Book contents
- Frontmatter
- Contents
- Preface and acknowledgements
- Part one Reproductive biology
- Part two Reproduction and social issues
- 13 Population dynamics, stress and the general theory of adaptation
- 14 Extinctions and the conservation of endangered species
- 15 Artificial control of fertility
- 16 Hormonal contributions to errors of sexual differentiation
- 17 The acquired immunodeficiency syndrome (AIDS) epidemic: a global emergency
- 18 The effect of nutrition and exercise on the hypothalamic–pituitary–gonadal axis
- 19 Principles of teratology and an update on nicotine, ethanol and caffeine abuse
- 20 Ethical aspects of human reproductive biology
- Index
13 - Population dynamics, stress and the general theory of adaptation
Published online by Cambridge University Press: 05 June 2012
- Frontmatter
- Contents
- Preface and acknowledgements
- Part one Reproductive biology
- Part two Reproduction and social issues
- 13 Population dynamics, stress and the general theory of adaptation
- 14 Extinctions and the conservation of endangered species
- 15 Artificial control of fertility
- 16 Hormonal contributions to errors of sexual differentiation
- 17 The acquired immunodeficiency syndrome (AIDS) epidemic: a global emergency
- 18 The effect of nutrition and exercise on the hypothalamic–pituitary–gonadal axis
- 19 Principles of teratology and an update on nicotine, ethanol and caffeine abuse
- 20 Ethical aspects of human reproductive biology
- Index
Summary
A DEMOGRAPHY AND STRESS: ADAPTATION AND STRESS
Currently the two greatest problems facing humankind, problems which link environmental, health and social issues, are population growth and the urgent need for its control. As Paul Ehrlich (from Stanford University) has stated so succinctly: ‘We are now in charge of the planet, but we are not behaving as if we know we are in charge of the planet’. Certaintly, we are not behaving in a manner that befits our special responsibilities, and, further, it seems that we are unwilling or unable to cope with our increasing numbers and the effect this increase has on our environment. The world's population is currently increasing at a rate of 90–100 million people a year, an increase of more than 10000 people every hour. In 1990 there were over 5 billion people on this planet. As a species, it took 4 million years for the world's population to grow from just over zero to 2 billion in 1932. Then, in less than six decades, it reached the 1989 figure of 5.2 billion. The present projection tells us that there will be more than 6 billion humans by the year 2000 and 7 billion by 2010 (Fig. 13.1). The impact of a growth rate can be better appreciated by the time taken for the population to double its size. Table 13.1 shows the approximate doubling times at various growth rates. Growth rates of 2% (a doubling time of 35 years) is particularly relevant since large parts of the world have a growth rate close to 2%.
- Type
- Chapter
- Information
- A Guide to ReproductionSocial Issues and Human Concerns, pp. 225 - 248Publisher: Cambridge University PressPrint publication year: 1994
- 2
- Cited by