There's a classic The Far Side comic where two aliens, cleverly disguised as traffic lights, discuss eliminating the Earth's population slowly, one at a time. The joke, of course, is that things aren't always what they seem.
Apparently, filmmakers Les Drew and Kaj Pindal had a similar idea back in 1966, when they made the animated short called What on Earth! The nine-minute movie is a satirical look at Earth from outer space. Specifically, when Martians arrive on our blue rock, they assume, based on the observable conditions, the automobile is the dominant species. It's a warm and funny little video, especially the part about how getting crushed and heading to the junk yard is an individual's final contribution to society. The Film Board says, "This animated short proposes what many earthlings have long feared – that the automobile has inherited the planet. When life on Earth is portrayed as one long, unending conga-line of cars, a crew of extra-terrestrial visitors understandably assume they are the dominant race. While humans, on the other hand, are merely parasites."
What On Earth! was nominated for an Oscar for Best Animated Short in 1967, but lost to something called The Box. Produced by the National Film Board of Canada, the movie was shown in theaters and on ABC television in the US in the 1960s. Now, it is available for your viewing pleasure simply by clicking below.