LS: I will be able to explain the historical progression of population growth LS: I will be able to identify and explain the factors that affect the distribution of a growing population POPULATION ECOLOGY

1. World population has experienced continuous growth since the 1350 – Great Famine and the Black Death (370 million) 2. The projected global population for 2050 by the UN as of 2012: between 8.3 and 10.9 billion World Population Are these population number possible? What concerns as members of the human race should we have?

The Rise of Human Populations! Early man: Had colonized most if not all of the “ice- free” globe by the end of the last ice age ( years ago) Were hunters, gathers, and generally nomads Development of Agriculture: 1)Development of the wheel 2)Planting of crops 3)Humans began to settle into permanent settlements 4)Increased security and productivity (manufactured goods) 5)Complex economy and social structure 6)Distinct cultures and religions 7)Sophisticated language and writing systems Neolithic Revolution

How did the establishments of empires affect population growth? Mesopotamia brought us: 1.Cuneiform writing- system of pictographs 2.Transportation by waterways 3.Access to Mediterranean Sea: fostered the projection of military power, exchange of goods, and exchange of ideas and invention 4.New land technologies: horse-based cavalry and chariots Led to the rise of Empires

What is taking place during the 7 th century? Middle East: Islamic Civilization grew and expanded based on merchant economy Medieval Europe: 1)Society is based on agricultural landholdings and nobility 2)Period of the Crusades 3)Late period is marked by famine, plague, and war (Black Death killed about 1/3 of the population between )

What has resulted from the Scientific and Industrial Revolutions? Both began in Europe 1. Enjoyed technological advantages: cast-iron production, piston bellows, suspension bridge construction, printing and the compass 2. Maritime superhighways fostered the exchange of goods, people, inventions, and ideas

3. Improved methods in irrigation and farming, new crop development, use of horsepower in fields 4. Implementation of the factory system, employment of women and children, new inventions (flying shuttle, spinning jenny, roller spinner) 5. Railroads and steam engines How did this progression in human establishment affect population growth?

Since the 18 th Century….populations have grown at a faster rate because…. Decline of death rate Increase in birth rate Elimination of plagues Increase in food availability Better living conditions Vaccines Hygiene Healthy diets Medical Advancements More education Accessible water

1) After what event in European history did the Earth’s population begin to see continuous growth? ________________________ 2) Early man were known as _____________ and _______________; generally roaming from place to place. 3) Why was the development of agriculture significant in population growth? Checking for Understanding…

What are features of populations? Remember a population is all the members of a species living in the same place at the same time. Population size: refers to the total number of organisms in the population Population size can be changed through migration Immigration Emigration What is the difference between immigration and emigration?

Growth rate is __________________ minus the ________________ Population density Population dispersion The number of individuals per unit area or volume The relative distribution or arrangement of its individuals

How fast can a population grow? The population’s rate is limited by the maximum number of offspring that each member of the population can produce— reproductive potential 1.Will increase when individuals produce more offspring at a time 2.Produce earlier in life, shortening the generation time Exponential Growth states that populations will grow faster and faster 1.Occurs in nature when populations have plenty of food, space, and little to no competition or predators 2.Environment prevents this from happening

Carrying Capacity and Regulating population Growth The carrying capacity for a particular species is the maximum population that the ecosystem can support indefinitely 1.A population can increase beyond this point, but it is difficult to maintain 2.The production of natural resources are limiting factors. 3.Competition within groups and between groups will affect carrying capacity

Independent vs. Dependent Density Dependent Regulation Density Independent Regulation Regulation happens when population are crowded—limited resources, predation, and disease Regulation occurs regardless of population size/density— severe weather, natural disaster

1) The number of individuals per unit are is called population ___________, but the relative distribution of it group members is called _______________. 2) With unlimited supplies, space, and no predators or competition _____________ growth will occur. 3) Hurricanes, earthquakes, and tornadoes are examples of _________________ regulation. Checking for Understanding…