On the Galápagos Islands, the finches that Darwin studied tended to have either small beaks or large beaks. The smaller beaks are best at eating soft seeds but are ineffective at cracking large seeds. The larger beaks are best at cracking hard seeds. Beaks of intermediate size are inefficient for either seed type. Which result of natural selection is at work in this example?

   _____ is one of the most common chronic childhood diseases in the United States and other developed nations and a major cause of childhood disability.

   Which statement related to the health consequences of air pollution is FALSE?

   What percentage of the world’s population breathes polluted air?

  The EROEI must be _____ for any fuel to be worth harvesting.

    In making a transgenic organism, what is typically the role of the bacterium?

    Which statement is FALSE regarding the landmark environmental laws passed in the 1960s and 1970s?

How is oil extracted from Canadian tar sands?

What is the definition of “unconventional oil reserves”?

   Which statement is TRUE regarding the greenhouse effect?