In Guns, Germs, and Steel, what is an example of the impact that the arrival of humans had on big animals?Guns, Germs, And Steel by Jared Diamond....

There are many examples given in this chapter of the
impact that humans had on large animals.  In general, Diamond is arguing that people
caused the extinction of large animals when they reached the Americas as well as when
they reached Australia/New Guinea.

As an example, on p. 42
of the paperback edition of the book, Diamond points out that Australia/New Guinea had
"its own suite of diverse big mammals."  It also had a 400 pound flightless bird that
resembled an ostrich and marsupials the size of cows.

As
another example, on p. 46, Diamond gives examples of megafauna that lived in the
Americas before humans came.  Among them were such things as elephants, horses, camels,
and lions.  All of these became extinct soon after humans reached the
Americas.

Diamond argues that humans hunted these animals
to extinction and/or hunted the prey that carnivores relied on, thus driving even less
edible animals to extinction.