Unit 3 Lesson 4

Lesson 4 1.How Many People Can Earth Hold? 2.Developed vs Developing 3.Age Structures 4.Life Expectancy & Life Span 5.Emigration vs Immigration 6.Population Growth Through History 7.Demographic Transitions Unit 3

How Many People can Earth Hold? * Human population reached 7 billion in 2011 * By 2025, the population will reach 8.1 billion * Human Carrying Capacity is unknown, and scientists do not agree on a common number. For most species, there are four variables that factor into calculating carrying capacity: food availability, water supply, living space, and environmental conditions. In the case of humans, the arithmetic is much, much more complicated. Humans are affected by a large multitude of unique variables including technological advancement, sanitation, energy consumption, economics, and medical advancements. If current fertility, mortality, and migration trends hold, we will reach 9.6 billion in 2050 with most growth coming from Africa.

Developed vs Developing Developed Countries/More Developed Countries (MDC) - Norway, Australia, Switzerland, Netherlands, US, Germany, Denmark, Japan, Israel, France, Finland, Italy, Spain Higher life expectancy More education More money (income) & GDP/GNP Developing Countries/Less Developed Countries (LDC) - Latin America, China, Haiti, India, most countries in Africa, Afghanistan, Syria, Peru Lower life expectancy Less education Less money (income) & GDP/GNP 1/5 of world’s population lives in absolute poverty, illiterate, lack clean H 2 0, & don’t have enough food 80% of world’s population live in developing countries & increasing

Age Structures Age structure categories Pre-reproductive ages (0-14) Reproductive ages (15-44) Post-reproductive ages (45 and older) Pre-Reproductive Ages Reproductive Ages Post-Reproductive Ages

Age Structures Age Structure - A population pyramid is a graphical illustration that shows the distribution of various age groups in a population which forms the shape of a pyramid when the population is growing. Expanding Population Young (pre-reproductive) dominates population Has population momentum- more children will move up to become reproductive Potential for rapid increase in birth rates once the youngsters reach reproductive age. EX: Developing countries- many countries in Africa & India

Age Structures Stable Populations Birth rates = death rates All age groups are about equal EX: Most Western European countries & U.S.

Age Structures Declining Populations Birth rates are lower than death rates Many more older people who are not reproducing Population will become much smaller when they die. EX: Russia, Japan, Italy, & Germany

Life Expectancy & Life Span Life Expectancy – The average age a newborn can expect to attain any given society – Declining mortality is the primary cause of most population growth in the last 300 yrs. Life expectancy was around 40. – In 2015, the Worldwide average is about 70 years old. – In 2015, US ranks 53 rd with a life expectancy of 78.8 yrs old – Monaco ranks 1 st with a life expectancy of 89.5yrs old (Japan 2 nd ) – South Africa ranks last with a life expectancy of 49.7 yrs old Life Span - The amount of time that a person or animal actually lives. Herriot the turtle lived to 175 yrs old Jeanne Calment of France

Emigration vs Immigration Emigration - The movement of people out of a country Immigration – the movement of people into a country Why People Emigrate or Immigrate? 2.Environmental Refugees - No longer able to farm due to change in weather/climate - Homes destroyed by hurricane, tsunamis cause people to flee homes 1.Seeking political or economic asylum from home country -Political Wars & social strife (genocide) -No jobs or poor economy Hit “ENTER” 3. Forced Migration – “Transmigration” - Example: Indonesia- 1970’s - Moved 65 million people from overcrowded islands of Java & Bali to less populated Sumatra, Borneo & New Guinea - Attempts at farming the rainforest failed - Ended in economic & environmental disaster - Rainforests were destroyed & people were no better off. - Threatened biodiversity of region

Domestication of plants & Animals Agriculturally based urban societies Industrial & Scientific Revolution Black Death Calculate how old you will be in 2050!

Demographic Transition Demographic Transition – Refers to the transition from high birth and death rates to low birth and death rates as a country develops from a pre-industrial to an industrialized economic system.

Demographic Transition Stage 1: Preindustrial High birth rates, high (at time erratic/up & down) death rates, low growth rates Illiterate, poor, rural, hunter/gather society Stage for much of human history & traditional societies like a few isolated tribes in Brazil Practically no country today

Demographic Transition Stage 2: Transitional High birth rates, declining death rates, rising growth rates/population explosion Developing Countries & Agriculture Revolution Improvements but not the best in sanitation (water), food supply & medicine Much of Africa today, some countries of Asia (Afghanistan, Nepal, Laos etc.)

Demographic Transition Stage 3: Industrial Continued decline of death rates, declining birth rates, growth rates slowing but not much due to high life expectancy Change in behavior: Increased female literacy, employment, & empowerment, lower infant mortality rate Economic change: urbanization (incentive to have fewer children) Currently Mexico & some of India

Demographic Transition Stage 4: Postindustrial Low birth rates, low death rates, low growth rates United States, Canada, Australia, China Stage 5: Low birth rates, rising death rates, declining growth rates (if birth rates drop below death rates = negative growth rate) Countries who have sub-replacement fertility (less than 2.1 children per woman) Italy, Japan, & Germany

End of Unit 3 Lesson 4