POP: Overview 📖

Populations

Introduction

Studying populations is important to environmental science because populations are the basic units of ecological systems, and they interact with each other and with their environment in complex ways.

By understanding how populations change over time and space, environmental scientists can better predict the effects of human activities and natural disturbances on biodiversity, ecosystem services, and human well-being.

 

Learning Objectives

In this module, you will learn how to....

  • Identify... 
    • differences between generalist and specialist species.
    • differences between K- and r-selected species.
  • Explain...
    • survivorship curves.
    • how resource availability affects population growth.
    • age structure diagrams.
    • factors that affect total fertility rate in human populations.
    • how human populations experience growth and decline.
  • Define the demographic transition.
  • Describe...
    • carrying capacity.
    • the impact of carrying capacity on ecosystems.

 

Module Lessons Preview

In this module, each lesson will focus on teaching you the following topics:

Generalists and Specialists (2-4 mins): Provides insights into species' ecological strategies, adaptability to environmental conditions, and their respective life history traits

K- vs r-selected Species (6-8 mins): Provides insights into species' ecological strategies, adaptability to environmental conditions, and their respective life history traits

Survivorship Curves (2-4 mins): Provides insights into species' ecological strategies, adaptability to environmental conditions, and their respective life history traits, shaping our comprehension of biodiversity dynamics and ecosystem resilience.

Carrying Capacity (7-9 mins): Carrying capacity defines the maximum sustainable population size a given environment can support, influencing species dynamics, resource utilization, and overall ecological balance.

Population Growth (4-6 mins): Population growth influences species interactions, biodiversity, and the overall sustainability of ecological processes.

Age-Structure Diagrams (8-10 mins): Age-structure diagrams provide insights into demographic trends, reproductive patterns, and potential impacts on resource utilization and biodiversity.

Total Fertility Rate (6-8 mins): Total fertility rate increases our understanding of population growth rates.

Population Growth Rate Calculations (10-12 mins): Learn how to calculate population growth rate for different populations.

Human Population Dynamics (33-35 mins): Human population dynamics influence resource consumption, habitat modification, and overall environmental impact, shaping the sustainability and health of interconnected natural systems.

The Demographic Transition (9-11 mins): The demographic transition reflects shifts in human population growth patterns, influencing resource utilization, environmental impact, and the potential for sustainable practices.

 

AP Classroom Connection

This module aligns with Unit 3 in AP Classroom. You can view AP Daily videos, progress checks, and topic questions in AP Classroom. Topic Alignment:

          • Population Ecology: 3.1 - 3.5
          • Human Population Dynamics: 3.6 - 3.9

This module is 10-15% of the AP Environmental Science Exam.

 

Textbook Alignment

This module aligns to the following modules/chapters in your AP Environmental Science textbook:

📚 Generalists and Specialists (Topic 3.1): Ch.5, Module 17

📚 K- vs r-selected Species (Topic 3.2): Ch. 6, Module 19

📚 Survivorship Curves (Topic 3.3): Ch. 6, Module 19

📚 Carrying Capacity (Topic 3.4): Ch. 1, Module 2; Ch. 6, Module 19; Ch. 7, Module 22

📚 Population Growth and Resource Availability (Topic 3.5): Ch. 1, Module 2; Ch. 6, Module 18-19; Ch. 7, Module 23

📚 Age-Structure Diagrams (Topic 3.6): Ch. 7, Module 22-23 

📚 Total Fertility Rate (Topic 3.7): Ch. 7, Module 22; Ch. 11, Module 31

📚 Human Population Dynamics (Topic 3.8): Ch. 7, Module 22-23; Ch. 11, Module 31

📚 The Demographic Transition (Topic 3.9): Ch. 7, Module 23

These modules/chapters cover content found in this module and offer practice videos, questions, and flash cards.

 Key Terms (click to reveal)

🖨 Click here to download a PDF of the Populations Key Terms Links to an external site.

            • Age-structure diagrams: Graphical representations of a population's age distribution, illustrating the proportion of individuals in various age groups.
            • Biotic potential: The maximum reproductive capacity of a population under optimal environmental conditions, often influenced by factors such as birth rate, death rate, and reproductive age.
            • Carrying capacity (K): The maximum population size that a particular environment can sustain over the long term, given the available resources.
            • Clumped dispersal: The spatial distribution pattern where individuals are clustered together, often influenced by resource availability or social structures.
            • Cohort: A group of individuals sharing a common characteristic, usually their birth year, used in demographic studies to track and analyze population dynamics.
            • Crude birth rate: The number of live births in a population per 1,000 individuals per year, without considering age or sex differences.
            • Crude death rate: The number of deaths in a population per 1,000 individuals per year, without accounting for age or sex variations.
            • Cyclic population growth: Fluctuations in population size occurring in regular, repetitive patterns over time.
            • Demographics: The statistical study of populations, focusing on characteristics such as age, gender, density, migration, birth rates, and death rates.
            • Demographic transition: The process of a society transitioning from high birth and death rates to low birth and death rates, often accompanied by economic and social development.
            • Demography: The scientific study of human populations and their characteristics.
            • Density-dependent impacts: Environmental factors whose effects on a population vary with the population's density, such as competition for resources and disease.
            • Density-independent impacts: Environmental factors that affect a population regardless of its density, like natural disasters or climate events.
            • Developed country: A nation characterized by high levels of industrialization, technological advancement, and a high standard of living.
            • Developing country: A nation with lower levels of industrialization, technological development, and a lower standard of living compared to developed countries.
            • Doubling time: The time it takes for a population to double in size, often influenced by its growth rate.
            • Emigration: The movement of individuals out of a population or geographical area.
            • Environmental resistance: Factors that limit a population's growth, including biotic and abiotic factors such as predation, competition, and resource availability.
            • Exponential growth: Population growth that occurs when the growth rate is proportional to the population size, leading to a constant percentage increase over time.
            • Fertility: The ability of a population to produce offspring, often measured by birth rates.
            • Generalist species: Species with a broad ecological niche, capable of thriving in a variety of environmental conditions.
            • Immigration: The influx of individuals into a population or geographical area.
            • Irregular growth: Population growth characterized by unpredictable fluctuations and irregular patterns.
            • J-curve: A graphical representation of exponential population growth, forming a curve that resembles the letter "J."
            • K-strategists: Species that invest heavily in fewer offspring, providing them with more care and increasing their chances of survival in stable environments.
            • Life history: The pattern of an organism's growth, development, and reproduction throughout its life cycle.
            • Linear population growth: Population growth that occurs at a constant rate over time.
            • Logistic population growth: Population growth that levels off as it approaches the carrying capacity, forming an S-shaped curve.
            • Overshoot: When a population exceeds its carrying capacity, leading to a temporary overuse of resources.
            • Population momentum: The continued population growth that occurs after a reduction in the birth rate, due to a youthful age structure.
            • Random dispersal: The distribution pattern where individuals are spread randomly across a landscape, often influenced by chance or wind dispersal.
            • Replacement level fertility: The fertility rate at which each generation can replace itself without increasing or decreasing the population size.
            • Rule of 70: A formula used to estimate the doubling time of a population by dividing 70 by the growth rate.
            • R-strategists: Species that produce many offspring with little parental care, adapted for rapid population growth in unpredictable environments.
            • S-curve: A graphical representation of logistic population growth, forming an S-shaped curve.
            • Specialist species: Species with a narrow ecological niche, adapted to specific environmental conditions.
            • Stable population growth: Population growth that maintains a relatively constant size over time.
            • Survivorship curve: A graph depicting the number of survivors in a population at each age, providing insights into the population's mortality patterns.
            • Total fertility rate: The average number of children a woman is expected to have during her reproductive years.
            • Underdeveloped country: A nation characterized by low levels of industrialization, technological development, and a lower standard of living compared to developed countries.
            • Uniform dispersal: The distribution pattern where individuals are evenly spaced across a landscape, often influenced by territorial behavior or competition for resources.
            • Weedy species: Species with traits that allow them to thrive in disturbed or changing environments, often characterized by rapid growth and reproduction.

 

 

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