Cars are the dominant life form of Earth. Although Ford had taken great care to blend into Earth society, he had "skimped a bit on his preparatory research," a

Cars are the dominant life form of Earth. Although Ford had taken great care to blend into Earth society, he had "skimped a bit on his preparatory research," and thought that the name "Ford Prefect" would be "nicely inconspicuous." The Ford Prefect was a popular British car manufactured from 1938 to 1961, and Adams later clarified in an interview that Ford "had simply mistaken the dominant life form" of Earth: https://en.wikipedia.org/wiki/Ford_Prefect_(character) https://en.wikipedia.org/wiki/Ford_Prefect_(character)