Name Date Population Ecology Before You Read Use the “What I Know” column to list the things you know about population biology. Then list the questions you have about population biology in the “What I Want to Find Out” column. Accept all reasonable responses. K W L What I Know What I Want to Find Out What I Learned Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. Science Journal White-tailed deer have become so numerous in some areas of the United States that they are a nuisance. Why do you think these deer populations have grown so large? Accept all reasonable responses. Human land development has removed many deer predators and competitors that would have limited the deer populations naturally. The deer have been able to adapt to the changes in their environments, while many predator and competitor species could not. Population Ecology 31
Name Date Population Ecology Section 4.1 Population Dynamics Main Idea Details Skim Section 1 of the chapter. Write three questions that come to mind from reading the headings and illustration captions. 1. Accept all reasonable responses. 2. 3. Review Vocabulary Use your book or dictionary to define population. population the members of a single species that share the same geographic location at the same time New Vocabulary Compare the terms in the tables by defining them side by side. carrying capacity population density the dispersion pattern of spacing number of organisms per unit of a population within an area Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. density-dependent area factor density-independent factor density-independent factor density-independent any factor in the environment any factor in the environment factor that does not depend on the that depends on the number of number of members in a members in a population per population per unit area unit area dispersion population growth rate speed at which a population grows emigration emigration the number of immigration the number of immigration individuals moving away from a individuals moving into a population population population density carrying capacity the maximum number of individuals in a population growth rate species that an environment can support for the long term Academic Vocabulary Define fluctuate to show its scientific meaning. fluctuate to change from high to low levels or from one thing to another in an unpredictable way 32 Population Ecology
Name Date Section 4.1 Population Dynamics (continued) Main Idea Details Population Identify each pattern of dispersion represented below. Characteristics Random Uniform Clumped I found this information on page . SE, pp. 92–94 RE, pp. 35–36 Random Uniform Clumped Analyze why populations are limited in their spatial distribution. Accept all reasonable responses. A species cannot expand into a new area if it cannot adapt to the biotic and abiotic factors there. Classify each limiting factor below as either density-independent or density-dependent by placing an X in the appropriate column. Density- Density- Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. Factor Independent Dependent Lava flow X Number of predators X Spread of disease X Especially cold winter X Toxic chemical spill into a stream X Another species competing for X the same resources Diverting a river for irrigation X Fungus that attacks elm trees X Analyze how the expansion of housing developments in southern California might limit coyote populations in the area. Accept all reasonable responses. The developments reduce the land available for coyote habitat. They might also reduce the habitat for the coyotes’ prey animals, which would decrease the coyotes’ food supply. Less space and less food would limit the coyote populations. Population Ecology 33
Name Date Section 4.1 Population Dynamics (continued) Main Idea Details Population- Identify four main factors in a population’s growth rate. limiting factors Factors in Population’s Growth Rate I found this information • birthrate or natality • emigration on page . SE, pp. 94–99 • death rate or mortality • immigration RE, pp. 36–39 Compare the general shapes of the curves of population growth graphs. Draw the appropriate graph. Label the lag phase, exponential growth phase, and carrying capacity. Below each graph, describe what the graph shows. Accept all reasonable responses. Exponential Population Logistic Population Growth Growth Graph should resemble the Graph should resemble the J-shape of the figure at the top S-shape of the figure at the of text page 97. The lag phase bottom of text page 97. The and exponential growth phase lag phase, exponential growth should be labeled. phase, and carrying capacity should be labeled. Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. This graph shows how a This graph shows typical population would grow if there population growth. After were no limits placed on it by exponential growth, limiting the environment. The population factors slow the growth until the would grow slowly at first, and population stops growing at its later would grow exponentially. carrying capacity. S UMM ARIZE Analyze whether humans are r-strategists or k-strategists. Explain why. Support your reasoning. Humans are k-strategists. Humans produce few offspring compared to other species. Human parents invest energy, resources, and time in caring for their offspring, increasing the chances that the young will survive to reproductive age. Humans also fit the profile of a k-strategist as a larger organism with a long life span. 34 Population Ecology
Name Date Population Ecology Section 4.2 Human Population Main Idea Details Skim Section 2 of the chapter. Make a list of the ways in which human populations change. Accept all reasonable responses. Review Vocabulary Use your book or dictionary to define carrying capacity. carrying capacity the maximum number of individuals in a species that an environment can support for the long term New Vocabulary Use your book or dictionary to define each term. Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. age structure in a population, the number of males and females in each of three age groups: pre-reproductive stage, reproductive stage, and post-reproductive stage demographic transition a change in a population from high birth and death rates to low birth and death rates demography the study of human population size, density, distribution, movement, and birth and death rates zero population situation in a population in which birthrate equals death rate growth (ZPG) Population Ecology 35
Name Date Section 4.2 Human Population (continued) Main Idea Details Human Summarize two examples of events that could produce each of the Population following effects. Accept all reasonable responses. Growth Effect: decline in world population growth I found this information Events that could produce this effect: worldwide epidemic; on page . SE, pp. 100–101 world war RE, p. 40 Effect: increase in world population growth Events that could produce this effect: new medicine reduces death rate; new farming method yields more food per acre Examine the graph below. Then complete the table that follows. Accept all reasonable responses. Percent Increase in Human Population 2.2 2.0 1.8 Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. 1.6 Percent increase 2003 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 1950 1975 2000 2025 2050 Year Approximate Growth Rate 1950 1975 2000 2025 (estimated) 1.7 1.8 1.3 0.9 What are the main reasons for the expected trend in human population between now and 2050? diseases such as AIDS and voluntary population control 36 Population Ecology
Name Date Section 4.2 Human Population (continued) Main Idea Details Trends in Human Calculate the population growth rate for each fictitious country Population listed in the table below. Growth Births per Deaths per Growth rate I found this information Country 1000 1000 (percent) on page . -1.6 X 25 9 SE, pp. 102–105 Y 14 4 -1.6 RE, pp. 41–42 Z 12 15 -0.3 Compare trends in industrialized nations and developing countries in terms of the following factors. Population growth rate: The population is growing at a faster rate in developing than in developed countries. Resource use by individuals: Individuals in industrialized nations use far more resources than individuals in developing countries. Identify three factors that could keep the human population from Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. reaching its carrying capacity. 1. family planning 2. improvements in technology 3. limiting the amount of resources each person uses S UMM ARIZE Imagine that medical science discovered a cure for all cancers. Analyze how this medical achievement might affect life on Earth. Accept all reasonable responses. The cure would probably decrease the death rate, resulting in rapid human population growth at first. Then other limiting factors would slow the exponential growth. Overcrowding would increase the spread of other diseases and of parasites. The food supply could not support the increased population, leading to starvation. Competition for resources between humans and other species might decimate animal and plant populations. Population Ecology 37
Name Date Tie It Together Create a demographic profile for an imaginary country F URTHER I NQUIRY by describing its population characteristics below. List the sources of your data. Accept all reasonable responses. Name of country: Geographic location: Is it classified as a developing country or as an industrialized nation? Population size: Population density: Description of the population’s spatial distribution across the country’s land area: Birthrate: Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. Death rate: Current population growth rate: Expected population growth rate in the next 10 to 20 years: General age structure: Major factors promoting population growth: Major factors limiting population growth: Data sources used: 38 Population Ecology