection
A birth rate or death rate that does not change with population is said to be __________ _______________.
density independent
A death rate that increases with population density or birth rate that falls with rising density is said to be ________ ____________, a situation similar to K-selection.
density dependent
Without some type of ________ _________ between population density and the rates of birth and death, a population would never stop growing.
negative feedback
Increasing population density intensifies __________ for nutrients and other resources, reducing reproductive rates.
competition
If the transmission rate of a ________ increases as a population becomes more crowded, then the disease’s impact is density dependent.
disease
__________ can be an important cause of density-dependent mortality if a predator captures more food as the population density of the prey increases
Predation
___________ can limit population density when space becomes the resource for which individuals compete.
Territoriality
_______ _____________ factors can regulate population size.
Intrinsic physiological
Such population fluctuations from year to year or place to place, called ________ __________, are influenced by many factors and in turn effect other species.
population dynamics
While many populations fluctuate at unpredictable intervals, others undergo regular _____-_____-______ _______.
boom-and-bust cycles
When _______ becomes scarce, __________ often turn on one another.
prey, predators
Immigration and emigration are particularly important when a number of local populations are linked, forming a ___________________. Local populations in a _____________ can be thought of as occupying discrete patches of suitable habitat in a sea of otherwise unsuitable habitat.
metapopulation
The movement from high birth and death rate toward low birth and death rates, which tends to accompany industrialization and improved living conditions, is called the ____________ _______________.
demographic transition
Another important demographic variable in present and future growth trends is a country’s ___ _______, the relative number of individuals of each age in a population.
age structure
_____ ____________, the number of infant deaths per 1,000 live births
infant mortality
________ _________ ____ _________, the predicted average length of life at birth, vary widely in different countries.
life expectancy at birth
The ________ ________ concept summarizes the aggregate land and water area required by each person, city, or nation to produce all the resourced it consumes and to absorb all the waste it generates.
ecological footprint