How does animal domestication affect plant production?these can be found in chapter 4.

There are two major ways in which having domesticated
animals helps farmers produce more crops.

First, having
domesticated animals gives the farmers fertilizer.  The dung from the animals can be
used to fertilize the crops.  When this is done, the crops can grow better and more food
can be produced.

Second, in the days before machines,
animals were really important for being able to farm some types of land.  Animals can
pull plows and that allows farmers to break up and plant soil that could not be planted
if farmers were just using their own muscle power (and things like digging sticks) to
break up the soil.