The Gaia hypothesis is an ecologicalhypothesisproposing that the biosphereand the physical components of the Earth(atmosphere, cryosphere, hydrosphereand lithosphere) are closely integrated to form a complex interacting systemthat maintains the climaticand biogeochemicalconditions on Earth in a preferred homeostasis. Originally proposed by James Lovelockas the earth feedback hypothesis, it was named the Gaia Hypothesis after the Greek supreme goddessof Earth.The hypothesis is frequently described as viewing the Earth as a single organism. Lovelock and other supporters of the idea now call it Gaia theory, regarding it as a scientific theory and not mere hypothesis, since they believe it has passed predictive tests.