1. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings PowerPoint Lectures for Biology, Seventh Edition Neil Campbell and Jane Reece Lectures by Chris Romero Chapter 52 Population Ecology – What is a population???

2. LE 52-3a For many animals, such as these wolves, living in groups increases the effectiveness of hunting, spreads the work of protecting and caring for young, and helps exclude other individuals from their territory.

3. LE 52-3b Birds nesting on small islands, such as these king penguins on South Georgia Island in the South Atlantic Ocean, often exhibit uniform spacing, maintained by aggressive interactions between neighbors.

4. LE 52-3c Dandelions grow from windblown seeds that land at random and later germinate.

5. LE 52-5 III II 100 Percentage of maximum life span Number of survivors (log scale) 0 50 1,000 100 10 1 I

6. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Life History Diversity Life histories are very diverse Species that exhibit semelparity, or “big-bang” reproduction, reproduce once and die Species that exhibit iteroparity, or repeated reproduction, produce offspring repeatedly

7. LE 52-13a Time (days) Number of Paramecium/mL 1,000 0 400 5 200 10 0 15 800 600 A Paramecium population in the lab

8. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Density-Dependent Population Regulation Density-dependent birth and death rates are an example of negative feedback that regulates population growth They are affected by many factors, such as competition for resources, territoriality, health, predation, toxic wastes, and intrinsic factors

9. LE 52-18 1960 Year Moose population size 2,500 Steady decline probably caused largely by wolf predation 2,000 1,500 1,000 500 0 1970 1980 1990 2000 Dramatic collapse caused by severe winter weather and food shortage, leading to starvation of more than 75% of the population

10. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Extreme fluctuations in population size are typically more common in invertebrates than in large mammals

11. LE 52-21 Year Hare population size (thousands) 1850 Snowshoe hare 0 1875 1900 1925 40 80 120 160 Lynx population size (thousands) Lynx 0 3 6 9

12. LE 52-22 8000 B.C. Human population (billions) 6 5 4 3 2 1 0 4000 B.C. 3000 B.C. 2000 B.C. 1000 B.C. The Plague 0 1000 A.D. 2000 A.D.

13. LE 52-25 Rapid growth Afghanistan Age Male Percent of population Female 86 42 24 68 0 45–49 40–44 35–39 30–34 25–29 20–24 15–19 10–14 5–9 0–4 85+ 80–84 75–79 70–74 65–69 60–64 55–59 50–54 Slow growth United States Age Male Percent of population Female 6 42 24 68 0 45–49 40–44 35–39 30–34 25–29 20–24 15–19 10–14 5–9 0–4 85+ 80–84 75–79 70–74 65–69 60–64 55–59 50–54 8 Decrease Italy Male Percent of population Female 6 42 24 68 0 8

14. LE 52-27 Ecological footprint (ha per person) 14 12 10 8 6 4 16 0 2 0 24 6 8 1012 14 16 Available ecological capacity (ha per person) New Zealand Australia Canada Sweden World China India Spain UK Japan Germany Norway USA Netherlands