Why are some Rodents considered pets and others pests?

<p>Are Hamsters, Gerbils, Rats &amp; Mice all related?&nbsp;Why do Rodents eat their&nbsp;own poop?&nbsp;Which is the smartest Rodent? </p><p>For free home activities sign-up at <a href="http://www.WhoSmarted.com" rel="noopener noreferrer" target="_blank">www.WhoSmarted.com</a></p><p><br></p><p>See Privacy Policy at <a href="https://art19.com/privacy" rel="noopener noreferrer" target="_blank">https://art19.com/privacy</a> and California Privacy Notice at <a href="https://art19.com/privacy#do-not-sell-my-info" rel="noopener noreferrer" target="_blank">https://art19.com/privacy#do-not-sell-my-info</a>.</p>