What bodies?it's same as finger print reading.just had a look at buddhas marks and predicted.and how someone can predict like that.obviously there has to be an ongoing astrological method ages before.
planets, moons, suns, shadow planets like rahu and kethu etc.
cant speak for bodily marks. but astrology with celestial bodies started with extremely simple observations like patterns in climate.
people in ancient times didnt have calendars we are familiar with today. sky was the calendar for them. constellations and their movement across sky showed a yearly pattern that matched with changes in nature due to seasons and the nature of climate. so just like you can predict it will be cold when your calendar says it's june, they knew it will be rainy when, say, sagitarius is at zenith. their lives depended on that natural calendar called astrology. this thought sparked a revolution in thinking they thought sky has patterns that can predict anyone's life. this is how it started.