Edward J. Maruska

Although extinction of plant and animal species has always occurred, many scientists today believe that human activity has accelerated extinction rates. In the following viewpoint, Edward J. Maruska, executive director of the Cincinnati Zoo and Botanical Garden, estimates that one hundred plant and animal species may be lost per day. Maruska argues that phenomenal human population growth causes the destruction of habitats and the overhunting that leads to extinction. When one species becomes extinct, he contends, other species follow, creating a “domino effect” which can destroy the natural balance on which humans depend for survival.

As you read, consider the following questions:

1. According to Maruska, how many animal species were lost each day from 1990 to 1995?
2. Why, according to Maruska, are island species more vulnerable to extinction?
3. How much of the world’s rain...