Biology Chapter 53 Population Ecology
Cohort
A group of individuals of the same age from birth until all of the individuals are dead
Survivorship curve
A plot of the proportion or numbers in a cohort still alive at each age
May change as environmental conditions change
A population's carrying capacity ___
Population growth is zero when N equals K
According to the logistic growth equation
Life-tables
Age-specific summaries of the survival pattern of a population
Uniform dispersion
Also referred to as evenly spaced, may result from direct interactions between individuals in the population
The ecological footprint of the United States is large because per capita resource use is high
Analyzing ecological footprints reveals that ____
10 MendAliens per hectare
Assume there are 200 MendAliens living on an island in my back yard. If my island has an area of 20 hectares, what is the population density of MendAliens in terms of MendAliens per hectare?
7 billion
Based on current growth rates, Earth's humans population in 2015 will be closest to ___
Semelparity
Big-bang or "one-shot" reproduction
Mechanism of density-dependent regulation
Competition for resources, disease, predation, territoriality, intrinsic factors, and toxic wastes
there is insufficient information to answer this question
Currently, how large is the worldwide population of humans relative to Earth's carrying capacity for humans?
has a constant, instantaneous per capita growth rate
During exponential growth, a population always ___
Reproductive table
Fertility schedule, is an age-specific summary of the reproductive rates in a population
Population dynamics
Fluctuations from year to year or place to place influenced by many factors and affect other species
The population growth rate decreased.
In 1970, the average age of childbearing was 28, and the average number of offspring per woman was 3 in a certain country. In 1980, the average age of childbearing was still 28, but the average number of offspring per woman was 2 in that country. If the death rate in the country remained constant during those years, how did the population growth rate change from 1970 to 1980? In 1970, the average age of childbearing was 28, and the average number of offspring per woman was 3 in a certain country. In 1980, the average age of childbearing was still 28, but the average number of offspring per woman was 2 in that country. If the death rate in the country remained constant during those years, how did the population growth rate change from 1970 to 1980?
per capita population growth rate
In the models that describe population growth, r stands for _____.
clumped
In wild populations, individuals most often show a _____ pattern of dispersion.
Population
Is a group of individuals of a single species living in the same general area
Density
Is the number of individuals per unit area or volume
Dispersion
Is the pattern of spacing among individuals within the boundaries of the population
Demography
Is the study of the vital statistics of populations and how they change over time
Density-dependent selection
K-selection, for traits that are sensitive to population density and are favored at high densities
Exponential population growth
Occurs when r-inst is greater than zero and is constant at each instant in time
Zero-population growth
Occurs when the per capita birth and death rates are equal
adults
Oyster populations are primarily, if not exclusively, composed of _____.
Determine the birth rate and death rate of each group in a population
Population ecologists follow the fate of same-age cohorts to ___
Iteroparity
Repeated reproduction
Predation is the dominant factor affecting prey population cycling.
Scientific study of the population cycles of the snowshoe hate and its predator, the lynx, has revealed that
Carrying capacity
Symbolized by K, the maximum population size that a particular environment can sustain
It is not possible to compare the population growth rates of countries A and B.
The average age of childbearing in country A is 26, whereas the average age in country B is 30. In each country, the average number of offspring per woman is 3. Which of the following statements about the population growth rate in each country must be true?
Territoriality
The defense of a bounded physical space against encroachment by other individuals
Immigration
The influx of new individuals from other areas
sharks
The mark-recapture method would be best for sampling a population of _____.
Clumped
The most common patter of dispersion is _____ in which individuals are aggregated in patches
Demographic transition
The movement from high birth rate and death rate toward low birth and death rates, which tends to accompany industrialization and improved living conditions is called the
Emigration
The movement of individuals out of a population and into other locations
carrying capacity
The number of individuals that a particular habitat can support with no degradation of that habitat is called _____.
The members of the population are competing for access to a resource
The observation that members of a population are uniformly distributed suggests that
Logistic population growth
The per capita rate of increase approaches zero as the population size nears the carrying capacity
Age structure
The relative number of individuals of each age in the population
the size of the area in which they live
To determine the density of a rabbit population, you would need to know the number of rabbits and _____.
Life history
Traits of an organism are evolutionary outcomes reflected in its development, physiology, and behavior
True
True or false? Factors that determine the per capita rate of increase of a population include the age of breeding and the number of offspring produced each year.
True
True or false? The growth rate of a certain population increases very quickly for a time and then levels off to zero. The most likely reason that the growth rate leveled off to zero is that the environment reached its carrying capacity.
Young populations with few individuals.
Under which of the following conditions would a population most likely experience exponential growth?
Random dispersion
Unpredictable spacing, the position of each individual in a population is independent of their individuals
changes in population through time
What are population dynamics?
Maximum number of individuals in a population.
Which factor does not affect a habitat's carrying capacity?
offspring with good chances of survival
Which of the following is characteristic of K-selected populations?
flooding
Which of the following is regarded as a density-independent factor in the growth of natural populations?
If N is greater than K, the population will shrink.
Which of the following statements about a population experiencing logistic growth is true?
Predictions of a population's future take into account such factors as increasing survivorship and fecundity levels that remain the same.
Which of the following statements about age pyramids is true?
Life history is r-selected
Which of the following statements about human population in industrialized countries is correct?
elephants
Which of these organisms has a survivorship curve similar to that of humans?
grasses
Which of these organisms has a survivorship curve similar to that of oysters?
robins
Which of these species typically has a mortality rate that remains fairly constant over an individual's life span?
the advent of agriculture
Which of these was the first of the major events that stimulated an increase in the size of the human population?
the industrial revolution
Which of these was the second of the major events that stimulated an increase in the size of the human population?
the discovery of vaccines and the discovery of antibiotics
Which of these was the third of the major events that stimulated an increase in the size of the human population?
Iteroparous; K-selected
Which pair of terms most accurately describes life history traits for a stable population of wolves?
births and immigration
Which processes increase a population's size?
585
You are doing a mark-recapture experiment to determine the population size of the MendAliens living on an island in my back yard. Initially, you catch and mark 130 MendAliens, which you then release. Next, you capture 90 MendAliens, of which 20 are marked. What is your estimate of the population size of MendAliens living on the island in my back yard?
Density-independent selection
r-selection, for traits that maximize reproductive success in uncrowded environments