I feel I must respond to Cath Basilio's somewhat hysterical letter (aj 25.2.99).
Sixty-six million years ago, give or take a few years, a large meteor, possibly an asteroid, struck the Earth. A prodigious amount of kinetic energy was released and, as a result, the planet's ecosphere was irrecoverably altered. Prior to this, one genus had dominated the Earth for nearly 200,000,000 years, the dinosaurs. Almost overnight, geologically speaking, these groups of archosaurian reptiles were extinct, unable to cope with the sudden changes. However, evolution is an ideal mechanism for dealing with such problems and 65,500,000 years later, homo sapiens evolved.
My point is this: not only was the planet not destroyed by this release of energy, but the climatic changes so triggered led directly to our current being.
As to whose planet it is, the concept of right is purely human. As the current dominant species it is the 'right' of the most powerful factions of the species to decide what can and can't be done with this Earth. Like it or not.