Human population growth
Upcoming SlideShare
Loading in...5

Human population growth






Total Views
Views on SlideShare
Embed Views



1 Embed 2 2



Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
Post Comment
Edit your comment

    Human population growth Human population growth Presentation Transcript

    • Human Population Growth Dr. Mark A. McGinley Honors College and Department of Biological Sciences Texas Tech University
    • Human Population Growth• Reached 1 Billion – 1830• Reached 2 Billion – 1930• Reached 3 Billion – 1960• Reached 4 Billion – 1975• Reached 5 Billion – 1987• Reached 6 Billion – 1999• Reached 7 Billion – 2011
    • Current Estimated Human Population• Monday February 4, 2013 – 1:40 PM• World 7,064,109,760 people• html
    • Approximate Estimates Worldwide• 5 births per second• 2 deaths per second• dN/dt = 3 individuals per second• = 10,800 inviduals per hour• Add new Lubbock (N = 230,000 ind) in less than 1 day!!!
    • Human Population Growth• As human population size has increased there has not been a decline in the per capita growth rate – As populations have gotten larger humans have not been forced to have lower per capita birth rates – As populations have gotten larger humans have not been forced to have higher per capita death rates
    • What’s Up With Humans?• Humans can alter the world in ways that no other species on the planet can. – 1. increase food production • Agriculture – Irrigation, fertilization, farm more area, mechanization, crop improvement • Interestingly, the proportion of people who are starving on the planet is about the same to day as it was in the mid 1800s (20%)
    • What’s Up With Humans?– 2. Modern medicine • Decreased juvenile mortality • Increased longevity– 3. Better public health • Waste disposal • Clean water– 4. Don’t worry too much about predators • Occasional shark or cougar attack
    • Human Population Growth Problem?• Benefits of Population Growth??• Disadvantages of Population Growth??
    • Human Numbers Through Time• ange2/current/lectures/human_pop/human_ pop.html• aYc
    • Where is Human Population Growth Occurring?• Most population growth is occurring in developing countries.
    • Potential Problems With High Human Population Growth Occurring in Developing Countries• Environmental problems – Most developing countries located in the tropical regions – Habitat destruction, overharvesting, and pollution can cause extinction in the two most diverse ecosystems on the Earth • Tropical Rainforests • Coral Reefs
    • Deforestation in Borneo
    • Hunger
    • Food-related Problems?
    • Childhood Obesity in the USA
    • Weight Loss Products • Weight Loss is a 60 Billion Dollar industry in the USA
    • Pudgy Pets
    • Access to Freshwater
    • World Poverty
    • Child Labor
    • Urbanization
    • Urbanization- India Photo by Honey Blakeman
    • Human Population Growth• Human populations have basically stabilized in developed countries but are still increasing in developing nations• Why??
    • Demographic Transition
    • Demographic Transition• Pre-industrial societies – High per capita death rates offset by high per capita birth rates • Slow population growth• Transitional societies – Per capita birth rates have remained high while per capita death rates have fallen • Rapid population growth• Post-industrial societies – Low per capita death rates and per capita birth rates • Slow population growth
    • What Causes Per Capita Birth Rates to Decline in Industrialized Societies?
    • Literacy Rate vs. Birth rate
    • Worldwide Literacy
    • Fertility Rate vs GDP
    • What Will Happen to Human Population Size in the Future???• Human demographers predict that once all countries have completed the demographic transition that Earth’s population will stabilize. – When and how large?
    • Factors Increasing Mortality Rates HIV/AIDS
    • HIV in Africa