Human Population – Growth & Age Structure (4.2) State Standard SB4A. Investigate the relationships among organisms, populations, communities, ecosystems, and biomes. SB4D. Assess and explain human activities that influence and modify the environment such as global warming, population growth, pesticide use, and water and power consumption.

Activator: What can be learned from this graph about Kenya?

What event caused human population’s lag phase to end?

Chapter 4 Population Ecology 4.2 Human Population Human Population Growth Rate The human population experienced exponential growth as humans benefitted from the Industrial Revolution, improved food production, improved health care, & disease cure/prevention

What trend does this graph reveal about human population growth? Why do you think this is?

Chapter 4 Population Ecology 4.2 Human Population Human Population Growth Rate Cont’d Although the human population is still growing, the rate of its growth has slowed. Diseases like AIDS & also voluntary population control have contributed to this slowing.

Population trends can be altered by events such as disease and war. Chapter 4 Population Ecology 4.2 Human Population Trends in Human Population Growth Population trends can be altered by events such as disease and war. Human population growth is not the same in all countries.

Chapter 4 Population Ecology 4.2 Human Population Trends in Human Population Growth Cont’d Zero population growth (ZPG) occurs when the birthrate equals the death rate. The age structure eventually should be more balanced with numbers at pre-reproductive, reproductive, and post-reproductive ages being approximately equal.

Trends in Human Population Growth Cont’d Chapter 4 Population Ecology 4.2 Human Population Trends in Human Population Growth Cont’d Age Structure A population’s age structure is the number of males and females in each of three age groups: pre-reproductive stage, reproductive stage, and post- reproductive stage.

What inferences can you make about specific human population groups by reading this graph?

Trends in Human Population Growth Cont’d Chapter 4 Population Ecology 4.2 Human Population Trends in Human Population Growth Cont’d Human Carrying Capacity Scientists are concerned about the human population reaching or exceeding the carrying capacity. An important factor is the amount of resources from the biosphere that are used by each person.

When does zero population growth occur? Chapter 4 Population Ecology Chapter Diagnostic Questions When does zero population growth occur? when birth rate equals death rate when death rate exceeds birth rate when birth rate exceeds death rate when there are zero births A B C D CDQ 3

decreased agriculture famine and wars setbacks in medicine Chapter 4 Population Ecology 4.2 Formative Questions Which is a primary reason for the decline in the percent growth of the human population after 1962? decreased agriculture famine and wars setbacks in medicine voluntary population control A B C D FQ 5

Chapter 4 Population Ecology 4.2 Formative Questions What will happen to the human population when the birthrate equals the death rate? CDC HPG PGR ZPG A B C D FQ 6

Which type of population growth model does this graph represent? Chapter 4 Population Ecology Chapter Assessment Questions Which type of population growth model does this graph represent? exponential spatial genetic logistic A B C D CAQ 1

Chapter 4 Population Ecology Chapter Assessment Questions Based on the information in the graph, infer which statement accurately represents the information provided. India has very little land for farming. Germany is smaller per acre than the United States. More land is used to support an individual in the United States. A person in Indonesia requires more land than a person in Brazil. A B C D CAQ 2