The constant, or dependent variable is the variable that does not change in the experiment.
There were of course other factors. While early humans did hunt them a lot due to the profits which they received from it (A lot of food, bones they could use for homes, fur they could use for clothing, etc.), there were also other factors such as less food for them which made them less mobile through different geographical regions, etc. (and therefore more susceptible to being hunted) that had played a part in their extinction.
President Nixon believed that normalizing relations with China would "b) drive a wedge between China and the <span>Soviet Union," which was a Cold War goal. </span><span />
George III refused to read the petition and declared the colonists to be traitors.