As Calvin tells Hobbes (and I paraphrase), Who looked at a cow first and said lets squeeze this and drink whatever comes out of it" :-).
So where did it all start?
From what little I researched, the concept of religion budded in the Middle Paleolithic age ( about 60,000 years ago) when the Homo Neanderthals had just started living in tribes and bands and having social connections with each other. They did not want their dead to be forgotten and hence started burying them with grave goods. This, as Philip Lieberman suggests, is considered the earliest detectable forms of religious practice since it may signify a "concern for the dead that transcends daily life”. The different rituals came in to being as a means of strengthening social bonding and group cohesion.
Then came the animal worship, though I was able to find lots of information on what animals were worshiped (funnily the animals that were worshipped were also sacrificed at their own altar) I was not able to find why they felt the necessity to worship them at all. What made them think, if I worship the bear, I will have good hunting season?
The upper Paleolithic and later the Neolithic showed an abundance of female imagery such as Venus figurines, which led some to believe that societies had a female-centered religion and a female-dominated society then. (I like that.. I surely do!!! :-)). It was during this time that humans started believing in polytheism or existence of many gods. (According to Vincent W. Fallio) by this time special rituals and ancestor worship were being used by the elites in the society to solidify control over their societies, by convincing their subjects that they possessed a link to the spirit world that also gave them control over the earthly realm.
This was handed down to the later Neolithic age, Bronze and Iron ages by when the religions , rituals and symbols were further trimmed down and become more specific to the regions. Sun, Moon, water, air and the planets started taking on mythical and religious significance. Great works of art and literature sprang from them until religions as we know them now evolved.
Basically what started as respect for the dead and an opportunity to bond with other members of the species has grown uncontrollably into a mega money making destructive machine that is running around the world amok.
While I have delusions of becoming agnostic when frustrated, my upbringing precludes me from that. Too, I have to say that I love my religion and my Gods, however they came in being. Sigh!! Just not their tendency to exacerbate fanatics and violence.
PS: Did you know that that Eve or the first woman (called Mitochondrial Eve) lived almost 50,000 - 80,000 years before Adam or the first man (called Y-chomosomal Adam). So we can trace back matrilineally much longer than patrilineally.
Note: Mitochondrial Eve is defined as the woman who is the matrilineal most recent common ancestor for all living humans. Passed down from mother to offspring, all mitochondrial DNA (mtDNA) in every living person is directly descended from hers. Mitochondrial Eve is the female counterpart of Y-chromosomal Adam, the patrilineal most recent common ancestor, although they lived thousands of years apart.