Leviticus 16:4 He shall put on the holy linen coat, and he shall have the linen breeches upon his flesh, and shall be girded with a linen girdle, and with the linen mitre shall he be attired: these are holy garments; therefore shall he wash his flesh in water, and so put them on.
Baptism evolved from ritual washing. So Mormon claims of finding evidence of 'Baptism' in places like Qumran are just hilarious.
There are only so many things one can do with one's body to create a 'cleansing' ritual, or blessing ritual in a largely natural environment. And only so many ways to bend and hold ones arms. With a bit of digging around I am sure one could illustrate the entire temple endowment using tantric carvings from ancient Indian temples.