Are earth life forms friendly or antagonistic; supportive, or mostly parasitic?

Life on Mars: The Vikings are coming

Racing against time, Jade and her friends must hide evidence of Life on Mars to stop the probes from Earth finding them

Jade is on her way to meet up with her dad, Elvis, for her sixteen-millionth birthday (tortles live a long time in spite of the harsh conditions on Mars), when she gets side-tracked by a strange object that appears to have fallen from the sky. Elvis’ travelling companion Starkwood, an electrostatic plant, is hearing voices, claiming that “The Vikings Are Coming”, while their football-pitch-sized flying friend Fionix confirms the rumour: the Earth has sent two craft to look for life on Mars.
It then becomes a race against time to hide any evidence of such life before Earth destroys it for good. Can Jade and her friends succeed, with help from a Lung Whale, a liquid horse, some flying cats, the Hellas Angels, the Pyrites and a couple of House Martins from the South of France? Oh, and a quantum tunnelling worm – all while avoiding Zombie Vegetables and trouble with a Gravity Artist and the Physics Police?! A gentle and lightly humorous science fantasy adventure.