The early Arya-s imagined the tumulus (kurgan) as a shelter with the “mother” - i.e. earth. This is clarified in the tR^icha deployed for the funerary rite of the piling of the kurgan, i.e. shmashAna+++(5)+++:
May the earth stand piled high above him; verily upheld by a 1000 props. May it be the house dripping with ghee; Through eternity may he be sheltered here!
Truly that shelter on the steppe has been a great mechanism to understand our pitaraH.
Indeed, I prop up the earth above you… The pitaraH hold up this pillar.
It is clear from the old tradition that there were agni-dagdha and anagnidagdha among the ancestors. While the later were those who were interred, it is clear that both amon the Arya-s and yavana-s some were interred in kurgans after their cremation.
The Dholavira tumulus is incredibly striking. I’ve wondered if it implies some early IE presence among the Harappans. But there is also the dating issue…
The other one, is Mohenjodaro, where archaeologists fear to tread. Because the Buddhist superstructure is on top of the IVC one , the 100CE top would have to be demolished before going lower.