Can my dog ride in the back of my pickup truck?

I see it all the time but don't think I would ever do it... I have heard some stories of the dog seeing something he can't do without "Like a Squirrel chase" and make a flying lead at 50MPH...

I don't think there is any laws against this - never checked...

I always see alot of dogs with their heads hanging out of the passenger side window. Usually the driver has head out on his side doing the same thing...

"Pure heaven" google image

Roy Ken