Ch.5 Populations and Communities

Chapter Overview

Chapter 5 takes a look at ecosystems from a bigger picture. Why are there more fish in the sea than all animals on land? Why do cats and dogs have five or six babies at a time, but elephants and humans only have one? We'll explore these questions and what makes populations change over time. There's only one type of animal in the world whose population growth isn't limited by the environment - humans. How long can we sustain it?