The Body Snatchers

Blurb

The Body Snatchers is a 1955 science fiction novel by Jack Finney, originally serialized in Colliers Magazine in 1954, which describes the town of Mill Valley, California, being invaded by seeds that have drifted to Earth from space. The seeds replace sleeping people with perfect physical duplicates grown from plantlike pods, while their human victims turn to dust.
The duplicates live only five years, and they cannot sexually reproduce; consequently, if unstopped, they will quickly turn Earth into a dead planet and move on to the next world. One of the duplicate invaders suggests that this is what all humans do; use up resources, wipe out indigenous populations, and destroy ecosystems in the name of survival.
The novel has been adapted for the screen four times; the first film in 1956, the second in 1978, the third in 1993, and the most recent in 2007. Unlike two of the film adaptations, the novel contains an optimistic ending, with the aliens voluntarily vacating after deciding that they cannot tolerate the type of resistance they see in the main characters.