Chapter 5

Chapter Resources
(A website with worldwide statistics on human populations)

Hydrilla as an Invasive Species
(Cornell Univ.)

US Age Structure DIagrams
(an animated chart showing how the US population's age structure has changed from 1950 to 2010)



Interdependence in Nature
Q: What factors contribute to changes in populations?

Think about it - In the 1950s, a fish farmer in California tossed a few plants called hydrilla into a canal. He assumed it was harmless. Boy, was he wrong!

Key Questions Include:

How do ecologists study populations?
What factors affect population growth?
What happens during exponential growth?
What is logistic growth?
What factors determine carrying capacity?
What limiting factors depend on population density?
How has the human population size changed over time?
Why do population growth rates differ among countries?

A Plague of Rabbits

In 1859, an Australian farmer released 24 wild European rabbits from England on his ranch. "A few rabbits" he said, "could do little harm and might provide a touch of home, in addition to a spot of hunting."Seven years later, he and his friends shot 14,253 rabbits!


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Special Feature on Invasive Species

(from p. 136)