1. Native tribes - Matriarchal/spirit worshippers - mtDNA M
2. Iranians - Asura worshippers
3. Dravidians - horse mounted warrior worshippers
1. Native tribes:
Most of the anthropologists do not believe that matriarchy ever existed and vote only for matriliny. In my opinion, Tulu tribes might have had a matriarchal society initially even as they made the transition to non-tribal* way of life.
The Pandya connection:
Present day Malayalis consider Chera kingdom as native to the region. I just think that is Tamil imperialism. Also, Tulu speaking region never had any connection with Chera kingdom. Since I believe Tulu and Malayali speaking communities came from the common cultural root I have been hoping for a kingdom that has been part of both of these community legends.
The other day, I came across a passage from Megasthenes' Indika.
But those who live near the sea have no kings.. The Pandaean nation is governed by females, and their first queen is said to have been the daughter of Hercules.
Let's forget all those Greek fantastic legends. I think that Pandya region could have been Kerala. The legend of maMgaLe after whom the city of Mangalore is believed to be named also consists few curious facts. Mangale was said to be the queen from Kerala, the region that was governed by females**.
The Tulu region also has an interesting connection to Pandya and matrilineal tradition. According to the legend of Bhutala Pandya, he (Bhutala Pandya or Jaya Pandya) inherited the kingdom from his maternal uncle Deva Pandya and established matrilineal tradition in the whole kingdom.
The manuscript that contains this legend appeared suddenly in 19th century in Tulu region. As of now, legal experts consider it a forgery/hoax with some ulterior motives(the manuscript also describes the matrilineal inheritance rules and caste rules and initially made the basis for matrilineal judicial laws during British rule). The legend also dates the period of this event around 77 CE. However, kings/chieftains with surname Pandya appeared only in 13-14 century in Tulu region.
Whatever be the authenticity of the manuscript, I find it is interesting that matrilineal tradition is associated with kings named Pandya. There were only few kings with that family name. Why the legend didn't make use of more well known and the longest ruling family like Alupa? Of course, Pandya-s who later ruled Tamil region were patriarchal. There could have been cultural changes by that time.
In my opinion, the region of Tulu and Malayalam were initially matriarchal. When the power passed from females to males the children of the ruling matriarchal houses inherited the throne. The transition from female inheritance to male inheritance of the throne was probably brought about patriarchal interlude in these two regions.
In the case of Tulu region, Kadamba period and in the case of Malayali region Ay, Ezhimalai and Chera period are those interludes. After the downfall of these kingdoms the local chieftainship passed to sons of erstwhile ruling matriarch families. The complete patriarchization was probably prevented as the families in this region did not incorporate marriage rules of patriarchal communities. By this time the native tribes might have been overwhelmed by Dravidian speakers( I believe initially patriarchal) who took up the native tradition and also assimilated Iranians speakers.
I believe there could have been some migration by Iranian speakers because of the legend of Asura king Bali. He is revered by both Tulu and Malayali communities. Please check Ravi Mundkur's posts at Tulu Research. They might have migrated along with Dravidian speakers.
In my opinion, Dravidians were originally a pastoral community and worshipped the deity who protected them. A horse mounted deity is very common to lower classes in South India. Even though nowadays the deity is worshipped as an incarnation of Shiva or Vishnu etc... the old depiction is that of a warrior astride the horse. The deity is known by various names.
Maharashtra (herders) -> Khandoba
Andhra Pradesh (herders)-> Mallanna
Karnataka (herders) -> Mailara
Karnataka (Hallaki tribe) -> Bommayya
Karnataka (Tulu region) -> Bermer
Tamil Nadu -> Ayyanar
Kerala -> Sastha
I have not come across any source where it is mentioned that Mallanna in Andhra Pradesh or Mailara in Karnataka is a warrior mounted on the horse. But Khandoba, a pastoral horse mounted deity, has been equated with these two deities.
Probably, the original name of the deity could have been close to Bomm* or Berm* (-ayya and -er are honorifics in Kannada and Tulu respectively) as the Dravidian tribes supposedly inhabited the region close to Semitic tribes. I have already speculated about Abraham and Bermer.
* The tribal matriliny/matriarchy isn't a solid societal structure.
** The female rule phenomenon could be found in epic Mahabharata. However, the region itself had only females. That probably is some kind of fantasy. But in the case of Megasthenes' Pandya-s, he mentioned that kingdom had men and females bore children by the age of six!