...half the test population by the route...
...half the test population by the route...
...half the test population by the route...

...Population Ecology Overview: Turtle...
...others do not? Population ecology is the...
...to their environment. Population ecology explores how...
...abiotic influences on population density, distribution, size,...
...Biological processes influence population density, dispersion, and...
...and demographics. A population is a group...
...Members of a population rely on the...
...begin investigating a population by defining boundaries...
...individuals in any population are density, dispersion,...
...density of a population is the number...
...dispersion of a population is the pattern...
...they usually estimate population numbers. It is...
...individuals in a population. Ecologists use a...
...densities and total population sizes. For example,...
...to estimate the population size in the...
...of counting individuals, population ecologists may estimate...
...an index of population size, such as...
...individuals in the population. The mark-recapture method...
...a second time. Population density results from...
...individuals to a population and processes that...
...Additions to a population occur through birth...
...individuals from a population are death (mortality)...
...out of a population). Immigration and emigration...
...populations. Within a population’s geographic range, local...
...density are important population characteristics, providing insight...
...individuals within a population. Some habitat patches...
...members of a population may maintain patterns...
...individual in a population is independent of...
...individuals in a population, or when key...
...pattern of a population. The best way...
...determining changes in population size. Demographers who...
...rates in a population, constructed by measuring...
...lead to rapid population growth unless conditions...
...exponential model describes population growth in an...
...for growth. Unlimited population increase does not...
...The study of population growth in an...
...Imagine a hypothetical population living in an...
...environment. Change in population size = Births...
...– Emigrants entering population leaving population For...
...entering population leaving population For simplicity, we...
...emigration: Change in population size = Births...
...If N represents population size and t...
...the change in population size and t...
...member of the population. For example, if...
...year in a population of 1,000 individuals,...
...time in a population of any size....
...time in a population of any size...
...year in a population of 1,000 individuals....
...can revise the population growth equation, using...
...bN ? mN Population ecologists are most...
...indicates whether a population is growing (r...
...there is zero population growth (ZPG). Births...
...the change in population size as: N/t...
...calculus to express population growth instantaneously, as...
...rate of increase. Population growth under ideal...
...is called exponential population growth. Under these...
...rate for the population (rinst), called the...
...equation for exponential population growth is dN/dt...
...size of a population that is growing...
...curve when the population size is plotted...
...is constant, the population accumulates more new...
...over time. A population with a high...
...describes how a population grows more slowly...
...limited and, as population density increases, each...
...the maximum stable population size that a...
...rate as the population size nears the...
...In the logistic population growth model, the...
...the maximum sustainable population size (carrying capacity)...
...still available for population growth. By multiplying...
...rate of the population as N increases:...
...the rate of population growth. Population growth...
...of population growth. Population growth is greatest...
...greatest when the population is approximately half...
...capacity. At this population size, there are...
...logistic model of population growth produces a...
...added to the population most rapidly at...
...rapidly at intermediate population sizes, when there...
...a substantial breeding population but also lots...
...resources in the population. The population growth...
...the population. The population growth rate slows...
...Why does the population growth rate slow...
...N approaches K? Population growth slows as...
...effects of increasing population are realized. Populations...
...regardless of the population density, each individual...
...added to the population has the same...
...effect on the population growth rate. Some...
...reproducing if the population is too small....
...season at small population sizes. A plant...
...alone. The logistic population growth model provides...
...rapidly a particular population might increase after...
...traits at different population densities with the...
...logistic model of population growth. Selection for...
...are sensitive to population density is known...
...tends to maximize population size and operates...
...environments in which population densities fluctuate well...
...factors that regulate population growth are density-dependent....
...factors stop a population from growing indefinitely?...
...remain relatively stable? Population regulation is an...
...effects of increased population density on rates...
...other, then a population grows when the...
...not change with population density is density-independent....
...of a local population regardless of density....
...that falls as population density rises is...
...declines as the population density increases, in...
...feedback prevents unlimited population growth. We can...
...negative feedback on population growth, halting population...
...population growth, halting population growth through mechanisms...
...crowded populations, increasing population density may increase...
...Beyond a certain population density, additional birds...
...individuals in a population is an indication...
...territoriality is restricting population growth. Population density...
...restricting population growth. Population density can also...
...crowding in a population, then the disease’s...
...food as the population density of the...
...As a prey population builds up, predators...
...density-dependent regulation of population size. In laboratory...
...as a yeast population increases, yeast accumulate...
...appear to regulate population size. White-footed mice...
...more aggressive as population size increases, even...
...Eventually the mouse population ceases to grow....
...The study of population dynamics focuses on...
...cause variations in population size. Populations of...
...size of this population to change so...
...size of the population. When sheep numbers...
...also cause the population to shrink. Conversely,...
...available and the population grows quickly. A...
...quickly. A long-term population study has found...
...that the moose population on Isle Royale...
...regulating the moose population. Moose from the...
...emigration. The moose population experienced two major...
...in the wolf population from 1975 to...
...populations show cyclic population changes. Small herbivorous...
...striking example of population cycles is the...
...interactions. Snowshoe hare population size may vary...
...activity. If hare population cycles are due...
...to a field population. Researchers conducted such...
...found that hare population densities increased about...
...in the hare population. All of these...
...major factor influencing population changes for predators...
...causes of these population cycles. Immigration and...
...populations: When a population becomes crowded and...
...patches. If one population becomes extinct, the...
...immigrants from another population. The metapopulation concept...
...helps ecologists understand population dynamics and gene...
...53.6 The human population is no longer...
...The concepts of population dynamics can be...
...of the human population. It is unlikely...
...that any other population of large animals...
...sustained so much population growth for so...
...long. The human population increased relatively slowly...
...Since then, human population numbers have doubled...
...three times: Our population doubled to 1...
...billion. The global population is now more...
...people each day. Population ecologists predict a...
...ecologists predict a population of 7.8–10.8 billion...
...Although the global population is still growing,...
...in the global population peaked at 2.2%...
...by 2050. Human population growth has departed...
...fundamental changes in population dynamics due to...
...AIDS, and voluntary population control. Population dynamics...
...voluntary population control. Population dynamics vary widely...
...region. To maintain population stability, a regional...
...a regional human population can exist in...
...two configurations: Zero population growth = High...
...death rates Zero population growth = Low...
...birth rate. The population is already declining...
...European countries. Most population growth is concentrated...
...feature of human population growth is our...
...help to decrease population growth rates and...
...society toward zero population growth. World leaders...
...percentage of the population at each age....
...can predict a population’s growth trends and...
...of the human population vary from 7.8...
...future maximum human population size. Others generalize...
...the existing “maximum” population density and multiply...
...the global human population, the result is...
...per person and population density determines our...
...for the human population. Malnutrition and famine...
...up with global population growth. Perhaps we...
...space. As our population grows, conflict over...
...needs. The human population may eventually be...
...humans, but no population can continue to...
...decide whether zero population growth will be...

...Populations Population growth Definition of...
...growth Definition of population: All the individuals...
...the rate of population growth: Food supply...
...supply Increase in population Limited supply Decrease...
...supply Decrease in population Predation When there...
...an increase in population, disease will spread...
...more rapidly. The population will then decrease...
...three phases 212725210820Time Population LAG LOG STATIONARY...
...limiting factors 00Time Population LAG LOG STATIONARY...
...limiting factors Human population growth Reasons for...
...rapid increase in population size: Reduction of...
...Factors effecting human population growth Birth rate...
...rate ZPG (Zero Population Growth) Emigration (Leaving...
...implications of human population growth Most barriers...
...barriers to human population growth have been...
...have been eliminated. Population of the world...
...now increases rapidly (population explosion). Birth control...
...Increase in human population results in: Less...
...Interpreting graphs Increasing population Stable population Many...
...Increasing population Stable population Many young at...

...tracking how a population of organisms changes...
...It is the population, not its individual,...
...frequencies in a population. For example, the...
...their lifetimes. A. Population Genetics The Origin...
...arise in a population while also accounting...
...the birth of population genetics, which emphasizes...
...characters. Advances in population genetics in the...
...taxonomy, biogeography, and population genetics. The architects...
...evolve. 2. A population’s gene pool is...
...allele frequencies A population is a localized...
...Members of a population are far more...
...of the same population than with members...
...Individuals near the population’s center are, on...
...genes in a population at any one...
...is called the population’s gene pool. It...
...individuals of a population. Each locus is...
...members of a population are homozygous for...
...imagine a wildflower population with two flower...
...in an imaginary population of 500 plants,...
...diploid, in our population of 500 plants...
...pool of this population is 800/1000 =...
...describes a nonevolving population The Hardy-Weinberg theorem...
...of a nonevolving population. This theorem states...
...genotypes in a population’s gene pool will...
...pool of a population. In our imaginary...
...our imaginary wildflower population of 500 plants,...
...flower-color locus, the population’s genetic structure is...
...shuffling of a population’s gene pool over...
...the Hardy-Weinberg theorem, population geneticists use p...
...of the human population that carries the...
...of the U.S. population carries the PKU...
...conditions. Very large population size. In small...
...of our target population can change the...
...met— when a population experiences deviations from...
...change in a population’s allele frequencies The...
...of an evolving population. We can define...
...change in a population’s frequencies of alleles....
...locus in a population while the others...
...frequencies in a population: Genetic drift Natural...
...generally adapts a population to its environment....
...drift at small population sizes often occurs...
...Applied to a population’s gene pool, we...
...size of the population is large (theoretically,...
...of a small population may not be...
...a small wildflower population with a stable...
...in a larger population are drastically reduced...
...pool until the population is large enough...
...when a new population is started by...
...the larger source population. At an extreme,...
...an extreme, a population could be started...
...of the source population. Genetic drift would...
...generation until the population grew large enough...
...individuals in a population have equal ability...
...However, in a population with variable individuals,...
...allele in the population and decrease that...
...genotypes in a population. Gene flow is...
...a nearby wildflower population consisted entirely of...
...into our target population. This would increase...
...in the target population in the next...
...into a single population with a common...
...into a single population with a common...
...pool of a population by substituting the...
...on a large population in a single...
...individuals in a population is a combination...
...variation within a population. Quantitative characters are...
...continuum within a population. For example, plant...
...in our wildflower population includes short and...
...noticeable in a population. The contrasting forms...
...in our wildflower population or the butterflies...
...in a continuum. Population geneticists measure genetic...
...individuals in a population. In fruit flies,...
...of a single population that inhabit different...
...scale, within a population, if the environment...
...in the HIV population at every site...
...alleles from the population gene pool. The...
...persist in a population through their propagation...
...diversity in a population via natural selection....
...common in the population. The relationships between...
...in the parasite population shifts. These shifts...
...food. In a population of moths, some...
...of other individuals. Population geneticists use a...
...In a hypothetical population of wildflowers, RR...
...selection adapts a population to its environment...
...trait in a population, leading to: Directional...
...members of a population migrate to a...
...increase in the population. Diversifying selection occurs...
...output. If a population consisted of half...
...would generate a population of eight females...

...species is a population or group of...
...can fragment a population into two or...
...may divide one population into isolated groups....
...from the parent population. For example, mainland...
...increases when a population is both small...
...A small, isolated population is more likely...
...carried a small population of mainland finches...
...several generations, the population raised on starch...
...from the original population, because of abnormal...
...subset of the population without geographic separation...
...from the parent population. In plants, the...
...subset of the population is reproductively isolated...
...from their parent population. After establishing themselves...
...generations in a population’s allele frequencies, mainly...
...occurs when a population’s genetic divergence from...
...from its ancestral population results in reproductive...

...2008 the world population had reached approximately...
...highest rate of population change in the...

...predict changes in population sizes). (Modules 12.4–12.6)...
...the seasons? 2. Population ecology a. Population...
...Population ecology a. Population is a group...
...same time. b. Population ecology is concerned...
...factors that affect population size, growth, and...
...into how a population changes over time....
...over time. A. Population 1. A population...
...Population 1. A population consists of members...
...environmental factors. 4. Population ecology studies changes...
...over time. B. Population density and dispersion...
...size of a population may be counted...
...of a given population will live to...
...predict changes in population size. • CORE...
...• CORE IDEA: Population growth can be...
...affect the maximum population size in an...
...occurs when the population size of each...
...generation. a. A population may double every...
...The rate of population growth continuously rises...
...continuously rises with population size. 3. It...
...size of a population. 2. Carrying capacity...
...is the maximum population size that can...
...size of a population grows rapidly to...
...capacity and then population growth slows. a....
...carrying capacity, the population size does not...
...depending on the population density. ii. Most...
...iii. As the population grows, competition intensifies,...
...not relate to population size. ii. Abiotic...
...same regardless of population size. iv. Many...
...frost. 12.6 Human population growth has been...
...IDEA: The human population has exhibited exponential...
...structure of a population can give insight...
...A. The human population growth curve 1....
...was high. a. Population growth was slow....
...resulted in a population explosion during the...
...4. The current population is 7.2 billion....
...1985—Pyramid shape of population growing is due...
...will be increasing population size. 3. United...
...percent of the population being over 65...
...harmful for one population but helpful for...
...they affect each population involved. Type of...
...Effect on interaction population 1 population 2...
...interaction population 1 population 2 Example Different...
...50 years, the population hugely increased. c....
...helps keep the population in check. b....
...a constant, low population. 4. Integrated pest...
...genetic (within a population), species, and ecosystem-wide....
...genes within a population. 2. Genes are...
...variation makes a population less able to...
...Endangered species—rapidly declining population due to human...
...decreasing Antarctic penguin population. 4. Fires a....
...Community Organism Consumer Population 12.3 Ecosystems include...
...dispersion. Age structure Population density Survivorship curve...
...curve Dispersion pattern Population ecology Population Survivorship...
...pattern Population ecology Population Survivorship 12.5 Growth...
...predict changes in population size. Carrying capacity...
...factor 12.6 Human population growth has been...
...thing. 12.6 Human population growth has been...
...Lake Erie > Population of bald eagles...
...predict changes in population size. ? Tell...

...Overproduction i. Every population has the potential...
...Individuals in a population vary in many...
...and reproduce, a population will change over...
...in action 1. Population with variation a....
...Members of this population of bacteria differ...
...5. Change in population over time a....
...bacteria within the population increases, rendering the...
...evolve, but a population of organisms may....
...selection within a population will result in...
...traits in a population over time. B....
...genes in the population). Microevolution is a...
...Populations 1. A population is a group...
...changes in a population over time. 104...
...of the same population or not. a....
...and the same population because they can...
...from the same population. The squirrels cannot...
...and the same population because they can...
...genes in a population at any one...
...member of a population has a unique...
...pool of a population changes over time....
...changes in a population’s gene pool. 2....
...migration (into a population) or emigration (out...
...(out of a population) of individuals. b....
...c. The human population has become more...
...a. Sometimes, a population is drastically reduced...
...the reduction in population size. i. Cheetahs...
...leaves the main population to found a...
...found a new population. d. By chance,...
...effect, the new population will have less...
...than the original population. 4. Sexual selection...
...makeup of a population. B. Speciation 1....
...i. An ancestral population changes gradually over...
...i. An ancestral population splits into two...
...ii. Each new population gradually evolves into...
...species is a population that is capable...
...separates a single population into two or...
...separation of a population by physical barriers....
...Gene pool Microevolution Population 7.7 Evolution proceeds...
...pool of a population. An individual is...
...are the same population, but the squirrels...
...member of that population. An individual’s genes...
...in a nonmajors population. ? Most people...
...the most fit population for that time...
...selection in that population? ? There are...
...bird groups one population, but the two...

...most recent world population doubling, to a...
...to a total population of about 6...
...this rate of population will continue for...
...would the world’s population be two centuries...
...that our present population growth will continue...
...most recent world population doubling has occurred...
...1985–1990, annual U.S. population growth was 0.8%...
...double? 14. World population is now about...
...when would world population be 12 billion?...

...most recent world population doubling, to a...
...to a total population of about 6...
...this rate of population will continue for...
...would the world’s population be two centuries...
...that our present population growth will continue...
...most recent world population doubling has occurred...
...1985–1990, annual U.S. population growth was 0.8%...
...double? 14. World population is now about...
...when would world population be 12 billion?...