why are the earth sun and moon spheres why are earthworms important why are earthquakes important why are earthquakes dangerous why are earthquakes caused why are earthworms so important in nature why are earthquakes so hard to predict why are earthquakes happening why are earthquakes so common in myanmar why are earthquakes so common in japan why are earthquakes common in california why are earthworms important to soil why are earthworms invertebrates why are earthworms called farmer friends why is the sky blue on earth why is the earth round why do earthquakes happen if the earth is round why don't we fall off reasons why the earth is not flat reasons why the earth is round why are humans the dominant species on earth 31 reasons why jesus christ came to earth