NSCI 111 People and the Earth's Ecosystem Module PDF

Module in NSCI 111: People and the Earth’s Ecosystem  Module in NSCI 111: People and the Earth’s Ecosystem Dr. Grace A. Manajero – Main Campus Team Leader Members: Prof. Mae B. Angeles – Pototan Campus Prof. Marian M. Banquillo – Jani...

Module in NSCI 111: People and the Earth’s Ecosystem  Module in NSCI 111: People and the Earth’s Ecosystem Dr. Grace A. Manajero – Main Campus Team Leader Members: Prof. Mae B. Angeles – Pototan Campus Prof. Marian M. Banquillo – Janiuay Campus Dr. Anita Estela M. Monroy – Main Campus Prof. Agustin H. Verzo – Pototan Campus i  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) First Edition: August 13, 2020 The Module Writers DR. GRACE A. MANAJERO Associate Professor 5 Faculty, West Visayas State University, Main Campus PH. D. in Science Education- Physical Science MAT in in Physical Science Graduate Diploma in Curriculum Administration-Science BS in Physics for Teachers Module Unit 1- The Human Population (Team Leader) PROF. MAE B. ANGELES Instructor 1 Faculty, West Visayas State University, Pototan Campus Ph. D. in Science Education – Biology (On-going) MA Ed in Biological Sciences BSEd in Biology Module Unit 2 – Ecosystem (Member) DR. ANITA ESTELA M. MONROY Professor 3 Faculty, West Visayas State University, Main Campus Ph. D. in Science Education – Biology MA Ed in Physical Science BS in Chemical Engineering Module Unit 2 – Ecocystem (Member) PROF. MARIAN M. BANQUILLO Instructor 1 Faculty, West Visayas State University, Janiuay Campus Ph. D. Educational Management (On-going) MAT in General Science BSEd in General Science Module Unit 3 – Anthropogenic Impact (Member) PROF. AGUSTIN H. VERZO Assistant Professor 3 Faculty, West Visayas State University, Pototan Campus Ed. D. in Science Education (On-going) MA Ed. Physics BSEd Physics Module Unit 4 – Environmental Sustainability (Member) ii Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) NOTES TO STUDENTS This Module is part of the series of Self-Directed Module for Independent Learning spearheaded by the Office of the Director of Instruction and the Center for Teaching Excellence, West Visayas State University. This is intended for the course NSCI 111- People and the Earth’s Ecosystem. People and the Earth’s Ecosystem is a General Education Course which deals with the impact of human activities on the environment and its consequences of environmental modification on human activity (CMO No. 20 s. 2013). It is the portion of the curriculum common to all independent students regardless of their major. The activities included in this module are presented in the manner that may promote independent and self-directed learning of the subject. There are 17 lessons in this module. They are listed as follows: Unit # Lesson # Title Week # Unit I 1 Human Population Growth 1 2 Human Population Dynamics 2 3 Population Pyramid: The shape of the 3 population Unit II 4 Ecosystem 4 5 Characteristics of Life 5 6 What keeps us and other organism alive? 6 7 What are the major components of an 7 ecosystem? 8 What happens to an energy in an 8 ecosystem? 9 What happens to matter in an 9 ecosystem? MID-TERM EXAM November 3- 6, 2020 Unit III 10 The Anthropocene 10 11 Ecological Footprints 11 12 Anthropogenic impact: Pollution 12 1 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) 13 Anthropogenic impact: Land degradation 13 14 Anthropogenic impact: Global warming 14 15 Anthropogenic impact: Biodiversity loss 15 Unit IV 16 Environmentally Sustainable Society 16 17 Philippine Environmental Laws 17 FINAL EXAM January 25- 28, 2021 The learning outcomes for NSCI 111 – People and the Earth’s Ecosystem, are specified as follows: At the end of the course, the students must have: 1. discovered ways on how humans and human population shaped the environment. 2. explored the scientific and political controversies of environmental issues and solutions. 3. learned how to critically analyze environmental issues to intellectually engage with the community. 4. developed their collaborative, creative thinking, critical thinking, and communication skills. 5. demonstrated awareness on human impacts to the environment and initiated programs and activities concerning solutions to the environmental issues/problems. May you please be familiarized with the parts of this module and the icons to guide you through the instructional material. You are right now reading the Notes to the Students. This will be followed by the Table of Contents. The Units mentioned earlier will be introduced and the lessons within each unit will be presented to you. Feedbacks, rubrics, or answers to questions on tests and activities are usually given immediately after it. The module will be presented in this sequence. Pre-test. This is a test to check your knowledge about the subject. 2 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Pre-Assessment. This will test your prior knowledge about the topic being discussed in each lesson. Review of the Lesson. Lessons previously learned will be reviewed and is related to the new lesson. Motivation. In here, you will do an activity that may perk-up your mind about the new lesson. New Lesson. This is where the lesson is presented. Each of the lessons is presented in a variety of strategies that may entail independence in learning of the topics. Summary. It sums up important concepts that you should have learned in each lesson. Reflection. In this part, you will be asked to answer questions that may reveal your personal note, comment, remarks about the lesson. Post-Assessment. This test will let you know how much of the lessons you have understood. You may also be able to realize the gaps and misconceptions in your understanding of the lesson. Feedback. Answers to tests and guide questions for analysis are shown here, usually written immediately after it. Rubrics on how the activity or open ended questions may be rated will appear in this part of the module. References. This will show you the list of resources and links from where the contents of lessons were based from, usually given in each lesson. These may take the form of books, internet sites, videos, photographs, and animations. 3 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Unit Test/Post Test. This is a test to determine your understanding of the topics presented in the entire unit. Table of Contents Page Title Page i About the Writers ii Notes to Students……………………………………………………………………………….. 1 Table of Contents 4 Pre-Test……………………………………………………………………………………………. 5 Unit 1: The Human Population……………………………………………………………… 12 Lesson 1: Human Population Growth……………………………………………. 13 Lesson 2: Human Population Dynamics…………………………………………. 26 Lesson 3: Population Pyramid: The Shape of the Society’s Population 40 Unit 2: Ecosystems: What are they and how do they work?....................... 51 Lesson 4: Ecosystem…………………………………………………………………… 53 Lesson 5: Characteristics of Life…………………………………………………… 70 Lesson 6: What keeps Us and other Organisms Alive?....................... 86 Lesson 7: What are the Major Components of an Ecosystem?............ 96 Lesson 8: What happens to an Energy in an Ecosystem?................... 110 Lesson 9: What happens to Matter in an Ecosystem?........................ 125 Unit 3: Anthropogenic Impact to the Environment………………………………….. 140 Lesson 10: The Anthropocene……………………………………………………… 141 Lesson 11: Ecological Footprints…………………………………………………… 148 Lesson 12: Anthropogenic Impact: Pollution………………………………….. 155 Lesson 13: Anthropogenic Impact: Land Degradation…………………….. 178 Lesson 14: Anthropogenic Impact: Global Warming……………………….. 192 Lesson 15: Anthropogenic Impact: Biodiversity Loss………………………. 202 Unit 4: Environmental Sustainability……………………………………………………… 218 Lesson 16: Environmentally Sustainable Society…………………………….. 219 Lesson 17: Philippine Environmental Laws…………………………………….. 231 4 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Pre -test Write the letter of your answer in the space provide before each item. _____ 1. The number of people living in a particular area, from a village to the world as a whole. a. human population growth c. human population b. human birth rates d. human exponential growth _____ 2. What does a J-shaped human population graph indicate? a. stability c. levelling off b. exponential growth d. decline _____ 3. When did human begin to migrate? a. 200,000 years ago c. starting 1AD b. 100,000 years ago d. starting 2015 _____ 4. In which part of Africa did the first modern human evolved? a. Sudan c. Nigeria b. Ethiopia d. Kenya _____ 5. Which of the following is not included in the study of human population? a. deaths c. migration b. births d. energy flow _____ 6. Which tells us of the density of the population? a. 337 people c. 337% b. 337 km2 d. 337 people/km2 _____ 7. The choices below are factors that may cause the uneven distribution of people on Earth, except for one. Which one is it? a. climate c. social b. age d. economic _____ 8. It displays a population that has low birthrates but high death rates, and large proportion of the population has a better access to education and health care. a. expansive c. constrictive b. stationary d. either expansive or constrictive 5 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) _____ 9. The population pyramid is also known as the a. population explosion c. age-sex population pyramid b. exponential population growth d. age-sex structure _____ 10. Which of the following situations may cause a land area to be densely populated? a. Job opportunities are present. b. Availability of rich resources. c. Dry climatic conditions d. Climatic conditions conducive for domestication of animals. ______ 11. A Biome a. is a way to describe a large group of similar ecosystems. b. includes all populations if living things. c. is the place where an organism lives within an ecosystem. d. is the complete role or function of an organism in its ecosystem. _______ 12. The rainforests in South America support many ecosystems. These ecosystems are healthy. How does the diversity in the rainforests help determine the health of ecosystems? a. When diversity is high, there are more resources available. b. Resources in the environment last longer when the diversity is low. c. Less diverse ecosystems have less competition among the residents. d. Areas with high diversity have increased competition among the residents. _______ 13. How could we know for a backyard ecosystem to have low diversity? a. The number of insect species is very low. b. There are more insect species present in the environment. c. The plant species outnumber the insect and other animal species. d. There are only a few different species of plants, animals, and insects. 6 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) _______ 14. The branch of biology dealing with interactions among organisms and between organisms and their environment is called a. economy b. modeling c. recycling d. ecology ______ 15. Which of the following descriptions about the organization of an ecosystem is correct? a. Communities make up species, which make up populations. b. Populations make up species, which make up communities. c. Species make up communities, which make up populations. d. Species make up populations, which make up communities. ______ 16. Which of the following is NOT a characteristic of all living things? a. growth and development c. response to the environment b. ability to move d. ability to reproduce ______ 17. Which of the following characteristics of living things best explains why humans sweat when they get hot? a. growth and development b. maintaining a stable internal environment c. using energy d. ability to reproduce ______ 18. Which of the following characteristics of living things best explains why your legs and arms get longer and stronger as you get older? a. Living things respond to their environment. b. Living things maintain internal balance. c. Living things are made up of units called cells. d. Living things grow and develop. ______ 19. In all of our cells there is a blueprint of life called DNA. Which characteristic does this fact best describe? a. Living things respond to their environment. b. Living things maintain internal balance. c. Living things are based on a universal genetic code. d. Living things grow and develop. ______ 20. Consist of the parts of the atmosphere, hydrosphere, and geosphere where life exist. a. Geosphere c. Hydrosphere b. Atmosphere d. Biosphere 7 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) ______ 21. Before a big soccer game Charlie always eats and metabolizes a big dinner. Which characteristic of life does this fact best describe? a. Living things respond to their environment. b. Living things grow and develop. c. Living things reproduce. d. Living things use energy. ______ 22. One percent (1%) of the air, which absorb and release energy that warms the lower atmosphere. a. Stratosphere c. Troposphere b. Greenhouse Gases d. Ionosphere ______ 23. This allows the planet to hold onto the atmosphere and enable the movement and cycling of chemicals through the systems. a. Gases b. Trees c. Gravity d. Nutrient ______ 24. Consist of all of the water on or near the Earth’s surface. a. Ecosystem b. Rocks c. Geosphere d. Hydrosphere ______ 25. This governs the nutrient cycling process. a. Law of Conservation of matter c. Law of Energy Conservation b. Law of thermodynamics d. Laws of Motion _____ 26. An animal that eats both plants and animals is called a a. Herbivore b. Carnivore c. Univore d. Onmivore ______ 27. The Sun is a a. Tertiary Producer of energy c. producer of water b. Secondary source of energy d. Primary producer of energy ______ 28. The green color of plants is produced from organelles called a. cell membranes b. cytoplasm c. chloroplasts d. vacuoles ______ 29. Matter flows through the trophic levels of food webs when carbon dioxide in the atmosphere is converted into a chemical compound through which process? a. Decomposition c. Cellular Respiration b. Photosynthesis d. Nitrogen Fixation ______ 30. Which one of these organisms would be classified as a tertiary consumer? a. mouse b. frog c. hawk d. snake 8 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) ______ 31. What is the original source of almost all the energy in most ecosystems? a. carbohydrates b. sunlight c. water d. carbon Refer to the drawing below for number 32. ______ 32. The algae at the beginning of the food chain are a. consumers b. decomposers c. producers d. heterotrophs ______ 33. An organism that uses energy to produce its own food supply from inorganic compounds are called a(an) a. heterotroph b. consumer c. detritivore d. autotroph. ______ 34. The total amount of living tissue within a given trophic level is called the a. organic mass b. trophic mass c. energy mass d. biomass. ______ 35. An ecological model of the relationships that form a network of complex interactions among organisms in a community from producers to decomposers? a. food web b. an ecosystem c. food chain d. a population _______ 36. It is the term used to describe those species whose population reach the critical level. a. extinct b. endangered c. vulnerable d. threatened _______ 37. Why is genetic diversity important? a. It gives us more choice of food. b. It helps nature to adapt to changing climates. c. It is used for medical research to develop drugs. d. All of the above _______ 38. The following are the causes of biodiversity loss except a. wildlife farms b. poaching c. invasive species d. hunting _______ 39. This period is characterized by the major impact of human activities to the earth’s ecosystem and climate. a. Holocene b. Cenozoic c. Anthropocene d. Mesozoic 9 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) _______ 40. Identify the concept of land described by this situation. Ownership of the West Philippine Sea is an issue between Philippines, China and other neighboring countries. a. property b. economic good c. territory d. natural resource _______ 41. This soil layer is ideal for agriculture since it is rich in nutrients. a. parent material c. subsoil b. top soil d. eluvial _______ 42. A condition where soil becomes oversaturated with water that the roots of the plants are submerge that they will eventually die. a. waterlogging b. salinization c. leaching d. irrigation _______ 43. The most serious water pollutants in terms of human health. a. inorganic chemicals c. radioactive materials b. infectious agents d. organic chemicals _______ 44. Which does not belong to the group? a. aluminum cans b. bottles c. food scraps d. scrap iron _______ 45. Who are likely to be at risk by climate change? a. island countries c. children and the elderly b. outdoor workers d. all of the above _______ 46. Which greenhouse gas is produce by livestock production and other agricultural activities? a. Carbon dioxide c. CFCs b. Methane d. Nitrous oxide _______ 47. The chemical reaction of this pollutant with other substances causes acid rain. a. SO2 b. CO C. NO3 d. VOCs ________ 48. Which of your activity will increase your carbon footprint? a. walking c. buying local products b. drying your clothes under the sun d. organic farming ________ 49. How can you help reduce CO2 emission? a. plant more trees c. burning of garbage b. carpooling d. a and b only ________ 50. Which does not belong to the group? a. Hepatitis b. asthma c. cholera d. diabetes 10 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) _____ 51. Human impact on the environment is often more dramatic than the impact of most other living things because humans have greater a. need for water c. ability to adapt to change b. need for food d. Ability to alter the environment _____ 52. What is a sustainable development? a. The development that meets the needs of the present without compromising the ability of future generations to meet their own needs. b. To conserve natural resources and to develop alternate sources of power while reducing pollution and harm to the environment. c. It is the practice of developing land and construction projects in a manner that reduces their impact on the environment by allowing them to create energy efficient of self-sufficiency. d. All of the above _____ 53. This refers to a forest reservation essentially of natural wilderness character which has been withdrawn from settlement, occupancy or any form of exploitation except in conformity with (an) approved management plan and set aside as such to conserve the area or preserved the scenery, the natural and historic objects, the wild animals and plants therein and to provide enjoyment of these features in such areas. a. National Park c. Natural Biotic Park b. Wildlife Biotic Area d. Natural Park _____ 54. Household and commercial waste should be classified into wet and dry categories before they are collected by the garbage collectors are mandated by this law. a. RA 9003 b. RA 9275 c. RA 8749 d. RA 9147 _____ 55. This law bans almost all forms of garbage incineration and imposes higher emission standards on oil products to lower the amount of pollution they generate. a. RA 9003 b. RA 9275 c. RA 8749 d. RA 9147 11 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Unit 1: The Human Population Introduction Humans are remarkable creatures, in fact, very clever, resilient, and adaptable – perhaps a little too adaptable (Dovers & Butler, 2015). Humans started from small pockets coming from Africa, then evolved to finally colonize almost every corner of the planet Earth. They grew in number --- in 2015, the world population is more than 7.3 billion. Modern humans need to be fed, clothe, nurtured, and educated. Thus, human population and its growth pose a great deal of impact to the environment. This lesson will lead us to run-through the timeline of population growth, identify the causes of human population growth, as well as gather, describe, and interpret human population demography and human population dynamics data using tables, graphs, and charts. Unit Learning Outcomes At the end of the unit, the students must have: 1. traced the human population through time. 2. identified possible causes of human population growth and described the possible effects of human population growth to the Earth’s resources. 3. proposed measures to lessen population growth and its effect to the Earth’s resources. 4. defined demography and demographic measures. 5. computed for the arithmetic population growth. 6. gathered, organized, and interpreted human population dynamics data (age-sex structure, density, and distribution) 7. constructed and interpreted population pyramid graphs on age-sex structure. As you flip this page, you will be starting with the first lesson of the course. 12 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Lesson 1: Human Population Growth [Week 1] Introduction Undeniably, human population growth has taken the attention of the scientists, economists, and experts in the study of population. Even people like you can observe it. May be questions such as: What is behind these environmental problems? Why is there shortage of food? Why are there millions of people living in poverty?, are being asked. According to Lenntech (2020) human population growth is one of the driving forces behind all these environmental problems, because the growing population demands more and more resources. This lesson leads you to the realization that population growth is true. It is happening, and is rapidly increasing, in fact, it is exponentially growing. Today, you will go through the timeline of exponential population growth. Actually, this lesson will bring you back to the history of population growth, hoping that, as a student, you can be part of the solution to the besetting problems humanity is facing right now. PRIOR TO THE LESSON Pre-Assessment The following items will test your knowledge about human population and human population growth. Write the letter of your answer in the space provide before each item. _____ 1. What is human population? a) A community of different species interacting with one another. b) A group of individuals of the same species living in a particular place. c) A group of individuals of different species living in a particular place and are interacting with one another. d) An individual human being. 13 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) _____ 2. Where did the first modern human evolved? a) Australia c) America b) Europe d) Africa _____ 3. What is the projected human population in 2050? a) about 11 billion c) over 11 billion b) about 8 million d) about 9 billion _____ 4. What was the world’s population 200,000 years ago? a) 70 million c) 1 million b) Over 9.3 billion d) 170 million _____ 5. An S-shaped graph will be achieved when the population a) steadily grows higher c) steadily grows fewer b) gets a zero growth d) gets a steady growth Feedback  1. c  2. d  3. d  4. c  5. c Review Answer this question. Can you identify the different types of graph especially used in the study of population dynamics? 14 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Feedback The following are the possible answers:  Bar graph  Line graph  Pyramid graph  Pie graph Motivation Consider the caption of the picture below, “The World’s population is growing faster than we thought.” If you were to think about this statement, what comes into your mind? Source: https://www.sciencealert.com/the-world-s-population-is-growing-faster- than-we-thought-new-report-finds 15 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) You may write down your answers here. _____________________________________________________________________ _____________________________________________________________________ ____________________________________________________________________. Well, according to experts, human population is growing at a very fast rate. It is even said that it is accelerating at an even greater rate than it was thought it is, if we based it on the previous predictions. According to the Population Reference Bureau (PRB), the world’s population could swell to 9.9 billion by 2050. The planet today is estimated to contain 7.6 billion people and could increase by 33% in 35 years from today (Garfield, L.; 2016). This premise gives us the need to study human population growth in order for humans to act on this, that is, to be able to identify causes of human population growth and as well as describe the possible effects of human population growth to the earth’s resources, and maybe propose measures on how to lessen its growth. Can you give a guess of the Philippines’ human population today? You may browse through the link given below to give you an idea of the Philippines population in real time. https://www.worldometers.info/world-population/philippines-population/ NEW LESSON What is human population? Human population refers to the number of people living in a particular area, from a village to the world as a whole. The number of people living in the Philippines as of July 18, 2020 is 109,643,012. If we compare this data from the one in 1950, there were only about 18,580,480 people living in the Philippines. It is estimated that towards the middle of this year, the human population in the Philippines will reach 110 million. No one knows the population of the earliest humans, but there may have been only a few tens of thousands of individuals that first emerge 200,000 years ago. 16 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Activity Activity 1.1 At this point in time, may I request you to view a video clip on Human Population Through Time. Use the link given https://www.youtube.com/watch?v=PUwmA3Q0_OE to view it. For those who doesn’t have connectivity, you may browse through the title of the video clip, in the USB files provided to you. After watching the video clip, you may answer the questions given here. 1. Where did the first modern human evolved? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 2. When did human begin to migrate? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 3. What was the population 200,000 years ago (BC)? and starting year 1 (AD)? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 4. How do you think did human population grow faster? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 5. What was the projected human population in 2100? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 17 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) 6. What does it mean by leveling off of the human population? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 7. What are the possible effects of the human population growth? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 8. What decisions should humans do to slow down population growth? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 9. Do you think when population growth is lowered down, will it have a corresponding effect to the Earth’s resources? In what manner will it affect? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ Conclusions: Overall, write your conclusions about the human population through time? _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ Note: Please do not flip on the next page if you have not finished answering the questions above. Feedback Activity 1.1 (Answers to Questions) 1. Where did the first modern human evolved?  Africa 18 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem)  Current data suggest that modern humans evolved from archaic humans primarily in East Africa. A 195,000 year old fossil from the Omo 1 in Ethiopia shows the beginnings of the skull changes that we associate with modern people, including a rounded skull case and possibly a projecting chin. Below is the map of Ethiopia showing the exact location of Omo 1. Photo credit: https://www2.palomar.edu/anthro/homo2/mod_homo_4.htm 2. When did humans begin to migrate?  Humans began migrating 100,000 years ago.  You may view the video clip, Map shows how humans migrated across the globe, in this link: https://www.youtube.com/watch?v=CJdT6QcSbQ0  For those who don’t have connectivity, you may view it using the USB provided to you. 3. (a) What was the population 200,000 years ago (BC)? (b) And starting year 1 (AD)?  200,000 years ago – 1 million  1AD – 170 million 19 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) (Illustration taken from Miller, G. & Spoolman S.; 2009, p. 5)  Miller & Spoolman (2009) describes exponential growth as deceptive because it starts off slowly, but after only a few doubling, it grows to enormous number, because each doubling is more than the total of all earlier growth.  Data taken from World Bank and United Nations (Miller, G. & Spoolman, S.; 2009) when plotted shows a J-shaped graph which indicates an exponential growth in the population (refer to the graph above).  Exponential growth in human population means that the number of people increases at a fixed percentage per unit of time. 4. How do you think did human population grow faster?  Human population grew faster during the Industrial Revolution because of the great advances in science and technology: (1) increase in food production and distribution; (2) improvement in public health (water and 20 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) sanitation); and (3) inventions of medical technology (vaccines and antibiotics), along with gains in education and standards of living within many developing nations.  Births significantly outpace deaths on average. 5. What is the projected human population in 2100?  In the video clip, 11 billion was the projected population by 2100 if the population continues to increase by the same rate per unit of time.  However, UN world population projections shows that if assumed that women may continue to have an average of 2.5 children, by 2050 the population may reach 10.8 billion (high), if 2 children – 9.3 billion (medium), or if 1.5 children, then it may reach only 7.8 billion (low). The most likely projection is the medium one – 9.3 billion by 2050. Please refer to graph. (Illustration taken from Miller, G. & Spoolman S.; 2009, p. 125) Projections of the population by 2050. 21 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) 6. What does it mean by leveling off of the human population?  Leveling off of the population may happen when the human population will steadily grow fewer.  As shown in the graph above, an S-shape graph (the green line) will be achieved, if population steadily grows fewer, its levelling off will be possible. 7. What are the possible effects of the human population growth?  A continued rapid increase in human numbers will sooner or later outstrip the resources available on the planet Earth.  There will population catastrophe, more than 1 million people in the world are living in poverty.  Others think that the limit has been exceeded, citing evidence of widespread environmental damage caused by human actions. 8. What decisions should humans do to slow down population growth?  Family planning/Population control 9. Do you think when population growth is lowered down, will it have a corresponding effect to the Earth’s resources? In what manner will it affect?  Decline in population growth may mean reduced consumption of the Earth’s resources. SUBSEQUENT TO THE LESSON Summary Human population is the number of people living in a particular area or locality. World’s human population is growing so fast, according to Miller & Spoolman (2009), it is exponentially growing. This means that human population growth 22 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) started very slow, but after only a few doubling, it grows to enormous number and when plotted on a graph it will show a J-shaped graph. Population projections by 2050 will be high (10.8 billion) if women will have an average of 2.5 children, medium (9.3 billion) for 2 children, and low (7.8 billion) when having 1.5 children. Levelling off of the population may happen when human population steadily grows fewer and the graph may show an S-shaped graph. Human population growth may lead to depletion of natural resources, population catastrophe, meaning, millions of people will be living in poverty, and widespread environmental damage. Family planning/population control can lower down population growth. To lower down population growth means reduced consumption of the Earth’s resources. Reflection At this time, you may now think back and check what you have surmised about the lesson. Please answer the following questions. (1) What is the most important thing I learned personally from the lesson? Why do you think so? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ (2) What do you want to learn more about the lesson? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ (3) What should you do with what you learned today? _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 23 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Post-Assessment View a documentary video in this link https://www.youtube.com/watch?v=NM77ZDak4a8 , it will show you that, truly, the world population is increasing and will reveal the causes of the fast growth in human population. Then answer the following questions: 1. Which part of the video struck you most? Write down a brief information summary of the portion of the video that interests you most. 2. Why did this part of the video interest you most? Write down a brief discussion or a personal reaction about this. Note: You may write your answers in a separate sheet of paper. Feedback Please consider the following criteria in rating your Post Assessment Activity. Score 10 6 2 Criteria Information Summary Identifies a salient Provides a summary of Provides a summary of portion of the video, a salient portion of the a portion, not salient, and summarizes it video. of the video. accurately, descriptively, and concisely. Conceptual Discussion Discussion is mainly Discussion is based on Discussion is based on based on important scientific concepts and personal opinions only. scientific concepts personal opinions. discussed in this lesson. Sentence Structure Sentence effectively Sentence effectively Repeated errors in structured with no structured with 1-2 Sentence structure grammatical, spelling, minor errors in with more than 2 capitalization, and grammar, spelling, errors in grammar, punctuation errors. capitalization, and spelling, capitalization, punctuations. and punctuations. 24 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) References American Museum of Natural History (2016, November 4). Human population through time [Video file]. Retrieved from: https://www.youtube.com/watch?v=PUwmA3Q0_OE Dovers, S. & Butler, C. (2015, July 24). Population and the environment: A global Challenge. Retrieved from: https://www.science.org.au/curious/earth- environment/population-environment Garfield, L. (2016). The world’s population is growing faster than we thought. Retrieved from: https://www.sciencealert.com/the-world-s-population-is- growing-faster-than-we-thought-new-report-finds Lenntech (2020). Population Growth. Retrieved from: https://www.lenntech.com/population-growth-and-environment.htm Miller, G. T. & Spoolman, S. E. (2009). Essentials of Ecology. Brooks/Cole, Cengage Learning. Science Insider (2015, June 3). Map shows how humans migrated across the globe [Video file]. Retrieved from: https://www.youtube.com/watch?v=CJdT6QcSbQ0 Universal fact (2017, October 247). Half of the world’s population growth will be in Africa by 2050 [Video file]. Retrieved from: https://www.youtube.com/watch?v=NM77ZDak4a8 O’Niel, D. (2013). Evolution of Modern Humans: Evolution of Early Modern Homo Sapiens. Retrieved from: https://www2.palomar.edu/anthro/homo2/mod_homo_4.htm 25 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Lesson 2: Human Population Dynamics [Week 2] Introduction Human population trends are necessary because they play a vital role in determining the environmental impact of human activities. Rising population can be attributed to certain parameters such as the demographic and dynamical factors of the population. Birth and death rates, and to include migrants, may trigger the dramatic expansion of the population. In this lesson, you will get to look into certain demographical measures that are contributory to the rate of growth of the population. Dynamical data such as age- sex structure, density, and distribution of human population in certain locality will be explored. You may also learn to compute the population growth rate. PRIOR TO THE LESSON Pre-Assessment Identify with a word or group of words the statement given in Column A. Write your answer in Column B, the blank box next to it. Column A Column B The number of children born to a woman during her lifetime. The number of deaths in one year per 1000 population The spread of people across country. The number of live births in one year per 1000 of the population The number of people residing in an area. 26 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Feedback Column A Column B The number of children born to a Total fertility rate woman during her lifetime. The number of deaths in one year per Death rate 1000 population The spread of people across country. Population distribution The number of live births in one year Birth rate per 1000 of the population The number of people residing in an Population density area. Review Recall our previous lesson. Which among the statements is correct. Why do you think this is correct? 1. J-shaped graph represents a levelling off of population. 2. J-shaped graph represents a declining population. 3. J-shaped graph shows a growth in the population. 4. J-shaped graph represents an exponential population growth. Motivation How do you think can humans slow down population growth? _________________________________________________________ _________________________________________________________ ________________________________________________________. 27 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) NEW LESSON Demography is the scientific study of human populations. It includes population processes that change population size such as births, deaths, and migration. It encompasses the size, distribution, and structure of the population. The population characteristics may allow predictions of the future, more so it may establish relationships with factors such as economic, social, and cultural. Today you will be able to encounter parameters, known as demographic measures, necessary in the study of human population dynamics. Demographic Measures Population size increases because of births and immigration and decreases through deaths and emigration. Human population of countries and cities grow or decline through the interplay of three factors: births (fertility), deaths (mortality), and migration (immigration and emigration). Population change of an area can be computed by subtracting the number of people leaving a population (through death and emigration) from the number entering it (through birth and immigration) during a specified period of time (usually one year). 𝑃𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛 𝐶ℎ𝑎𝑛𝑔𝑒 = (𝐵𝑖𝑟𝑡ℎ𝑠 + 𝐼𝑚𝑚𝑖𝑔𝑟𝑎𝑡𝑖𝑜𝑛) − (𝐷𝑒𝑎𝑡ℎ𝑠 + 𝐸𝑚𝑖𝑔𝑟𝑎𝑡𝑖𝑜𝑛) When births plus immigration exceeds deaths and emigration, population increases, when the reverse happens, population declines. Birth Rate & Death Rate Instead of using the total numbers of births and deaths per year, population experts (demographers) use the birth rate, or crude birth rate, and death rate, or crude death rate. Birth rate is the number of live births in 1 year per 1,000 people in the population. According to the International Encyclopedia of Public Health (2008), 28 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) birth rates are the crucial determinant of population growth (or decline) and age structure of populations have profound socioeconomic implications. Robey, B. (1993) stated that in the mid-60s women in Asia, Africa, and Latin America gave birth to an average of six children. In the 1990s, the average is about four – a drop of one-third. Then eventually, it dropped having an average of 2.1. The number of children per couple is just enough to replace them – thus, a zero population growth. However, Robey mentioned that despite the remarkable decline in birth rates, population continue to grow more rapidly for the past years because the number of women of childbearing age is rising which resulted to high birth rates. Activity Activity 2.1 Year Birth rate Year Birth rate 1. Using the data to your right, 2000 27.85 2011 25.34 plot a line graph of Year vs. Birth Rate 2001 27.37 2012 24.98 with the aid of the computer. 2002 26.88 2013 24.62 2. Based on the plotted graph, 2003 26.30 2014 24.24 what can you say about the birth rate? 2004 25.80 2016 24.00 Increasing or decreasing? Why? 2005 25.31 2018 23.4 2006 24.89 2007 24.48 2008 26.42 2009 26.01 2010 25.68 29 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Feedback Consider the following in rating your output in this activity (Activity 2.1). Score 10 6 4 Criteria Line Graph Plotted the graph Plotted the graph Plotted the graph accurately with accurately inaccurately complete label and neatly drawn. Conceptual Discussion is mainly Discussion is based Discussion is based Discussion of the based on important on scientific on personal opinions answer to the scientific concepts concepts and only. question discussed in this personal opinions. lesson. Sentence Structure Sentence effectively Sentence effectively Repeated errors in structured with no structured with 1-2 Sentence structure grammatical, minor errors in with more than 2 spelling, grammar, spelling, errors in grammar, capitalization, and capitalization, and spelling, punctuation errors. punctuations. capitalization, and punctuations. Death Rate Death rate is the number of deaths in 1 year per 1,000 people in the population. Miller & Spoolman (2009) mentioned that rapid growth of the world’s population over the past 100 years is not primarily the result of the rise in the crude birth rate. Developing countries, primarily, had declined in their crude death rates because people are living longer and fewer infants die due to increase in food supplies and distribution, better nutrition, medical advances, improved sanitation, and safer water supplies. Meaning, life expectancy had increased, from 48 years to 68 years on the average, and infant mortality had decreased in number. Infant mortality is viewed as one of the best indicators of society’s quality of life, since it reflects the country’s general level of nutrition and health care. 30 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Fertility Rate Another measurement used in population studies is fertility rate, the number of children born to a woman during her lifetime. There are two types of fertility rates that affect a country’s population size and growth rate. The first type, called the replacement-level fertility rate, is the average number of children that couples in a population must bear to replace themselves. It is slightly higher than two children per couple (2.1 in developed countries and as high as 2.5 in some developing countries), mostly because some children die before reaching their reproductive years. The second type of fertility rate, the total fertility rate (TFR), is the average number of children born to women in a population during their reproductive years. This factor plays a key role in determining population size. The average fertility rate has been declining. In 2008, the average global TFR was 2.6 children per woman: 1.6 in developed countries (down from 2.5 in 1950) and 2.8 in developing countries (down from 6.5 in 1950). Although the decline in TFR in developing countries is impressive, the TFR remains far above the replacement level of 2.1, not low enough to stabilize the world’s population in the near future. Why has the world’s exponential rate of population growth slowed down in the last few decades? What would have to happen for the world’s population to stop growing? Population Growth Rate Population growth rate (r) is the net number of people added to a population in 1 year per 1000 people already in the population. The following legend will be used in this part of the lesson. Legend: 𝑃𝑜 = 𝑝𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛 𝑎𝑡 𝑡ℎ𝑒 𝑠𝑡𝑎𝑟𝑡, 𝑒. 𝑔. 𝑦𝑒𝑎𝑟 𝑧𝑒𝑟𝑜 𝑃𝑛 = 𝑝𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛 𝑎𝑡 𝑡ℎ𝑒 𝑒𝑛𝑑, 𝑒. 𝑔. 𝑎𝑓𝑡𝑒𝑟 𝑛 𝑛 = 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑖𝑛𝑡𝑒𝑟𝑣𝑎𝑙𝑠 (𝑒. 𝑔. 𝑦𝑒𝑎𝑟𝑠)𝑏𝑒𝑡𝑤𝑒𝑒𝑛 𝑃𝑜 𝑎𝑛𝑑 𝑃𝑛 31 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) For ease in computing for the population growth rate, may we recall the following mathematical formulas:  𝐴𝑏𝑠𝑜𝑙𝑢𝑡𝑒 𝐶ℎ𝑎𝑛𝑔𝑒 = 𝑃𝑛 − 𝑃𝑜 𝑃𝑛 −𝑃𝑜  𝑃𝑒𝑟𝑐𝑒𝑛𝑡𝑎𝑔𝑒 𝑐ℎ𝑎𝑛𝑔𝑒 = ( ) X 100 𝑃𝑜 𝑃𝑛 − 𝑃𝑜  𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝑎𝑛𝑛𝑢𝑎𝑙 𝑖𝑛𝑐𝑟𝑒𝑎𝑠𝑒 = 𝑛 𝑃 −𝑃 ( 𝑛𝑛 𝑜)  𝐴𝑟𝑖𝑡ℎ𝑚𝑒𝑡𝑖𝑐 𝑔𝑟𝑜𝑤𝑡ℎ 𝑟𝑎𝑡𝑒 = X 100 𝑃𝑜 Activity Activity 2.2 Answer this practice problem. A hypothetical population data of an unknown country is given below. (a) Solve for the following: Absolute Change, Percentage Change, Average Annual Increase, and Arithmetic Growth Rate; and (b) Briefly discuss the population growth rate of this unknown country. Given  𝑃𝑜 = 98,787,000 (𝑌𝑒𝑎𝑟 2000)  𝑃𝑛 = 162,356,000 (𝑌𝑒𝑎𝑟 2050)  𝑛 = 50 𝑦𝑒𝑎𝑟𝑠 (𝑚𝑖𝑑 2000 𝑡𝑜 𝑚𝑖𝑑 2050) Feedback Activity 2.2 (Answer) a) 𝐴𝑏𝑠𝑜𝑙𝑢𝑡𝑒 𝐶ℎ𝑎𝑛𝑔𝑒 = 𝑃𝑛 – 𝑃𝑜 = 98,787,000 − 162,356,000 = 63,569,000 32 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) 𝑃𝑛 − 𝑃𝑜 63,569,000 𝑃𝑒𝑟𝑐𝑒𝑛𝑡𝑎𝑔𝑒 𝑐ℎ𝑎𝑛𝑔𝑒 ( ) X 100 = ( ) 100% 𝑃𝑜 98,787,000 = 64.35% 𝑃𝑛 − 𝑃𝑜 63,569,000 𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝑎𝑛𝑛𝑢𝑎𝑙 𝑖𝑛𝑐𝑟𝑒𝑎𝑠𝑒 = = = 1,271,380 𝑛 50 𝑃 −𝑃 ( 𝑛𝑛 𝑜) (63,569,000) 𝐴𝑟𝑖𝑡ℎ𝑚𝑒𝑡𝑖𝑐 𝑔𝑟𝑜𝑤𝑡ℎ 𝑟𝑎𝑡𝑒 = X 100 = 𝑋 100% 𝑃𝑜 98,787,000 = 1.29% b) The projected population growth is 1.29%, which means that the population is increasing by 1.29% each year from year 2000 to the projected year 2050. Human population density Population density is a measurement of the number of people in an area. It is calculated by dividing the number of people by the area of the land (Internet Geography, 2020). The Population density given in the picture to your right is the average population density of the entire Philippines. This is computed by using this formula: 𝑃𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛 𝑑𝑒𝑛𝑠𝑖𝑡𝑦 𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑝𝑒𝑜𝑝𝑙𝑒 = 𝑙𝑎𝑛𝑑 𝑎𝑟𝑒𝑎 If the total population of the Philippines in 2015 is 100, 981, 437 people and the land area is 300,000 km2. Using the formula give above, you will get a population density equal Source: https://psa.gov.ph/content/philippine-population- to 336.60 people/km2 ̴ 337 density-based-2015-census-population people/km.2 33 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Given the data shown in the picture above, what can be said about the population density of the Philippines? You are correct, the population density of the Philippines is increasing. In year 2000 there were 255 people residing in every square kilometer (km2) of land. Furthermore, the data shows that there are more number of people per km2 in the year 2015 than in the year 2010. This represents an increase of 29 persons per km2 between 2010 and 2015. The population density, in 2015, of the two regions in the Philippines such as that of the National Capital Region (NCR), whose population density is 20,785 people/km2, and that of Cordillera Administrative Region (CAR) is 84 people/km2. This may mean that NCR has a greater population density than that of CAR. Why is it that density in NCR different from that in CAR? The answer to this question may come after we have discussed the next topic, human population distribution. Population Distribution Population distribution is the spread of people across the world. The world’s population is spread unevenly across the globe with concentrations of large numbers of people living in the same area. The world as a whole has more ‘empty’ areas than ‘crowded’ areas. There are several physical and human factors to explain this. There are factors, both Physical and human, that are contributory to the distribution of the population. The table below will show you these factors that contributes to the uneven distribution of the population. Physical factors High population density Low population density Topography (Altitude and More people tend to reside in Less people lives in high land, Shape of the land) low land which is flat. like in mountainous areas. Resources Areas rich in resources (like Areas with few resources are coal, oil, fishing) are densely sparsely populated. populated. Climate Areas with temperate climates Areas with extreme climates tend to be densely populated, of hot and cold are sparsely enough rain and heat to grow populated. It is basically crops and conducive for difficult to grow crops and rearing domesticated animals. domesticate animals. 34 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Human Factors High population density Low Population density Political People tend to flock in Unstable government have countries with stable lower density as people tend government. to migrate. Social People wants to live close to People in far-flung areas are each other for security. left isolated. Economic Good job opportunities may Limited job opportunities encourage people to reside, have lesser residents, especially in large cities. especially in remote and mountainous areas. The population density of the Philippines is high, but the population distribution is uneven. Parts of Metro Manila have population density that is 100 times that of some outlying areas such as the mountainous area of Northern Luzon. Again, another table is presented here to compare and contrast population density and population distribution. Population Density vs. Population Distribution Population Density Population Distribution The measure of the number of people that The arrangement of the population in a make up the population in a definite area. certain area in accordance with conditions and requirements of the society. Describes the number of people in a Describes the variability of the spread of the particular population inside a unit area of population in a particular area. land. The Philippines has a population density of The entire Greater Manila is reported to 337 people/km2. contain 22.7 million people which is a quarter of the Philippines’ entire population. The last row of the table above shows that the people in the Philippines are not evenly distributed, in fact there is uneven distribution of people in the entire land area. Why is this so? The Philippines is an archipelago which has over than 7,000 islands that has a total area of 300,000 km2. Most of the islands are small, only a few are larger ones like Luzon and Mindanao, which accounts for a larger portion of the surface area. While some islands are highly populated than others, the bulk of people are residing in Luzon and Mindanao areas. The distribution of people in the entire Philippines is uneven, a lot are in the Luzon area, most are in the Greater Manila, and in the Mindanao islands, the bulk of 35 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) people are in Davao City (World Population Review, 2020). Age and Sex Age and sex, one of the many demographic variables, are arguably the most important and relevant to demographers. Horiuchi and Preston (cited in Poston, 2005) stated that the interaction of the demographic processes, such as fertility, mortality, migration, and growth, produces the age and sex structure of the population. Reciprocally, this age and sex structure of a population, in itself, affects the interaction of these demographic processes. Population Reference Bureau (2019) defines age structure as the proportion of the total population in each age group. Davis & Morduck (cited in Poston, 2005) stated that the distribution of the age groups (infant, young, adult, etc.) and sex (male or female) of the population defines the division of labor in traditional societies. Moreover, Keyfitz & Flieger (cited in Poston, 2005) mentioned that changes in the age distribution of a population have consequences for educational, political, and economic life. SUBSEQUENT TO THE LESSON Summary Population size increases because of births and immigration and decreases through deaths and emigration. Population change of an area can be computed by subtracting the number of people leaving a population (through death and emigration) from the number entering it (through birth and immigration) during a specified period of time (usually one year). When births plus immigration exceeds deaths and emigration, population increases, when the reverse happens, population declines. Birth rate is the number of live births in 1 year per 1,000 people in the population. 36 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Death rate is the number of deaths in 1 year per 1,000 people in the population. There are two types of fertility rates that affect a country’s population size and growth rate. The first type, called the replacement-level fertility rate, is the average number of children that couple in a population must bear to replace themselves. The second type of fertility rate, the total fertility rate (FTR), is the average number of children born to women in a population during their reproductive years. Population growth rate (r) is the net number of people added to a population in 1 year per 1000 people already in the population. Population density is a measurement of the number of people in an area. Population distribution describes the variability of the spread of people across the world. Age structure is the proportion of the total population in each age group. Age and sex structure and the demographic processes relates with each other by reciprocity. Reflection 1. As a student, why do you need to learn about the factors that may affect the size of the population? ____________________________________________________________ ____________________________________________________________ ____________________________________________________________ 2. How can you help to slow down human population growth? ____________________________________________________________ ____________________________________________________________ ____________________________________________________________ 37 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Post-Assessment 1. Identify at least three factors that may affect human population growth or decline. Why do you think these can contribute to population growth or decline? ____________________________________________________________ ____________________________________________________________ ____________________________________________________________ 2. How can age-sex structure of a population define the future of the society? Please discuss at least two examples. ____________________________________________________________ ____________________________________________________________ ____________________________________________________________ Feedback Consider this Rubric to check for your answers. Score 10 6 4 Item # 1 Identified at least Identified at least 2 Identified at least 1 three factors, factors, discussed factor, discussed how discussed how these how these factors this factor contributed factors contributed to contributed to to population growth population growth or population growth or or declined using declined using declined using personal opinions scientific concepts scientific concepts only. discussed in this and personal lesson. opinions. 2 Explained thoroughly, Explained Explained ideas/ concisely, and ideas/information information asked for, accurately the asked for, using using personal ideas/information scientific concepts in opinions only. asked for, using this lesson and scientific concepts personal opinion. No example was discussed in this given. lesson. Discussed at least 1 example to support Discussed at least 2 the explanation. examples to support the explanation. 38 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) References International Encyclopedia of Public Health (2008). Birth rate. Retrieved from: https://www.sciencedirect.com/topics/agricultural-and-biological- sciences/birth-rate Internetgeography.net (2015). Retrieved from: https://www.internetgeography.net/topics/what-is-population-density/ Miller, G. T. & Spoolman, S. E. (2009) Essentials of Ecology. Brooks/Cole, Cengage Learning. Philippine Statistics Office (2020). Philippine Population Density (Based on the 2015 Census Population. Retrieved from: https://psa.gov.ph/content/philippine-population-density-based-2015-census- population Robey, B. (1993). The birth rate decline in developing countries. Sage Journals, 22(4), 221-224. Retrieved from: https://journals.sagepub.com/doi/pdf/10.1177/003072709302200403 Poston, D. (2005). Age and sex. Handbook of population. Retrieved from: https://link.springer.com/chapter/10.1007%2F0-387-23106-4_2 Crossman, A. (2019, September 28). Age structure and age pyramids: An overview of the concept and its implications. Retrieved from: https://www.thoughtco.com/age-structure-definition-3026043 39 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Lesson 3: Population Pyramid: The shape of the society’s population [Week 3] Introduction Two of the most common variables necessary in the study of population dynamics are age and sex of individuals within a given area. Population Reference Bureau (2019) stated that age-sex structure is the composition of a population as determined by the number or proportion of males and females in each category. These data on age-sex structure are used to construct population pyramid, which is one of the most visual representation of the population. The resulting shape of the graph can tell much about what is happening in the population (SDSU, Census Data Center, 2020) The population pyramid, also known as the age-sex pyramid, is a “snapshot” of a population in time. It shows how the population are distributed among age and sex categories (Khan Academy, 2020). This population pyramid takes various shapes. The types of population pyramid, as well as its interpretation will be learned in the succeeding pages of this module. PRIOR TO THE LESSON Pre-Assessment Write TRUE if the statement is correct and FALSE if otherwise in the space provided before each item.. _____ 1. Age and sex data are not given importance in the study of population dynamics. _____ 2. The shape of the population pyramid defines the future of the population. 40 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) _____ 3. A constrictive population pyramid has broad base and narrow top. _____ 4. An expansive population has high birth rates as well as high death rates. _____ 5. Developing nations would take the shape of a stationary pyramid. Feedback Check if you have previous knowledge about the next lesson. 1. FALSE 2. TRUE 3. FALSE 4. TRUE 5. FALSE Review Write the letter of your answer in the space provided before each item. _____ 1. It is the variability of the spread of the population in the entire country. a) density c) age-sex structure b) distribution d) birth rate _____ 2. Which among parameters can determine the growth or decline of the population? a) Deaths and emigration c)deaths only b) Births and immigration d) births only _____ 3. The total population divided by the total land area. a) Fertility rate c) birth rate b) Density d) distribution 41 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) _____ 4. Which among the choices is a not directly influenced by age and sex? a) mortality c) fertility b) migration d) distribution _____ 5. Which of the choices is a physical factor that contributes to the uneven distribution of the population on Earth? a) Political b) economic c) social d) climate Motivation How do you think can age and sex affect the labor force in a population? Why? _______________________________________________________________ _______________________________________________________________ NEW LESSON Age-Sex Structure Age-sex structure refers to the number of individuals of sex and age group in the population. The numbers of males and females in young, middle, and older age groups determine how fast a population grows or declines. It is represented by a special type of graph called population pyramid. Types of population pyramids Population pyramid tells us of the shape of the population. Bezy (2016) mentioned that population pyramid is a graphical representation of the age and sex composition of the population. On the other hand, Preshoff (2014) said that population pyramids are not only powerful predictors of the future, but it gives us a record of the past. Furthermore, it may also provide insights about political and social stability, and economic development of a population (Wakim & Grewal, 2020). 42 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Boucher (2016) discussed the three types of population pyramids, namely: expansive, constrictive, and stationary. 1. Expansive Expansive population pyramid is used to describe populations that are young and growing. They are often characterized by their typical ‘pyramid’ shape, which has a broad base and narrow top. Expansive population pyramids show a larger percentage of the population in the younger age cohorts, usually with each age cohort smaller in size than the one below it. These types of populations are typically representative of developing nations, whose populations often have high fertility rates and lower than average life expectancies. 2. Constrictive Constrictive population pyramid is used to describe populations that are elderly and shrinking. It can often be seen like beehives and typically have an inverted shape with the graph tapering in at the bottom. It represents a smaller percentages of people in the younger age cohorts and are typically characteristic of countries with higher levels of social and economic development, where access to quality education and health care is available to a large portion of the population. 43 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) 3. Stationary Stationary or near stationary population pyramid is used to describe a population that is not growing. They are characterized by their rectangular shape, displaying somewhat equal percentages across age cohorts that taper off toward the top. These pyramids are often characteristic of developed nations, where birth rates are low and overall quality of life is high. Interpretation of Population Pyramids of some countries Wakim & Grewal (2020) provided examples of the population pyramids of some countries and its interpretation. The population pyramid of Nigeria (2015) has a broad base of young children and tapered sides showing rapidly decreasing numbers of people at older ages. This represents an expansive population. This reflects a population that has a high birth rates and relatively high death rates. Nigeria is typically a developing nation that has very high fertility rate and has an overall low quality of life. 44 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) This next graph is owned by France (2015), showing a narrow base of children and young adults, reflects relatively low birth rate over the past several decades. There is a bulge of people in mid-to-adulthood, an evidence of higher birth rates in previous generations (the post-World II baby boom) coupled with low death rates. Also, there is a larger proportion of females than males at older ages, which is especially pronounced, that it is due to the higher rates of death of males than females. The last example that will be presented here is the population pyramid of Egypt (2010). The 2010 population pyramid of Egypt has a youth bulge in the young adult age groups. The “Youth Bulge” shown in the graph depicts a disproportionately large cohort of young adults, in which this age groups typically enter the labor force and electorate. Thus, the social, political, and economic implications are, there will be high rates of unemployment, as well as social and political alienation. These conditions, in turn, may result in a heightened risk of violence and political instability. 45 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) A youth bulge has been posited as an important contributor to the rise of fascism in the 20th century Europe, the spread of communism during the Cold War, and the events of the Arab Spring, which began in Egypt in 2011. If you would like to know more about Arab Spring you may browse through this link: https://www.history.com/topics/middle-east/arab-spring At this point, now that you already know how to interpret the different types of population pyramid, you may now proceed to the next activity. Activity Activity 3.1 Before starting off with this activity, please view the video in the link given below, to give you an overall understanding of the population pyramids and its interpretation.https://www.youtube.com/watch?time_continue=7&v=RLmKfXwWQtE &feature=emblogo If you do not have connectivity, you may look for the video in the USB provided to you. If you are done viewing the video, you may now perform the activity. Make a population pyramid using the Philippines’ population data given below. Properly label your graph. Interpret it in terms of births, deaths, political, economic, social, and cultural conditions of the Philippines’ population for the year 2018. The guide questions below may help you analyze your population pyramid. 1. What is the shape of the population pyramid? 2. What information or unique scenario that can be taken from the graph? 3. Can you briefly discuss the birth and death rates of the population using the graph? 4. What are the implications of such scenario in the political, economic, social, and even cultural conditions of the population? 46 Manajero, Angeles, Banquillo, Monroy, & Verzo  West Visayas State University/2020 NCSI 111 (People and the Earth’s Ecosystem) Below is the date of the age and sex structure of the Philippines in 2018. Age Group Male Female Age Group Male Female 0-4 years 5,875,800 5,555,500 44-49 2,832,400 2,780,800 5-9 5,646,200 5,368,700 50-54 2,465,500 2,453,000 10-14 5,379,500 5,105,400 55-59 2,012,100 2,055,200 15-19 5,253,000 4941,400 60-64 1,531,000 1,633,900 20-24 5,067,100 4,825,200 65-69 1,055,400 1,213,400 25-29 4,599,100 4,448,800 70-74 652,300 842,300 30-34 3,979,700 3,889,900 75-79 373,200 554,400 35-39 3,543,200 3,474,400 80 + 315,000 567,800 40-44 3,192,300 3,115,700 Feedback Consider this Rubric in rating your output in this activity (Activity 3.1). Score 10 6 2 Criteria Pyramid Graph Plotted the graph Plotted the graph Plotted the graph accurately with accurately inaccurately complete label and neatly drawn Conceptual Discussion is mainly Discussion is based Discussion is based Discussion of the based on important on scientific on personal opinions answer to the scientific concepts concepts and only. questions discussed in this personal opinions. lesson. Sentence Structure Sentence effectively Sentence effectively Repeated errors in structured with no structured with 1-2 Sentence structure grammatical, minor errors in with more than 2 spelling, grammar, spelling, errors in grammar, capitalization, and capitalization, and